DEPARTMENT OF LICENSING AND REGULATORY AFFAIRS  
DIRECTOR'S OFFICE  
GENERAL INDUSTRY SAFETY AND HEALTH STANDARD  
(By authority conferred on the director of the department of licensing and regulatory  
affairs by sections 16 and 21 of 1974 PA 154, MCL 408.1016 and 408.1021, and  
Executive Reorganization Order Nos. 1996-2, 2003-1, 2008-4, and 2011-4, MCL  
445.2001, 445.2011, 445.2025, and 445.2030)  
PART 5. POWERED PLATFORMS FOR BUILDING MAINTENANCE  
GENERAL PROVISIONS  
R 408.10501 Scope.  
Rule 501. (1) This standard covers powered platform installations permanently  
dedicated to interior or exterior building maintenance of a specific structure or group of  
structures. Building maintenance includes, but is not limited to, such tasks as window  
cleaning, caulking, metal polishing and re-glazing.  
(2) This standard does not apply to suspended scaffolds or swinging scaffolds used  
to service buildings on a temporary basis and covered under General Industry Safety and  
Health Standard Part 2 “Walking-Working Surfaces,” nor to suspended scaffolds used for  
construction work and covered under Construction Safety Standard Part 12 “Scaffolds  
and Scaffold Platforms,” and Construction Safety Standard Part 32 “Aerial Work  
Platforms,” as referenced in R 408.10509.  
(3) Powered and manual mobile elevating platforms and self-propelled vehicle  
mounted elevating and rotating platforms are not included in these rules but are provided  
for in General Industry Safety and Health Standard Part 58 “Aerial Work Platforms,” as  
referenced in R 408.10509.  
(4) Scaffolds are not included in these rules but are provided for in General Industry  
Safety and Health Standard Part 2 “Walking-Working Surfaces,” as referenced in  
R 408.10509.  
History: 1979 AC; 2008 AACS; 2016 AACS; 2018 AACS.  
R 408.10502 Applicability for powered platforms.  
Rule 502. (1) Permanent installations in existence and or completed before July 23,  
1990 shall comply with R 408.10574(2), R 408.10578 to R 408.10582, R 408.10585 to  
R 408.10592 and Appendix C of General Industry Safety and Health Standard Part 33  
“Personal Protective Equipment,” as referenced in R 408.10509.  
(2) These rules apply to all new permanent installations for powered platforms and  
modifications to existing buildings that affect the structural integrity of the building  
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exterior, tie-in guides and attachments, and the supporting structure for the powered  
platforms.  
(3) Employers shall ensure compliance with these rules for any powered platform  
that is powered by a source other than electricity except for those rules that govern the  
electrical power source. The alternative power source shall be outfitted with protective  
devices that are equivalent to the protection that is provided by rules pertaining to an  
electrical power source.  
(4) Permanent installations shall be in compliance with the provisions of Appendix  
D “Existing Installations – Mandatory.”  
(5) The following standards are referenced in Appendix D and adopted in  
R 408.40509.  
(a) ANSI A120.1 "Safety Requirements for Powered Platforms for Exterior Building  
Maintenance” 1970 edition.  
(b) General Industry Safety Standard Part 39 “Design Safety Standards for Electrical  
Systems."  
History: 1979 AC; 1992 AACS; 2008 AACS; 2016 AACS; 2018 AACS.  
R 408.10503 Definitions; A to D.  
Rule 503. (1) "Anemometer" means an instrument for measuring wind velocity.  
(2) "Angulated roping" means a suspension method where the upper point of  
suspension is inboard from the attachments on the suspended unit, thus causing the  
suspended unit to bear against the face of the building.  
(3) "Building face roller" means a rotating cylindrical member that is designed to  
ride on the face of the building wall to prevent the platform from abrading the face of the  
building and to assist in stabilizing the platform.  
(4) “Building maintenance” means operations such as window cleaning, caulking,  
metal polishing, re-glazing, and general maintenance on building surfaces.  
(5) “Cable” means a conductor, or group of conductors, enclosed in a weatherproof  
sheath, that may be used to supply electrical power or control current, or both, for  
equipment or to provide voice communication circuits.  
(6) “Carriage” means a wheeled vehicle used for the horizontal movement and  
support of other equipment.  
(7) “Certification” means a written, signed, and dated statement confirming the  
performance of a requirement of this standard.  
(8) “Combination cable” means a cable having both steel structural members  
capable of supporting the platform, and copper or other electrical conductors insulated  
from each other and the structural members by nonconductive barriers.  
(9) “Competent person” means a person who, because of training and experience, is  
capable of identifying hazardous or dangerous conditions in powered platform  
installations and of training employees to identify such conditions.  
(10) “Continuous pressure” means the need for constant manual actuation for a  
control to function.  
(11) “Control” means a mechanism used to regulate or guide the operation of the  
equipment.  
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(12) "Davit" means a device that is used singly or in pairs and that is for suspending  
a powered platform from work, storage, or rigging locations on the building being  
serviced. Unlike outriggers, a davit reacts its operating load into a single roof socket or  
carriage attachment.  
History: 1979 AC; 1992 AACS; 2018 AACS.  
R 408.10504 Definitions; E to L.  
Rule 504. (1) “Equivalent” means alternative designs, materials, or methods that the  
employer can demonstrate will provide an equal or greater degree of safety for employees  
than the methods, materials, or designs specified in the standard.  
(2) “Ground rigging” means a method of suspending a working platform starting  
from a safe surface to a point of suspension above the safe surface.  
(3) “Ground rigged davit” means a davit that cannot be used to raise a suspended  
working platform above the building face being serviced.  
(4) “Guide button” means a building face anchor designed to engage a guide track  
mounted on a platform.  
(5) “Guide roller” means a rotating cylindrical member, operating separately or as  
part of a guide assembly, designed to provide continuous engagement between the  
platform and the building guides or guideways.  
(6) “Guide shoe” means a device attached to the platform designed to provide a  
sliding contact between the platform and the building guides.  
(7) “Hoisting machine” means a device intended to raise and lower a suspended or  
supported unit.  
(8) “Hoist rated load” means the hoist manufacturer's maximum allowable operating  
load.  
(9) “Installation” means all the equipment and all affected parts of a building that are  
associated with the performance of building maintenance using powered platforms.  
(10) “Interlock” means a device designed to ensure that operations or motions occur  
in proper sequence.  
(11) “Intermittent stabilization” means a method of platform stabilization in which  
the angulated suspension wire rope or ropes are secured to regularly spaced building  
anchors.  
(12) “Lanyard” means a flexible line of rope, wire rope, or strap that is used to  
secure the body belt or body harness to a deceleration device, lifeline, or anchorage.  
(13) “Lifeline” means a component consisting of a flexible line for connection to an  
anchorage at 1 end to hang vertically, vertical lifeline, or for connection to anchorages at  
both ends to stretch horizontally, horizontal lifeline, and which serves as a means for  
connecting other components of a personal fall arrest system to the anchorage.  
(14) “Live load” means the total static weight of workers, tools, parts, and supplies  
that the equipment is designed to support.  
History: 1979 AC; 2018 AACS.  
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R 408.10505 Definitions; M, O.  
Rule 505. (1) "Mobile elevating platform" means a type of freestanding scaffolding  
that can be manually moved horizontally from 1 area to another and raised or lowered  
manually or with power to predetermined heights.  
(2) “Obstruction detector” means a control that will stop the suspended or supported  
unit in the direction of travel if an obstruction is encountered, and will allow the unit to  
move only in a direction away from the obstruction.  
(3) “Operating control” means a mechanism regulating or guiding the operation of  
equipment that ensures a specific operating mode.  
(4) “Operating device” means a device actuated manually to activate a control.  
(5) “Outrigger” means a device, used singly or in pairs, for suspending a working  
platform from work, storage, and rigging locations on the building being serviced. Unlike  
davits, an outrigger reacts its operating moment load as at least 2 opposing vertical  
components acting into 2 or more distinct roof points and or attachments.  
History: 1979 AC; 2018 AACS.  
R 408.10506 Definitions; P, R.  
Rule 506. (1) “Platform rated load” means the combined weight of workers, tools,  
equipment, and other material which is permitted to be carried by the working platform at  
the installation, as stated on the load rating plate.  
(2) “Poured socket” means the method of providing wire rope terminations in which  
the ends of the rope are held in a tapered socket by means of poured spelter or resins.  
(3) "Powered platform" means scaffolding equipment that consists of a permanently  
installed, power-operated working platform and a roof car or other suspension means.  
(4) “Primary brake” means a brake designed to be applied automatically whenever  
power to the prime mover is interrupted or discontinued.  
(5) “Prime mover” means the source of mechanical power for a machine.  
(6) “Rated load” means the manufacturer's recommended maximum load.  
(7) “Rated strength” means the strength of wire rope, as designated by its  
manufacturer or vendor, based on standard testing procedures or acceptable engineering  
design practices.  
(8) “Rated working load” means the combined static weight of persons, materials,  
and suspended or supported equipment.  
(9) "Registered professional engineer" means a person who has been duly and  
currently registered and who is licensed by an authority within the United States or its  
territories to practice the profession of engineering.  
(10) "Roof car" means a structure that is for suspending a working platform and that  
provides for the platform's horizontal movement to work positions.  
(11) “Roof powered platform” means a working platform where the hoist or hoists  
used to raise or lower the platform is located on the roof.  
(12) “Roof rigged davit” means a davit used to raise the suspended working  
platform above the building face being serviced. This type of davit can also be used to  
raise a suspended working platform that has been ground-rigged.  
(13) “Rope” means the equipment used to suspend a component of an equipment  
installation, such as wire rope.  
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History: 1979 AC; 1992 AACS; 2018 AACS.  
R 408.10507 Definitions; S.  
Rule 507. (1) “Safe surface” means a horizontal surface intended to be occupied by  
personnel, which is so protected by a fall protection system that it can be reasonably  
assured that said occupants will be protected against falls.  
(2) "Safety factor" means a ratio of the breaking strength of a piece of material or  
object to the maximum designed load or stress that is applied when in use.  
(3) "Scaffold" means an elevated work platform that is for supporting both  
employees and materials and that is temporary in nature.  
(4) “Secondary brake” means a brake designed to arrest the descent of the suspended  
or supported equipment in the event of an overspeed condition.  
(5) “Self-powered platform” means a working platform where the hoist or hoists  
used to raise or lower the platform is mounted on the platform.  
(6) “Speed reducer” means a positive type speed reducing machine.  
(7) “Stability factor” means the ratio of the stabilizing moment to the overturning  
moment.  
(8) “Stabilizer tie” means a flexible line connecting the building anchor and the  
suspension wire rope supporting the platform.  
(9) “Supported equipment” means building maintenance equipment that is held or  
moved to its working position by means of attachment directly to the building or  
extensions of the building being maintained.  
(10) “Suspended equipment” means building maintenance equipment that is  
suspended and raised or lowered to its working position by means of ropes or  
combination cables attached to some anchorage above the equipment.  
(11) “Suspended scaffold”, also known as swinging scaffold, means a scaffold  
supported on wire or other ropes, used for work on, or for providing access to, vertical  
sides of structures on a temporary basis. Such scaffold is not designed for use on a  
specific structure or group of structures.  
History: 1979 AC; 1992 AACS; 2018 AACS.  
R 408.10508 Definitions; T to W.  
Rule 508. (1) “Tail line” means the non-supporting end of the wire rope used to  
suspend the platform.  
(2) "Tie-in guides" means the portion of a building that provides continuous positive  
engagement between the building and a suspended or supported unit during its vertical  
travel on the face of the building.  
(3) “Traction hoist” means a type of hoisting machine that does not accumulate the  
suspension wire rope on the hoisting drum or sheave, and is designed to raise and lower a  
suspended load by the application of friction forces between the suspension wire rope and  
the drum or sheave.  
(4) “Transportable outriggers” means outriggers designed to be moved from 1 work  
location to another.  
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(5) “Trolley carriage” means a carriage suspended from an overhead track structure.  
(6) “Verified” means accepted by design, evaluation, or inspection by a registered  
professional engineer.  
(7) “Weatherproof” means so constructed that exposure to adverse weather  
conditions will not affect or interfere with the proper use or functions of the equipment or  
component.  
(8) “Winding drum hoist” means a type of hoisting machine that accumulates the  
suspension wire rope on the hoisting drum.  
(9) "Working platform" means suspended or supported equipment intended to  
provide access to the face of a building and manned by persons engaged in building  
maintenance.  
(10) “Wrap” means 1 complete turn of the suspension wire rope around the surface  
of a hoist drum.  
History: 1979 AC; 1992 AACS; 2018 AACS.  
R 408.10509 Adopted and referenced standards.  
Rule 509. (1) The following standard, American National Society Institute (ANSI)  
Standard ANSI A120.1 ‘Safety Requirement for Powered Platforms for Exterior Building  
Maintenance,’ 1970 edition, also known as American Society of Mechanical Engineers  
(ASME) Standard ASME A120.1 ‘Safety Requirements Powered Platforms and  
Traveling Ladders and Gantries for Building Maintenance,’ 1970 edition is adopted by  
reference in these rules and is available from IHS Global, 15 Inverness Way East,  
Englewood, Colorado, 80112, USA, telephone number: 1-800-854-7179 or via the  
internet at website: www.global.ihs.com, at a cost at the time of adoption of these rules of  
$20.00.  
(2) The standard adopted in these rules is available for inspection at the Department  
of Licensing and Regulatory Affairs, MIOSHA Regulatory Services Section, 530 West  
Allegan Street, P.O. Box 30643, Lansing, Michigan, 48909-8143.  
(3) The standard adopted in these rules may be obtained from the publisher or may  
be obtained from the Department of Licensing and Regulatory Affairs, MIOSHA  
Regulatory Services Section, 530 West Allegan Street, P.O. Box 30643, Lansing,  
Michigan, 48909-8143, at the cost charged in this rule, plus $20.00 for shipping and  
handling.  
(4) The following Michigan Occupational Safety and Health Administration  
(MIOSHA) standards are referenced in these rules. Up to 5 copies of these standards may  
be obtained at no charge from the Michigan Department of Licensing and Regulatory  
Affairs, MIOSHA Regulatory Services Section, 530 West Allegan Street, P.O. Box  
30643, Lansing, Michigan, 48909-8143 or via the internet at website:  
www.michigan.gov/mioshastandards. For quantities greater than 5, the cost, at the time of  
adoption of these rules, is 4 cents per page.  
(a) General Industry Safety and Health Standard Part 2 “Walking-Working  
Surfaces,” R 408.10201 to R 408.10241.  
(b) General Industry Safety Standard Part 7 “Guards for Power Transmission,”  
R 408.10701 to R 408.10765.  
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(c) General Industry Safety Standard Part 8 “Portable Fire Extinguishers,”  
R 408.10801 to R 408.10839.  
(d) General Industry Safety and Health Standard Part 33 “Personal Protective  
Equipment,” R 408.13301 to R 408.13398.  
(e) General Industry Safety Standard Part 39 “Design Safety Standards for Electrical  
Systems,” R 408.13901 to R 408.13902.  
(f) General Industry Safety and Health Standard Part 58 “Aerial Work Platforms,”  
R 408.15801 to R 408.15842.  
(g) Construction Safety Standard Part 12 “Scaffolds and Scaffold Platforms,”  
R 408.41201 to R 408.41264.  
(h) Construction Safety Standard Part 32 “Aerial Work Platforms,” R 408.43201 to  
R 408.43220.  
History: 2008 AACS; 2013 AACS; 2016 AACS; 2018 AACS.  
R 408.10511 Rescinded.  
History: 1979 AC; 1983 AACS; 2008 AACS; 2016 AACS; 2018 AACS.  
R 408.10512 Rescinded.  
History: 1979 AC; 1981 AACS; 2016 AACS; 2018 AACS.  
R 408.10513 Rescinded.  
History: 1979 AC; 1981 AACS; 1983 AACS; 2008 AACS; 2016 AACS; 2018 AACS.  
R 408.10518 Assurance.  
Rule 518. Building owners of all installations, new and existing, shall inform the  
employer in writing that the installation has been inspected, tested, and maintained in  
compliance with the requirements of R 408.10574(2), R 408.10578 to R 408.10582, and  
R 408.10585 to R 408.10589, and that all anchorages meet the requirements of  
R 408.13395a(14) of General Industry Safety and Health Standard Part 33 “Personal  
Protective Equipment" as referenced in R 408.10509.  
History: 2018 AACS.  
R 408.10521 Rescinded.  
History: 1979 AC; 1981 AACS; 2016 AACS; 2018 AACS.  
R 408.10522 Rescinded.  
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History: 1979 AC; 2016 AACS; 2018 AACS.  
R 408.10523 Rescinded.  
History: 1979 AC; 2016 AACS; 2018 AACS.  
R 408.10524 Rescinded.  
History: 1979 AC; 1981 AACS; 2016 AACS; 2018 AACS.  
R 408.10525 Rescinded.  
History: 1979 AC; 1981 AACS; 1983 AACS; 2016 AACS; 2018 AACS.  
R 408.10526 Rescinded.  
History: 1979 AC; 2008 AACS; 2016 AACS; 2018 AACS.  
R 408.10527 Rescinded.  
History: 1979 AC; 1981 AACS; 2018 AACS.  
R 408.10528 Rescinded.  
History: 1979 AC; 2008 AACS; 2016 AACS; 2018 AACS.  
R 408.10529 Rescinded.  
History: 1979 AC; 1983 AACS; 2016 AACS; 2018 AACS.  
R 408.10530 Rescinded.  
History: 1979 AC; 2018 AACS.  
R 408.10531 Rescinded.  
History: 1979 AC; 2018 AACS.  
R 408.10532 Rescinded.  
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History: 1979 AC; 1983 AACS; 2008 AACS; 2016 AACS; 2018 AACS.  
R 408.10533 Rescinded.  
History: 1979 AC; 2018 AACS.  
R 408.10534 Rescinded.  
History: 1979 AC; 2018 AACS.  
R 408.10535 Rescinded.  
History: 1979 AC; 1983 AACS; 2018 AACS.  
R 408.10541 Rescinded.  
History: 1979 AC; 2013 AACS; 2018 AACS.  
R 408.10542 Rescinded.  
History: 1979 AC; 1981 AACS; 2016 AACS; 2018 AACS.  
R 408.10543 Rescinded.  
History: 1979 AC; 2018 AACS.  
R 408.10544 Rescinded.  
History: 1979 AC; 2016 AACS; 2018 AACS.  
R 408.10545 Rescinded.  
History: 1979 AC; 2018 AACS.  
R 408.10546 Rescinded.  
History: 1979 AC; 2008 AACS; 2016 AACS; 2018 AACS.  
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R 408.10547 Rescinded.  
History: 2008 AACS; 2016 AACS.  
R 408.10548 Rescinded.  
History: 1979 AC; 2016 AACS; 2018 AACS.  
R 408.10549 Rescinded.  
History: 1979 AC; 2018 AACS.  
R 408.10550 Rescinded.  
History: 1979 AC; 2018 AACS.  
R 408.10561 Installations.  
Rule 561. (1) A powered platform installed, or that part of a powered platform  
modified, after August 27, 1971, shall be in compliance with the design and  
manufacturing requirements prescribed in ANSI A120.1, “Safety Requirements for  
Powered Platforms for Exterior Building Maintenance,” 1970 edition, as adopted in  
R 408.10509, and as further prescribed in the rules of this standard.  
(2) The following requirements apply to affected parts of buildings that utilize  
working platforms for building maintenance:  
(a) Structural supports, tie-downs, tie-in guides, anchoring devices, and any affected  
parts of the building that are included in the installation shall be designed by, or under the  
direction of, a registered professional engineer who is experienced in such design.  
(b) Exterior installations shall be capable of withstanding prevailing climatic  
conditions.  
(c) The building installation shall provide safe access to, and egress from, the  
equipment and shall provide sufficient space to conduct necessary maintenance of the  
equipment.  
(d) The affected parts of the building shall have the capability of sustaining all of the  
loads imposed by the equipment.  
(e) The affected parts of the building shall be designed to allow the equipment to be  
used without exposing employees to a hazardous condition.  
(3) The exterior of each building shall be provided with tie-in guides unless the  
conditions specified in either of the following provisions are met:  
(a) Tie-in guides required pursuant to this rule may be eliminated for not more than  
75 feet (22.9 m) of the uppermost elevation of the building if angulated roping is  
employed, if the use of tie-in guides is not feasible due to the exterior building design,  
and if an angulation force of not less than 10 pounds (44.4 n) is maintained under all  
conditions of loading.  
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(b) Tie-in guides may be eliminated if 1 of the specified guide systems is provided  
as specified in R 408.10562 and R 408.10563.  
History: 1979 AC; 1981 AACS; 1983 AACS; 1992 AACS; 2008 AACS; 2016 AACS.  
R 408.10562 Intermittent stabilization systems.  
Rule 562. (1) An intermittent stabilization system shall keep equipment in  
continuous contact with the building facade and shall prevent sudden horizontal  
movement of the platform. The system may be used together with continuous positive  
building guide systems that use tie-in guides on the same building if the requirements  
for each system are met.  
(2) The maximum vertical interval between building anchors shall be 3 floors or  
50 feet (15.3 m), whichever is less.  
(3) Building anchors shall be located vertically so that attachments  
of the  
stabilizer ties will not cause the platform suspension ropes to angulate the platform  
horizontally across the face of the building. The anchors shall be positioned  
horizontally on the building face so as to be symmetrical about the platform suspension  
ropes.  
(4) Building anchors shall be visible to employees and shall allow a stabilizer tie  
attachment for each of the platform suspension ropes at each vertical interval. If  
more than 2 suspension ropes are used on a platform, only the 2 building-side  
suspension ropes at the platform ends shall require a stabilizer attachment.  
(5) Building anchors that extend beyond the face of the building shall be free of  
sharp edges or points. Where cables, suspension wire ropes, and lifelines may be in  
contact with the building face, external building anchors shall not interfere with their  
handling or operation.  
(6) The intermittent stabilization system building anchors and components  
shall be capable of sustaining, without failure, not less than 4 times the maximum  
anticipated load applied or transmitted to the components and anchors. If 2  
anchors share the wind load, the minimum design wind load for each anchor shall be  
300 pounds (1334 n).  
(7) The building anchors and stabilizer ties shall be capable of sustaining  
anticipated horizontal and vertical loads from winds specified for roof storage design  
which may act on the platform and wire ropes if the platform is stranded on a building  
face. If the building anchors have different spacing than the suspension wire rope or  
if the building requires different suspension spacings on 1 platform,  
anchor and stabilizer tie shall be capable of sustaining the wind loads.  
1
building  
(8) A powered platform shall be suspended by 2 or more cables. Where 2 cables  
are used, each employee on the work platform shall use a safety harness and lanyard  
that is attached to an individual lifeline. The lifeline shall be secured to the  
building structure and shall be independent of any cable and structures that support  
the powered platform.  
(9) When normal voice communication cannot be understood,  
a
powered  
platform shall be equipped with a 2-way voice communication system between the  
operator and persons who are stationed at a supervised location in the vicinity or within  
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the building being serviced. The communication system shall be operative and shall be  
tended at all times.  
(10) Where thrustouts are used in place of a roof car, they shall be anchored to  
the building structure with fasteners that are capable of sustaining the imposed load.  
History: 1979 AC; 1992 AACS.  
R 408.10563 Button guide stabilization systems.  
Rule 563. (1) Guide buttons shall be coordinated  
equipment.  
with  
platform-mounted  
(2) Guide buttons shall be located horizontally on the building face to allow  
engagement of each of the guide tracks mounted on the platform.  
(3) Guide buttons shall be located in vertical rows on the building face for proper  
engagement of the guide tracks mounted on the platform.  
(4) Two guide buttons shall engage each guide track at all times, except for the  
initial engagement.  
(5) Guide buttons that extend beyond the face of the building shall be free of  
sharp edges or points. Where cables, ropes, and lifelines may be in contact with the  
building face, guide buttons shall not interfere with their handling or operation.  
(6) Guide buttons, connections, and seals shall be capable of sustaining,  
without damage, at least the weight of the platform or the guide tracks or guide track  
connectors shall have provisions to prevent the platform and its attachments from  
transmitting the weight of the platform to the guide buttons, connections, and seals.  
In either case, the minimum design load shall be 300 pounds (1334 n) per building  
anchor.  
History: 1979 AC; 1992 AACS.  
R 408.10564 Design of installation; equipment.  
Rule 564. (1) The requirements of this rule apply to equipment that is part of a  
powered platform installation, such as any of the following:  
(a) Platforms.  
(b) Stabilizing components.  
(c) Carriages.  
(d) Outriggers.  
(e) Hoisting machines.  
(f) Wire ropes.  
(g) Electrical components.  
(2) Equipment installations shall be designed by, or under the direction of, a  
registered professional engineer who is experienced in such design.  
(3) The design shall provide for a minimum live load of 250 pounds (113.6 kg) for  
each occupant of a suspended or supported platform.  
(4) Equipment that is exposed to wind when not in service shall be designed to  
withstand forces generated by winds that have a velocity of at least 100 miles per hour  
(44.7 m/s) at 30 feet (9.2 m) above grade.  
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(5) Equipment that is exposed to wind when in service shall be designed to  
withstand forces generated by winds that have a velocity of at least 50 miles per hour  
(22.4 m/s) for all elevations.  
(6) Bolted connections shall be self-locking or shall otherwise be secured to prevent  
the loss of the connections by vibration.  
History: 1979 AC; 1992 AACS; 2016 AACS.  
R 408.10565 Roof cars; carriages; suspension methods.  
Rule 565. (1) A roof car shall be used when it is necessary to move a working  
platform horizontally to a work or storage position.  
(2) Movements of a roof car shall be restricted to a designated path of travel.  
Mechanical stops shall be provided and shall prevent the roof car from traversing outside  
the intended path of travel. The stops shall be capable of withstanding a force equal to  
100% of the inertial effect of the roof car under power and shall be designed to prevent a  
crushing or shearing hazard.  
(3) Elevated building maintenance equipment shall be suspended by a roof car,  
carriage, outrigger, davits, or an equivalent method.  
(4) Carriages or roof cars shall be in compliance with all of the following provisions:  
(a) The horizontal movement of a carriage shall be controlled to ensure its safe  
movement and allow accurate positioning of the platform for vertical travel or storage.  
(b) Powered carriages shall not exceed a traversing speed of 50 feet per minute (0.3  
ms).  
(c) The initiation of a traversing movement for a manually propelled carriage on a  
smooth level surface shall not require a person to exert a horizontal force of more than 40  
pounds (444.8 n).  
(d) Structural stops and curbs shall be provided to prevent the traversing of the  
carriage beyond its designed limits of travel.  
(e) Traversing controls for a powered carriage shall be of a continuous pressure  
weatherproof type. Multiple controls, when provided, shall be arranged to permit  
operation from only 1 control station at a time. An emergency stop device shall be  
provided on each end of a powered carriage for interrupting power to the carriage drive  
motors.  
(f) The operating control or controls shall be connected so that, in the case of  
suspended equipment, traversing of a carriage is not possible until the suspended portion  
of the equipment is located at its uppermost designed position for traversing and is free of  
contact with the face of the building or building guides. All protective devices and  
interlocks shall be in the proper position to allow traversing of the carriage.  
(g) Stability for underfoot supported carriages shall be obtained by gravity, by an  
attachment to a structural support, or by a combination of gravity and a structural support.  
The use of flowing counterweights to achieve stability is prohibited.  
(h) The stability factor against overturning shall not be less than 5 for horizontal  
traversing of the carriage, including the effects of impact and wind.  
(i) The carriages and their anchorages shall be capable of resisting accidental  
over-tensioning of the wire ropes that suspend the working platform, and this calculated  
value shall include the effect of 1-1/2 times the stall capacity of the hoist motor. The  
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forces that result from the stall load of the hoist and 1/2 of the wind load shall not cause  
damage to any part of the installation.  
(j) Roof carriages that rely on having tie-down devices secured to the building to  
develop the required stability against overturning shall be provided with an interlock that  
will prevent vertical platform movement unless the tie-down is engaged.  
(k) An automatically applied braking or locking system, or an equivalent, shall be  
provided that will prevent the unintentional traversing of power-traversed or  
power-assisted carriages.  
(l) A manual or automatic braking or locking system, or an equivalent, shall be  
provided that will prevent the unintentional traversing of manually propelled carriages.  
(m) A means to lock out the power supply for the carriage shall be provided.  
(n) Safe access to, and egress from, the carriage shall be provided from a safe  
surface. If the carriage traverses an elevated area, any operating area on the carriage shall  
be protected by a guardrail system in compliance with General Industry Safety and  
Health Standard Part 2 “Walking-Working Surfaces,” as referenced in R 408.10509. Any  
access gate shall be self-closing and self-latching or shall be provided with an interlock.  
(o) Each carriage work station position shall be identified by location markings or  
position indicators, or both.  
(p) A motor shall stall if the load on the hoist motor is at any time more than 3 times  
that necessary for lifting the working platform with its rated load.  
History: 1979 AC; 1992 AACS; 2008 AACS; 2016 AACS; 2018 AACS.  
R 408.10566 Outriggers.  
Rule 566. (1) Outriggers may be used as a method of suspension for ground-  
rigged working platforms where the point of suspension is not more than 300 feet (91.5  
m) above a safe surface. A tie-in guide system or systems shall be provided and shall  
be in compliance with the requirements of R 408.10561 and R 408.10562.  
(2) Outriggers shall be used only with self-powered, ground-rigged working  
platforms.  
(3) Each outrigger shall be secured with a tie-down to a verified anchorage on  
the building during the entire period of its use. The anchorage shall be designed to  
have a stability factor of not less than 4 against overturning or upsetting the outrigger.  
(4) Access to and egress from the working platform shall be from and to a safe  
surface below the point of suspension.  
(5) Each portable outrigger shall be designed for lateral stability to prevent  
rollover if lateral load is accidentally applied to the outrigger.  
The accidental lateral load to be considered in this design system shall be not less  
than 70% of the rated load of the hoist.  
(6) Each portable outrigger shall be designed to support a load of not less than 4  
times the rated load of the hoist.  
(7) Each portable outrigger shall be located so that the suspension wire ropes for  
2-point suspended working platforms are hung parallel.  
(8) A portable outrigger shall be tied back to a verified anchor on the building  
with a rope that is equivalent in strength to the suspension rope.  
(9) The tie-back rope shall be installed parallel to the centerline of the outrigger.  
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History: 1979 AC; 1981 AACS; 1992 AACS.  
R 408.10567 Davits.  
Rule 567. (1) Every davit installation, whether fixed or portable or rotatable or  
non-rotatable, shall be designed and installed to ensure that it has a stability factor against  
overturning of not less than 4.  
(2) Both of the following requirements apply to roof-rigged davit systems:  
(a) Access to and egress from the working platform shall be from a safe surface.  
Access or egress shall not require a person to climb over a building's parapet or guard  
railing.  
(b) The working platform shall be provided with wheels, casters, or a carriage for  
traversing horizontally.  
(3) Both of the following requirements apply to ground-rigged davit systems:  
(a) The point of suspension shall not be more than 300 feet (91.5 m) above a safe  
surface. A guide system or systems shall be provided and shall be in compliance with the  
requirements of R 408.10561 and R 408.10562.  
(b) Access and egress to and from the working platform shall only be from a safe  
surface that is below the point of suspension.  
(4) A rotating davit shall not require a horizontal force of more than 40 pounds  
(177.9 n) per person to initiate a rotating movement.  
(5) All of the following requirements apply to portable davits:  
(a) A davit or part of a davit that weighs more than 80 pounds (36 kg) shall be  
provided with a means for its transport, which shall keep the center of gravity of the davit  
at or below 36 inches (914 mm) above the safe surface during transport.  
(b) A davit shall be provided with a pivoting socket or with a base that will allow the  
insertion or removal of a davit at a position of not more than 35 degrees above the  
horizontal, with the complete davit inboard of the building face being serviced.  
(c) Means shall be provided to lock the davit to its socket or base before it is used to  
suspend the platform.  
History: 1979 AC; 1992 AACS; 2016 AACS.  
R 408.10568 Roof guarding.  
Rule 568. (1) Employees who work on roofs while performing building maintenance  
shall be protected by a perimeter guarding system that meets the requirements of General  
Industry Safety and Health Standard Part 2 “Walking-Working Surfaces,” as referenced  
in R 408.10509.  
(2) The perimeter guard shall not be more than 6 inches (152 mm) inboard of the  
inside face of a barrier, for example, the parapet wall, or roof edge curb of the building  
being serviced; however, the perimeter guard location shall not be set back more than 18  
inches (457 mm) from the exterior building face.  
History: 1992 AACS; 2008 AACS; 2016 AACS; 2018 AACS.  
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R 408.10568a Equipment stops.  
Rule 568a. Operational areas for trackless type equipment shall be provided with  
structural stops, such as curbs, to prevent equipment from traveling outside its intended  
travel areas and to prevent a crushing or shearing hazard.  
History: 2016 AACS.  
R 408.10568b Maintenance access.  
Rule 568b. Means shall be provided to traverse all carriages and their suspended  
equipment to a safe area for maintenance and storage. Maintenance shall be performed  
on equipment in a stored position when possible.  
History: 2016 AACS.  
R 408.10568c Elevated track.  
Rule 568c. Either of the following must be provided:  
(a) An elevated track system that is located 4 feet (1.2 m) or more above a safe  
surface and that is traversed by carriage supported equipment shall be provided with a  
walkway and guardrail system.  
(b) The working platform that is capable of being lowered, as part of its normal  
operation, to the lower safe surface for access and egress of the personnel and provided  
with a safe means of access and egress to the lower safe surface.  
History: 2016 AACS.  
R 408.10568d Tie-down anchors.  
Rule 568d. Imbedded tie-down anchors, fasteners, and affected structures shall be  
resistant to corrosion.  
History: 2016 AACS.  
R 408.10568e Cable stabilization.  
Rule 568e. (1) Hanging lifelines and all cables that are not in tension shall be  
stabilized at 200-foot (61 m) intervals of vertical travel of the working platform beyond  
an initial 200-foot (61 m) distance.  
(2) Hanging cables, other than suspended wire ropes, that are in constant tension  
shall be stabilized when the vertical travel is more than an initial 600-foot (183 m)  
distance. Beyond the initial 600 feet, cables shall be stabilized at intervals of 600 feet  
(183 m) or less.  
History: 2016 AACS.  
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R 408.10568f Emergency planning.  
Rule 568f. An employer shall develop and implement a written emergency action  
plan for each kind of working platform operation. This plan shall explain the emergency  
procedures that are to be followed in the event of a power failure, equipment failure, or  
other emergencies which may be encountered. The plan shall include building  
emergency escape routes, procedures, and alarm systems to be used by each employee  
before operating a platform. Upon initial assignment and when the plan is changed, the  
employer shall review, with each employee, those parts of the plan that the employee is  
required to know in the event of an emergency.  
History: 2016 AACS.  
R 408.10568g Building maintenance.  
Rule 568g. Repairs or major maintenance of those building portions that provide  
primary support for the suspended equipment shall not affect the capability of the  
building to be in compliance with the requirements of these rules.  
History: 2016 AACS.  
R 408.10569 Electrical requirements.  
Rule 569. The following electrical requirements apply to buildings that utilize  
working platforms for building maintenance:  
(a) General building electrical installations shall be in compliance with the  
provisions of General Industry Safety Standard Part 39 “Design Safety Standards for  
Electrical Systems," as referenced in R 408.10509.  
(b) Building electrical wiring shall be of such capacity that when a full load is  
applied to the equipment power circuit not more than a 5% drop from building  
service-vault voltage will occur at any power circuit outlet that is used by equipment  
regulated by these rules.  
(c) The equipment power circuit shall be an independent electrical circuit that  
remains separate from all other equipment within or on the building, other than power  
circuits that are used for hand tools which will be used in conjunction with the  
equipment. If the building has an emergency power system, the equipment power circuit  
may also be connected to this system.  
(d) The power circuit shall be provided with a disconnect switch that can be locked  
in the "off" or "on" position. The switch shall be located to allow the operators of the  
equipment access to the switch.  
(e) The disconnect switch for the power circuit shall be locked in the "on" position  
when the equipment is in use.  
History: 1992 AACS; 2008 AACS; 2016 AACS.  
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R 408.10570. Controls and interlocks.  
Rule 570. Where a roof car is used, safety interlocks shall be provided to ensure that the  
working platform will not leave the stored position until the required positive position  
anchor is engaged and to ensure that the roof car cannot move when the working platform  
is not in the stored position.  
History: 1992 AACS; 2013 AACS.  
R 408.10571 Safety factors.  
Rule 571. All of the parts of a powered platform that are subject to stress, except  
for the wire rope, shall have a design safety factor of not less than 5. Wire rope shall  
have a design safety factor of not less than 10.  
History: 1979 AC; 1992 AACS.  
R 408.10572 Working platforms.  
Rule 572. A working platform that is used on the exterior of a building shall be  
equipped with rollers which will be in contact with the building face. Where the vertical  
working travel of a working platform is more than 130 feet, the platform shall be  
equipped with guide rollers or guide shoes which shall positively engage guides, such as  
"t" rails or indented mullions. The guide rollers or guide shoes shall enter the guides at  
the lowest possible speed and shall not require any manual assistance from an employee  
while the work platform is in motion. A working platform that is installed before the  
effective date of this standard and that has a rise of more than 130 feet may use an  
equivalent means to tie the platform to the building instead of guide rollers or guide  
shoes.  
History: 1979 AC; 1992 AACS; 2016 AACS.  
R 408.10573 Inspections and tests.  
Rule 573. (1) An employer that has a powered platform under the employer's control  
shall do all of the following:  
(a) Provide operating instructions and a checklist for a visual inspection which shall  
be used by the operator before each daily use of the platform. The visual inspection shall  
include a check of the platform controls and safety interlocks.  
(b) Provide for a physical inspection, and service and repair when required, of the  
platform by a trained and authorized employee or an outside service every 30 days or  
before each use cycle if the equipment is used less often than every 30 days. The  
inspection, service, or repair shall be logged to show the date and the signature of the  
authorized employee or outside service and the work done.  
(c) Provide for inspections and operating tests not less than annually or after major  
alterations to determine that all components of the platform, including safety and  
operating equipment, are in compliance with the provisions of these rules. Such  
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inspections and operating tests shall be made by a trained and authorized employee or  
outside service.  
(2) A special inspection of platform governors and secondary brakes shall be made  
not less than annually by an authorized and trained employee or outside service to verify  
that the initiating device for the secondary brake operates at the proper overspeed. If a  
test cannot be made in the field, the initiating device or hoisting machine, or both, shall  
be removed from the building and sent to a shop that is equipped to make such a test.  
(3) When the tested parts are reinstalled, the powered platform shall be reinspected  
before returning it to service.  
History: 1979 AC; 1992 AACS; 2018 AACS.  
R 408.10574 Maintenance.  
Rule 574. (1) The following maintenance shall be performed, when required,  
during the 30-day inspection:  
(a) Replacement of any worn or defective parts noted during the inspections  
prescribed in R 408.10572.  
(b) Electrical connections shall be tightened and controller contactors and relays  
shall be cleaned.  
(c) Gears, shafts, bearings, brakes, and hoisting drums shall be aligned.  
(2) Hoisting ropes shall be reshackled at the non-drum ends at least once every  
2 years. In reshackling a rope, enough shall be cut from the end to remove damaged  
or fatigued portions. The rope shall be retagged and the limit switches reset, if  
necessary.  
(3) Hoisting rope shall be replaced when there are 6 or more broken wires in  
any 1 lay or when the wire rope becomes damaged or is in a deteriorated condition.  
History: 1992 AACS.  
R 408.10575 Hoisting machines.  
Rule 575. (1) The raising and lowering of suspended or supported equipment shall  
be performed only by a hoisting machine.  
(2) Each hoisting machine shall be capable of arresting any overspeed descent of the  
load.  
(3) Each hoisting machine shall be powered only by air, electric, or hydraulic  
sources.  
(4) Each hoisting machine shall be capable of raising or lowering 125% of the rated  
load of the hoist.  
(5) Moving parts of a hoisting machine shall be enclosed or guarded in compliance  
with the provisions of General Industry Safety Standard Part 7 “Guards for Power  
Transmission," as referenced in R 408.10509.  
(6) Flammable liquids shall not be carried on the working platform.  
(7) Winding drums, traction drums, and sheaves and directional sheaves that are  
used in conjunction with hoisting machines shall be sized for the wire rope that is used.  
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(8) Each winding drum shall be provided with a positive means of attaching the wire  
rope to the drum. The attachment shall be capable of developing not less than 4 times the  
rated load of the hoist.  
(9) Each hoisting machine shall be provided with a primary brake and at least 1  
independent secondary brake, each of which shall be capable of stopping and holding not  
less than 125% of the lifting capacity of the hoist.  
(10) The primary brake shall be directly connected to the drivetrain of the hoisting  
machine and shall not be connected through belts, chains, clutches, or set screw-type  
devices. The brake shall automatically set when power to the prime mover is interrupted.  
(11) The secondary brake shall be an automatic emergency type of brake that, if  
actuated during each stopping cycle, shall not engage before the hoist is stopped by the  
primary brake and shall stop and hold the platform within a vertical distance of 24 inches  
(609.6 mm).  
(12) Any component of a hoisting machine that requires lubrication for its protection  
and proper functioning shall be provided with a means for that lubrication to be applied.  
History: 1992 AACS; 2008 AACS; 2016 AACS.  
R 408.10575a Suspended equipment.  
Rule 575a. (1) Each suspended unit component, except for suspension ropes and  
guardrail systems, shall be capable of supporting not less than 4 times the maximum  
intended live load applied or transmitted to that component.  
(2) Each suspended unit component shall be constructed of materials that will  
withstand anticipated weather conditions.  
(3) Each suspended unit shall be provided with a load rating plate that is  
conspicuously located and that states the unit weight and rated load of the suspended unit.  
(4) When the suspension points on a suspended unit are not at the unit ends, the unit  
shall be capable of remaining continuously stable under all conditions of use and position  
of the live load and shall maintain not less than a 1.5 to 1 stability factor against unit  
upset.  
(5) Guide rollers, guide shoes, or building face rollers shall be provided and shall  
compensate for variations in building dimensions and for minor horizontal out-of-level  
variations of each suspended unit.  
(6) Each working platform of a suspended unit shall be secured to the building  
facade by 1 or more of the following methods or by an equivalent method that is in  
compliance with the provisions of R 408.10561 and R 408.10562:  
(a) Continuous.  
(b) Intermittent.  
(c) Button guide engagement.  
(d) Angulated roping.  
(e) Building face rollers.  
(7) Each working platform of a suspended unit shall be provided with a guardrail  
system on all sides, which shall meet the requirements of General Industry Safety and  
Health Standard Part 2 “Walking-Working Surfaces,” as referenced in R 408.10509. All  
of the following provisions apply to the guardrail system:  
(a) The system shall consist of a top guardrail, midrail, and toeboard.  
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(b) The top guardrail shall be not less than 42 inches high and shall be able to  
withstand not less than a 200-pound force in any downward or outward direction.  
(c) The midrail shall be able to withstand not less than a 75-pound (333 n) force in  
any direction.  
(d) The areas between the guardrail and toeboard on the ends and outboard side, and  
the area between the midrail and toeboard on the inboard side, shall be closed with a  
material that is capable of withstanding a load of 100 pounds (45.4 kg.) applied  
horizontally over any area of 1 square foot (.09 m2). All openings in the material shall be  
small enough to prevent the passage of lifelines and potential falling objects that may be  
hazardous to persons below.  
(e) Toeboards shall be capable of withstanding a force of not less than 50 pounds  
(222 n) applied in any direction at any point along the toeboard.  
(f) Toeboards shall be not less than 4 inches in height from the top edge to the level  
of the platform floor.  
(g) Toeboards shall be securely fastened in place at the outermost edge of the  
platform and have not more than 1/4 of an inch (1.3 cm) clearance above the platform.  
(h) Toeboards shall be solid or have an opening that is not more than 1 inch (2.5 cm)  
in the greatest dimension.  
History: 2016 AACS; 2018 AACS.  
R 408.10575b Two- and 4-point suspended working platforms.  
Rule 575b. (1) The 2- and 4-point suspended working platform shall be not less than  
24 inches (610 mm) wide and shall be provided with a minimum of a 12-inch (305 mm)  
wide passage at or past any obstruction on the platform.  
(2) The flooring of the 2- and 4-point suspended working platform shall be of a  
slip-resistant type and shall not have an opening that would allow the passage of lifelines,  
cables, and other potential falling objects.  
(3) The 2- and 4-point suspended working platform shall be provided with a means  
of suspension that will restrict the platform from tilting more than 15 degrees in any  
direction.  
(4) Any cable that is suspended from above the 2- and 4-point suspended working  
platform shall be provided with a means for storage to prevent accumulation of the cable  
on the floor of the platform.  
(5) All operating controls for the vertical travel of the 2- and 4-point suspended  
working platform shall be of the continuous-pressure type and shall be located on the  
platform.  
(6) Each operating station of every 2- and 4-point suspended working platform shall  
be provided with a means of interrupting the power supply to all hoist motors to stop any  
further powered ascent or descent of the platform.  
(7) The maximum rated speed of the 2- and 4-point suspended working platform  
shall not be more than 50 feet per minute (0.3 ms) for single-speed hoists and not more  
than 75 feet per minute (0.4 ms) for multispeed hoists.  
(8) All tools, water tanks, and other accessories shall be secured to prevent their  
movement or accumulation on the floor of the 2- and 4-point suspended working  
platform.  
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(9) Portable fire extinguishers that are in compliance with the provisions of General  
Industry Safety Standard Part 8 “Portable Fire Extinguishers," as referenced in  
R 408.10509, shall be provided and securely attached on all 2- and 4-point suspended  
working platforms.  
(10) Access to and egress from a 2- and 4-point suspended working platform, except  
for those that land directly on a safe surface, shall be provided by stairs, ladders,  
platforms, and runways that are in compliance with the provisions of General Industry  
Safety and Health Standard Part 2 “Walking-Working Surfaces,” as referenced in  
R 408.10509. Access gates shall be self-closing and self-latching.  
(11) Means of access to or egress from a working platform that is 48 inches (1.2 m)  
or more above a safe surface shall be provided with a guardrail system or  
ladder-handrails that are in compliance with the provisions of General Industry Safety  
and Health Standard Part 2 “Walking-Working Surfaces,” as referenced in R 408.10509.  
(12) The 2- and 4-point suspended working platform shall be provided with a  
secondary wire rope suspension system if the platform has overhead structures that  
restrict the emergency egress of employees. A horizontal lifeline or a direct connection  
anchorage shall be provided as part of a personal fall arrest system. The system shall be  
in compliance for each employee on such a platform with the requirements of General  
Industry Safety and Health Standard Part 33 “Personal Protective Equipment" as  
referenced in R 408.10509.  
(13) A vertical lifeline shall be provided as part of a personal fall arrest system. The  
system shall be in compliance with the requirements of General Industry Safety and  
Health Standard Part 33 “Personal Protective Equipment," as referenced in R 408.10509,  
for each employee on a working platform that is suspended by 2 or more wire ropes, if  
the failure of 1 wire rope or suspension attachment will cause the platform to upset. If a  
secondary wire rope suspension is used, vertical lifelines are not required for the personal  
fall arrest system, provided that each employee is attached to a horizontal lifeline  
anchored to the platform.  
History: 2016 AACS; 2018 AACS.  
R 408.10575c Single point suspended working platforms.  
Rule 575c. (1) The requirements of R 408.10575b(1) to (11) apply to a single-point  
working platform.  
(2) Each single-point suspended working platform shall be provided with a  
secondary wire rope suspension system that will prevent the working platform from  
falling if there is a failure of the primary means of support, or if the platform contains  
overhead structures that restrict the egress of the employees. A horizontal lifeline or a  
direct connection anchorage shall be provided, as part of a personal fall arrest system that  
is in compliance with the requirements of General Industry Safety and Health Standard  
Part 33 “Personal Protective Equipment," as referenced in R 408.10509, for each  
employee on the platform.  
History: 2016 AACS; 2018 AACS.  
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R 408.10575d Ground-rigged working platforms.  
Rule 575d. (1) The ground-rigged working platform shall be in compliance with all  
of the requirements of R 408.10575b(1) to (11).  
(2) After each day's use, the power supply within the building shall be disconnected  
from a ground-rigged working platform, and the platform shall be either disengaged from  
its suspension points or secured and stored at grade.  
History: 2016 AACS.  
R 408.10575e Intermittently stabilized platforms.  
Rule 575e. (1) The intermittently stabilized platform shall be in compliance with the  
requirements of R 408.10575b (1) to (13).  
(2) Each stabilizer tie shall be equipped with a quick-connect and quick-disconnect  
device that cannot be accidentally disengaged, that is for attachment to the building  
anchor, and that is resistant to adverse environmental conditions.  
(3) The platform shall be provided with a stopping device that will interrupt the hoist  
power supply if the platform contacts a stabilizer tie during its ascent.  
(4) Building face rollers shall not be placed at the anchor setting if exterior anchors  
are used on the building face.  
(5) Stabilizer ties that are used on intermittently stabilized platforms shall allow for  
the specific attachment length that is needed to effect the predetermined angulation of the  
suspended wire rope. The specific attachment length shall be maintained at all building  
anchor locations.  
(6) The intermittently stabilized platform shall be in continuous contact with the face  
of the building during ascent and descent.  
(7) The attachment and removal of stabilizer ties shall not require the horizontal  
movement of the platform.  
(8) The platform-mounted equipment and its suspension wire ropes shall not be  
physically damaged by the loads from the stabilizer tie or its building anchor. The  
platform, platform-mounted equipment, and wire ropes shall be able to withstand a load  
that is not less than twice the ultimate strength of the stabilizer tie.  
History: 2016 AACS; 2018 AACS.  
R 408.10575f Button-guide stabilized platforms.  
Rule 575f. (1) The button-guide stabilized platform shall be in compliance with the  
requirements of R 408.10575b(1) to (13).  
(2) Each guide track on the button-guide stabilized platform shall engage a  
minimum of 2 guide buttons during any vertical travel of the platform after the initial  
button engagement.  
(3) Each guide track on a button-guide stabilized platform that is part of a  
roof-rigged system shall be provided with a storage position on the platform.  
(4) Each guide track on the button-guide stabilized platform shall be sufficiently  
maneuverable by platform occupants to permit easy engagement of the guide buttons and  
easy movement into and out of the guide track's storage position on the platform.  
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(5) Two guide tracks shall be mounted on the button-guide stabilized platform and  
shall provide continuous contact with the building face.  
(6) The load-carrying components of the button guide stabilization system that  
transmit the load into the platform shall be capable of supporting the weight of the  
platform or provision shall be made in the guide track connectors or platform attachments  
to prevent the weight of the platform from being transmitted to the platform attachments.  
History: 2016 AACS.  
R 408.10575g Supported equipment.  
Rule 575g. (1) Supported equipment shall maintain a vertical position in respect to  
the face of the building by means other than friction.  
(2) Cog wheels or equivalent means shall be incorporated to provide climbing  
traction between the supported equipment and the building guides.  
(3) Additional guide wheels or shoes shall be incorporated as may be necessary to  
ensure that the drive wheels are continuously held in positive engagement with the  
building guides.  
(4) Launch guide mullions that are indexed to the building guides and that are  
retained in alignment with the building guides shall be used to align drive wheels that  
enter the building guides.  
(5) Manned platforms that are used on supported equipment shall be in compliance  
with the requirements of R 408.10575b (1), (2), and (4) to (11) with respect to suspended  
equipment.  
History: 2016 AACS.  
R 408.10575h Suspension wire ropes and rope connections.  
Rule 575h. (1) Each specific installation shall use suspension wire ropes or  
combination cable and connections that are in compliance with the specifications  
recommended by the manufacturer of the hoisting machine that is used. Connections  
shall be capable of developing not less than 80% of the rated breaking strength of the  
wire rope.  
(2) Each suspension rope shall have a design factor of not less than 10. The design  
factor is the ratio of the rated strength of the suspension wire rope to the rated working  
load and shall be calculated using the following formula:  
F = S(N)  
W
Where:  
F
S
N
Design factor  
Manufacturer’s rated strength of 1 suspension rope.  
Number of suspension ropes under 1 load  
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W
Rated working load on all ropes at any point of travel.  
(3) Suspension wire rope grade shall be at least improved plow steel or equivalent.  
(4) Suspension wire ropes shall be sized to be in compliance with the required  
design factor, but shall not be less than 5/16 of an inch (7.94 mm) in diameter.  
(5) A reverse bend in wire rope shall not be permitted.  
(6) A bend radius in wire rope shall not be less than 20 times the wire rope diameter.  
(7) Wire rope shall be inspected and maintained as specified in the provisions of  
R 408.10582.  
History: 2016 AACS.  
R 408.10576 Tags.  
Rule 576. (1) A corrosion-resistant tag shall be securely attached to 1 of the wire  
rope fastenings when a suspension wire rope is to be used at a specific location and will  
remain in that location. This tag shall bear all of the following wire rope data:  
(a) The diameter in inches or millimeters, or both.  
(b) Construction classification.  
(c) Whether non-preformed or preformed.  
(d) The grade of materials.  
(e) The manufacturer's rated strength.  
(f) The manufacturer's name.  
(g) The month and year the ropes were installed.  
(h) The name of the person or company that installed the ropes.  
(2) A new tag shall be installed at each rope renewal.  
(3) The original tag shall be stamped with the date of the resocketing or the original  
tag shall be retained and a supplemental tag shall be provided when ropes are resocketed.  
The supplemental tag shall show the date of resocketing and the name of the person or  
company that resocketed the rope.  
(4) Winding drum-type hoists shall contain not less than 3 wraps of the suspension  
wire rope on the drum when the suspended unit has reached the lowest possible point of  
its vertical travel.  
(5) Traction drum and sheave-type hoists shall be provided with a wire rope that is  
of a sufficient length to reach the lowest possible point of vertical travel of the suspended  
unit and with an additional length of the wire rope that is not less than 4 feet (1.2 m). The  
lengthening or repairing of suspension wire rope is prohibited. Babbitted fastenings for  
suspension wire rope are prohibited.  
History: 1992 AACS; 2016 AACS.  
R 408.10577 Control circuits; power circuits; components.  
Rule 577. (1) Electrical wiring and equipment shall be in compliance with the  
requirements specified in General Industry Safety Standard Part 39 “Design Safety  
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Standards for Electrical Systems,” as referenced in R 408.10509, except as otherwise  
required by these rules.  
(2) An electrical runway conductor system shall be of a type that is designed for use  
in exterior locations and shall be located so that the system does not come into contact  
with accumulated snow or water.  
(3) Cables shall be protected against damage that results from over-tensioning or  
from other causes.  
(4) Devices shall be included in the control system for the equipment which will  
provide protection against electrical overloads, 3-phase reversal, and phase failure. The  
control system shall have a separate method, which shall be independent of the direction  
control circuit, for breaking the power circuit if there is an emergency or malfunction.  
(5) Suspended or supported equipment shall have a control system that will require  
the operator of the equipment to follow predetermined procedures.  
(6) All of the following requirements apply to electrical protection devices:  
(a) On installations where the carriage does not have a stability factor of at least 4  
against overturning, an electrical contact or contacts shall be provided and connected so  
that the operating devices for the suspended or supported equipment shall be operative  
only when the carriage is located and mechanically retained at an established operating  
point.  
(b) Overload protection shall be provided in the hoisting or suspension system to  
protect against the equipment operating in the "up" direction with a load of more than  
125% of the rated load of the platform.  
(c) An automatic detector shall be provided for each suspension point which will  
interrupt power to all hoisting motors for travel in the "down" direction and which will  
apply the primary brakes if any suspension wire rope becomes slack.  
A
continuous-pressure rigging-bypass switch that is designed for use during rigging is  
permitted. This switch shall only be used by authorized personnel during rigging.  
(d) Upper and lower directional switches that are designed to prevent the travel of  
suspended units beyond safe upward and downward levels shall be provided.  
(e) Emergency stop switches shall be provided on remote controlled, roof-powered  
platforms that are adjacent to each control station on the platform.  
(f) Cables that are in constant tension shall have overload devices which will prevent  
the tension in the cable from interfering with the load-limiting device or with the platform  
roll-limiting device. The setting of these devices shall be coordinated with other overload  
settings at the time the system is designed and shall be clearly indicated on or near the  
device. The device shall interrupt the equipment travel in the "down" direction.  
History: 1992 AACS; 2016 AACS.  
R 408.10578 Inspection and tests.  
Rule 578. (1) All completed building maintenance equipment installations shall be  
inspected and tested in the field before being placed in initial service to determine that all  
parts of the installation are in compliance with applicable requirements of these rules, and  
that all safety and operating equipment is functioning as required.  
(2) A similar inspection and test shall be made after any major alteration to an  
existing installation.  
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(3) A hoist in an installation shall not be subjected to a load that is more than 125%  
of its rated load.  
History: 1992 AACS; 2016 AACS.  
R 408.10579 Periodic inspections and tests.  
Rule 579. (1) Related building supporting structures shall undergo periodic  
inspection by a competent person at intervals of not more than 12 months.  
(2) All parts of the equipment, including control systems, shall be inspected and,  
where necessary, tested by a competent person at intervals specified by the manufacturer  
and supplier, but not more than 12-month intervals, to determine that equipment parts are  
in safe operating condition. Parts that are subject to wear, such as wire ropes, bearings,  
gears, and governors, shall be inspected or tested to determine that they have not worn to  
such an extent as to affect the safe operation of the installation.  
(3) The owner shall keep a certification record of each inspection and test required.  
The record shall include all of the following information:  
(a) The date of the inspection.  
(b) The signature of the person who performed the inspection.  
(c) The number, or other identifier, of the building support structure and equipment  
that was inspected. This certification record shall be kept readily available for review by  
the director of the Michigan department of licensing and regulatory affairs or his or her  
representative and by the employer.  
(4) Working platforms and their components shall be inspected by the employer for  
visible defects before every use and after each occurrence that could affect the platform's  
structural integrity.  
History: 1992 AACS; 2013 AACS; 2016 AACS.  
R 408.10580 Maintenance inspections and tests.  
Rule 580. (1) A maintenance inspection and, where necessary, a test shall be made  
of each platform installation every 30 days. If the work cycle is less than 30 days, such  
inspection and test shall be made before each work cycle. This inspection and test shall  
follow the procedures recommended by the manufacturer and shall be made by a  
competent person.  
(2) The building owner shall keep a certification record of each inspection and test  
performed. The record shall contain all of the following information:  
(a) The date of the inspection and test.  
(b) The signature of the person who performed the inspection or test.  
(c) An identifier for the platform installation that was inspected. The certification  
record shall be kept readily available for review by the director of the Michigan  
department of licensing and regulatory affairs or his or her designated representative and  
by the employer.  
History: 1992 AACS; 2013 AACS; 2016 AACS.  
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R 408.10581 Special inspection of governors and secondary brakes.  
Rule 581. (1) Governors and secondary brakes shall be inspected and tested at  
intervals specified by the manufacturer and supplier, but the interval shall not be more  
than every 12 months.  
(2) The results of the inspection and test shall confirm that the initiating  
device for the secondary braking system operates at the proper overspeed.  
(3) The results of the inspection and test shall confirm that the secondary  
brake is functioning properly.  
(4) If any hoisting machine or initiating device for the secondary brake system is  
removed from the equipment for testing, all reinstalled and directly related  
components shall be reinspected before returning the equipment installation to  
service.  
(5) Inspection of governors and secondary brakes shall be performed by a  
competent person.  
(6) The secondary brake governor and actuation device shall be tested before  
each daily use. Where testing is not feasible, a visual inspection of the brake shall be  
made to ensure that it is free to operate.  
History: 1992 AACS.  
R 408.10582 Suspension wire rope maintenance; inspection and replacement.  
Rule 582. (1) Any of the following conditions or combination of conditions are  
because for removal of the wire rope:  
(a) In any length of 8 diameters, the total number of visible broken wires is more  
than 6 in 1 rope lay or 3 wires in 1 strand.  
(b) The wire rope has been kinked, crushed, or bird-caged or has sustained any other  
damage that distorts the wire rope structure.  
(c) The wire rope shows heat or corrosive damage.  
(d) The wire rope contains a broken wire within 18 inches (460.8 mm) of the end  
attachment.  
(2) Wire rope that is bent to form an eye over a bolt or rod that has a diameter that is  
less than 4 times the rope diameter shall be equipped with a metal thimble.  
(3) End fittings should be swagged or zinc-poured sockets.  
(4) Where wire clips are used, the provisions of table 8 shall be followed and the  
u-bolts shall be installed on the dead end or short end of the wire rope.  
(5) Wire rope shall be stored in a manner to prevent damage or deterioration.  
(6) Before cutting wire rope, a seizing shall be placed on each side of the cut on  
preformed wire rope, 2 seizings shall be placed on each side of 7/8 inch size or smaller  
nonpreformed wire rope, and 3 seizings shall be placed on each side of 1 inch or larger  
size nonpreformed wire rope.  
(7) Wire rope shall be maintained in a lubricated condition over its entire length with  
the same type of lubricant that is used by the manufacturer.  
(8) Suspension wire ropes shall be maintained and used in accordance with the  
procedures recommended by the wire rope manufacturer.  
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(9) Suspension wire rope shall be inspected by a competent person for visible  
defects and gross damage to the rope before every use and after each occurrence that  
might affect the wire rope's integrity.  
(10) A thorough inspection of suspension wire ropes in service shall be made once a  
month. Suspension wire ropes that have been inactive for 30 days or more shall have a  
thorough inspection before they are placed into service. These thorough inspections of  
suspension wire ropes shall be performed by a competent person.  
(11) The need for replacement of suspension wire rope shall be based on its  
condition. A wire rope shall be removed for any of the following conditions:  
(a) Evidence of core failure. A lengthening of rope lay, protrusion of the rope core,  
and a reduction in rope diameter suggests core failure.  
(b) Outer wire wear is more than 1/3 of the original outer wire diameter.  
(c) Any other condition that the competent person determines has significantly  
affected the integrity of the rope.  
(12) The owner shall keep a certification record of each monthly inspection of a  
suspension wire rope which shall be verified by the employer. The record shall include  
the date of the inspection and a number or other identifier of the wire rope that was  
inspected. The record of inspection shall be made available for review by the director of  
the Michigan Department of Licensing and Regulatory Affairs or his or her designated  
representative and by the employer.  
History: 1992 AACS; 2013 AACS; 2016 AACS; 2018 AACS.  
R 408.10583 Fiber rope maintenance; inspection and replacement.  
Rule 583. (1) An employer shall ensure that fiber rope shall be inspected visually  
before the start of each daily use as follows:  
(a) Externally for any of the following conditions:  
(i) Abrasions.  
(ii) Cut or broken fibers.  
(iii) Decay.  
(iv) Burns.  
(v) Lack of strength.  
(vi) Softness.  
(vii) Variation in size or roundness of the strands.  
(b) Internally, by separating the strands at 3-foot intervals, for any of the following  
conditions:  
(i) Broken fibers.  
(ii) Presence of grit.  
(iii) Mildew or mold.  
(iv) Color change of the fibers.  
(v) Powdering.  
(vi) Short loose fibers. A rope that has any of the conditions specified in this rule  
shall be replaced or returned to the manufacturer for repair.  
(2) A fiber rope shall be stored in a dry room in coils or on a reel.  
(3) A wet fiber rope shall be dried by placing it in the sunshine or a warm room  
hanging loosely over a rounded peg or hook.  
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(4) A fiber rope shall not be kinked or run over sharp corners, shall not be used  
when frozen, and shall not be left in freezing temperatures when wet.  
(5) A fiber rope that is subjected to an impact load that is equal to or more than its  
rated capacity shall be replaced.  
(6) A thimble shall be used with fiber rope pursuant to the provisions of  
R 408.10581(2).  
History: 1992 AACS; 2016 AACS.  
R 408.10584 Synthetic rope maintenance; inspection and replacement.  
Rule 584. (1) An employer shall ensure that synthetic rope shall be inspected  
visually before the start of each job for all of the following conditions:  
(a) Abrasions.  
(b) Cut or broken fibers.  
(c) Burns.  
(d) Melted fibers.  
(e) Variation in size or roundness of the strands. A rope that has any of these  
conditions shall be replaced or returned to the manufacturer for repair.  
(2) Because of the variance in manufacturing methods, the manufacturer's  
recommendations shall be followed.  
(3) A synthetic rope shall not be kinked, run over sharp corners, used when frozen,  
or left in freezing temperatures when wet.  
(4) A synthetic rope that is subjected to an impact load that is equal to or more than  
its rated capacity shall be replaced.  
(5) A thimble shall be used with synthetic rope pursuant to the provisions of  
R 408.10581(2).  
History: 1992 AACS; 2016 AACS.  
R 408.10585 Hoist inspection; maintenance and cleaning.  
Rule 585. (1) Before lowering personnel below the top elevation of the building, a  
hoist shall be tested each day in the lifting direction with the intended load to make  
certain it has sufficient capacity to raise the personnel back to the boarding level.  
(2) All parts of the equipment that affect the safe operation of a hoist shall be  
maintained in proper working order so that the parts perform the functions for which they  
were intended. The equipment shall be taken out of service when it is not in proper  
working order.  
(3) Control or power contacts and relays shall be kept clean.  
(4) All other equipment parts shall be kept clean if their proper functioning would be  
affected by the presence of dirt or other contaminants.  
History: 1992 AACS; 2016 AACS.  
R 408.10586 Periodic resocketing of wire rope fastenings.  
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Rule 586. (1) Hoisting ropes that utilize poured socket fastenings shall be resocketed  
at the non-drum ends at intervals of not more than 24 months. In resocketing the  
ropes, a sufficient length shall be cut from the end of the rope to remove damaged or  
fatigued portions.  
(2) Resocketed ropes shall be in compliance with the requirements  
408.10581.  
(3) Limit switches that are affected by the resocketed ropes shall be reset, if  
necessary.  
of  
R
History: 1992 AACS.  
R 408.10587 Roof systems; maintenance.  
Rule 587. Roof track systems, tie downs, and similar equipment shall  
be  
maintained in proper working order so that they perform the functions for which they  
were intended.  
History: 1992 AACS.  
R 408.10588 Building face guiding members; maintenance.  
Rule 588. T-rails, indented mullions, and equivalent guides that are located in  
the face of a building shall be maintained in proper working order so that they  
perform the functions for which they were intended.  
Brackets for cable stabilizers shall similarly be maintained in proper working  
order.  
History: 1992 AACS.  
R 408.10589 Inoperative safety devices.  
Rule 589. A person shall not render a required safety device or electrical protective  
device inoperative, except as necessary for tests, inspections, and maintenance.  
Immediately upon completion of such tests, inspections, and maintenance, the device  
shall be restored to its normal operating condition.  
History: 1992 AACS; 2016 AACS.  
R 408.10590. Platform operator training.  
Rule 590. (1) Working platforms shall be operated only by persons who are proficient in  
the operation, safe use, and inspection of the particular working platform to be operated.  
(2) All employees who operate working platforms shall be trained in all of the following  
areas:  
(a) Recognition of, and preventative measures for, the safety hazards that are associated  
with the employee's individual work tasks.  
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(b) General recognition and prevention of safety hazards that are associated with the use  
of working platforms.  
(c) Emergency action plan procedures.  
(d) Work procedures.  
(e) Personal fall arrest system inspection, care, use, and system performance.  
(3) The training of employees in the operation and inspection of working platforms shall  
be done by a competent person.  
(4) Written work procedures for the operation, safe use, and inspection of working  
platforms shall be provided for employee training. Pictorial methods of instruction may  
be used in place of written work procedures if employee communication is improved  
through the use of this method. The operating manuals that are supplied by the  
manufacturers for platform system components can serve as the basis for these  
procedures.  
(5) An employer shall certify that employees have been trained in the operation and  
inspection of a working platform by preparing a certification record that includes all of  
the following information:  
(a) The identity of the person trained.  
(b) The signature of the employer or the person who conducted the training.  
(c) The date that training was completed.  
The certification record shall be prepared at the completion of the training and shall be  
maintained in a file for the duration of the employee's employment. The certification  
record shall be kept readily available for review by the director of the Michigan  
department of licensing and regulatory affairs or his or her designated representative.  
History: 1992 AACS; 2013 AACS.  
R 408.10591 Operations use.  
Rule 591. (1) Working platforms shall not be loaded in excess of the rated load as  
stated on the platform load rating plate.  
(2) Employees shall be prohibited from working on snow, ice, or other slippery  
material that covers a platform, except to remove such materials.  
(3) Adequate precautions shall be taken to protect the platform, wire ropes, and  
lifelines from damage due to acids or other corrosive substances. The precautions taken  
shall be in accordance with the recommendations of the corrosive substance producer,  
supplier, platform manufacturer, or other equivalent information sources. Platform  
members that have been exposed to acids or other corrosive substances shall be washed  
down after each use with a neutralizing solution at a frequency recommended by the  
corrosive substance producer or supplier.  
(4) Platform members, wire ropes, and lifelines shall be protected when using a  
heat-producing process. Wire ropes and lifelines that have been contacted by the  
heat-producing process shall be considered to be permanently damaged and shall not be  
used.  
(5) A platform shall not be operated in winds of more than 25 miles per hour (40.2  
km/hr), except to move the platform from an operating to a storage position. Wind speed  
shall be determined based on the best available information, which includes on-site  
anemometer readings and local weather forecasts that predict wind velocities for the area.  
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(6) On exterior installations, an anemometer shall be mounted on the platform to  
determine on-site wind velocities before and during use of the platform. The anemometer  
may be a portable (hand-held) unit that is temporarily mounted during platform use.  
(7) Tools, materials, and debris that are not related to the work in progress shall not  
be allowed to accumulate on platforms. Stabilizer ties shall be located so as to allow  
unencumbered passage along the full length of the platform and shall be of such length so  
as not to become entangled in rollers, hoists, or other machinery.  
History: 1992 AACS; 2016 AACS.  
R 408.10592 Personal fall protection.  
Rule 592. Employees on working platforms shall be protected by a personal fall  
arrest system that is in compliance with the requirements of General Industry Safety and  
Health Standard Part 33 “Personal Protective Equipment," as referenced in R 408.10509.  
APPENDIX D – EXISTING INSTALLATIONS  
MANDATORY  
Use of the Appendix  
Appendix D sets out the mandatory building and equipment requirements for  
applicable permanent installations completed after August 27, 1971, and no later than  
July 23, 1990, which are exempt from R 408.10501, R 408.10502, R 408.10503 to  
R 408.10508, R 408.10518, R 408.10561 to R 408.10567, R 408.10568 to R 408.10569,  
and R 408.10575 to R 408.10577 of this standard.  
The requirements in Appendix D are essentially the same as unrevised building and  
equipment provisions which previously were designated as R 408.10501, R 408.10502,  
R 408.10518, and R 408.10503 to R 408.10508, and which were effective on November  
1, 1974.  
Note: All existing installations subject to this appendix shall also comply with  
R 408.10574(2), R 408.10578 to R 408.10582, and R 408.10585 to R 408.10592 of this  
standard.  
(A) "DEFINITIONS APPLICABLE TO THIS APPENDIX"  
(1) "Angulated roping." A system of platform suspension in which the upper wire  
rope sheaves or suspension points are closer to the plane of the building face than the  
corresponding attachment points on the platform, thus causing the platform to press  
against the face of the building during its vertical travel.  
(2) "ANSI" American National Standards Institute.  
(3) "Babbitted fastenings." The method of providing wire rope attachments in which  
the ends of the wire strands are bent back and are held in a tapered socket by means of  
poured molten babbitt metal.  
(4) "Brake" - "disc type." A brake in which the holding effect is obtained by  
frictional resistance between 1 or more faces of discs keyed to the rotating member to be  
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held and fixed discs keyed to the stationary or housing member (pressure between the  
discs being applied axially).  
(5) "Brake - self-energizing band type." An essentially unidirectional brake in which  
the holding effect is obtained by the snubbing action of a flexible band wrapped about a  
cylindrical wheel or drum affixed to the rotating member to be held, the connections and  
linkages being so arranged that the motion of the brake wheel or drum will act to increase  
the tension or holding force of the band.  
(6) "Brake - shoe type." A brake in which the holding effect is obtained by applying  
the direct pressure of 2 or more segmental friction elements held to a stationary member  
against a cylindrical wheel or drum affixed to the rotating member to be held.  
(7) "Building face rollers." A specialized form of guide roller designed to contact a  
portion of the outer face or wall structure of the building, and to assist in stabilizing the  
operators' platform during vertical travel.  
(8) "Continuous pressure." Operation by means of buttons or switches, any 1 of  
which may be used to control the movement of the working platform or roof car, only as  
long as the button or switch is manually maintained in the actuating position.  
(9) "Control." A system governing starting, stopping, direction, acceleration, speed,  
and retardation of moving members.  
(10) "Controller." A device or group of devices, usually contained in a single  
enclosure, that serves to control in some predetermined manner the apparatus to which it  
is connected.  
(11) "Electrical ground." A conducting connection between an electrical circuit or  
equipment and the earth, or some conducting body which serves in place of the earth.  
(12) "Guide roller." A rotating, bearing-mounted, generally cylindrical member,  
operating separately or as part of a guide shoe assembly, attached to the platform, and  
providing rolling contact with building guideways, or other building contact members.  
(13) "Guide shoe." An assembly of rollers, slide members, or the equivalent,  
attached as a unit to the operators' platform, and designed to engage with the building  
members provided for the vertical guidance of the operators' platform.  
(14) "Interlock." A device actuated by the operation of some other device with  
which it is directly associated, to govern succeeding operations of the same or allied  
devices.  
(15) "Operating device." A pushbutton, lever, or other manual device used to actuate  
a control.  
(16) "Powered platform." Equipment to provide access to the exterior of a building  
for maintenance, consisting of a suspended power-operated working platform, a roof car,  
or other suspension means, and the requisite operating and control devices.  
(17) "Rated load." The combined weight of employees, tools, equipment, and other  
material which the working platform is designed and installed to lift.  
(18) "Relay, direction." An electrically energized contactor responsive to an  
initiating control circuit, which in turn causes a moving member to travel in a particular  
direction.  
(19) "Relay, potential for vertical travel." An electrically energized contactor  
responsive to initiating control circuit, which in turn controls the operation of a moving  
member in both directions. This relay usually operates in conjunction with direction  
relays, as covered under the definition, "relay, direction."  
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(20) "Roof car." A structure for the suspension of a working platform, providing for  
its horizontal movement to working positions.  
(21) "Roof-powered platform." A powered platform having the raising and lowering  
mechanism located on a roof car.  
(22) "Self-powered platform." A powered platform having the raising and lowering  
mechanism located on the working platform.  
(23) "Traveling cable." A cable made up of electrical or communication conductors  
or both, and providing electrical connection between the working platform and the roof  
car or other fixed point.  
(24) "Weatherproof." Equipment so constructed or protected that exposure to the  
weather will not interfere with its proper operation.  
(25) "Working platform." The suspended structure arranged for vertical travel that  
provides access to the exterior of the building or structure.  
(26) "Yield point." The stress at which the material exhibits a permanent set of 0.2  
percent.  
(27) "Zinced fastenings." The method of providing wire rope attachments in which  
the splayed or fanned wire ends are held in a tapered socket by means of poured molten  
zinc.  
(B) "GENERAL REQUIREMENTS"  
(1) "Design requirements." All powered platform installations for exterior building  
maintenance completed as of August 27, 1971, but not later than 180 days after  
November 1, 1974, shall meet all of the design, construction, and installation  
requirements of Part II and III of ANSI A120.1 “Safety Requirement for Powered  
Platforms for Exterior Building Maintenance,” 1970 edition, as adopted in R 408.40509,  
and of this appendix. References shall be made to appropriate parts of ANSI A120.1  
1970 edition for detail specifications for equipment and special installations.  
(2) "Limitation." The requirements of this appendix apply only to electric powered  
platforms. It is not the intent of this appendix to prohibit the use of other types of power.  
Installation of powered platforms using other types of power is permitted, provided such  
platforms have adequate protective devices for the type of power used, and otherwise  
provide for reasonable safety of life and limb to users of equipment and to others who  
may be exposed.  
(3) "Types of powered platforms.”  
(i) For the purpose of applying this appendix, powered platforms are divided into 2  
basic types, Type F and Type T.  
(ii) Powered platforms designated as Type F shall meet all the requirements in Part  
II of ANSI A120.1 “Safety Requirement for Powered Platforms for Exterior Building  
Maintenance,” 1970 edition, as adopted in R 408.40509. A basic requirement of Type F  
equipment is that the work platform is suspended by at least 4 wire ropes and designed so  
that failure of any 1 wire rope will not substantially alter the normal position of the  
working platform. Another basic requirement of Type F equipment is that only 1 layer of  
hoisting rope is permitted on winding drums. Type F powered platforms may be either  
roof-powered or self-powered.  
(iii) Powered platforms designated as Type T shall meet all the requirements in Part  
III of ANSI A120.1 “Safety Requirement for Powered Platforms for Exterior Building  
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Maintenance,” except for section 28, “Safety Belts and Life Lines,” 1970 edition, as  
adopted in R 408.40509. A basic requirement of Type T equipment is that the working  
platform is suspended by at least 2 wire ropes. Failure of 1 wire rope would not permit  
the working platform to fall to the ground, but would upset its normal position. Type T  
powered platforms may be either roof-powered or self-powered.  
(iv) The requirements of this section apply to powered platforms with winding drum  
type hoisting machines. It is not the intent of this section to prohibit powered platforms  
using other types of hoisting machines such as, but not limited to, traction drum hoisting  
machines, air powered machines, hydraulic powered machines, and internal combustion  
machines. Installation of powered platforms with other types of hoisting machines is  
permitted, provided adequate protective devices are used, and provided reasonable safety  
of life and limb to users of the equipment and to others who may be exposed is assured.  
(v) Both Type F and Type T powered platforms shall comply with the requirements  
of Appendix C of this rule.  
(C) "TYPE F POWERED PLATFORMS"  
(1) "Roof car, general.”  
(i) A roof car shall be provided whenever it is necessary to move the working  
platform horizontally to working or storage positions.  
(ii) The maximum rated speed at which a power traversed roof car may be moved in  
a horizontal direction shall be 50 feet per minute.  
(2) "Movement and positioning of roof car.”  
(i) Provision shall be made to protect against having the roof car leave the roof or  
enter roof areas not designed for travel.  
(ii) The horizontal motion of the roof cars shall be positively controlled so as to  
ensure proper movement and positioning of the roof car.  
(iii) Roof car positioning devices shall be provided to ensure that the working  
platform is placed and retained in proper position for vertical travel and during storage.  
(iv) Mechanical stops shall be provided to prevent the traversing of the roof car  
beyond its normal limits of travel. Such stops shall be capable of withstanding a force  
equal to 100 percent of the inertial effect of the roof car in motion with traversing power  
applied.  
(v)(a) The operating device of a power-operated roof car for traversing shall be  
located on the roof car, the working platform, or both, and shall be of the continuous  
pressure weatherproof electric type. If more than 1 operating device is provided, the  
operating device shall be so arranged that traversing is possible only from 1 operating  
device at a time.  
(b) The operating device shall be so connected that it is not operable until both of the  
following:  
(1) The working platform is located at its uppermost position of travel and is not in  
contact with the building face or fixed vertical guides in the face of the building; and  
(2) All protective devices and interlocks are in a position for traversing.  
(3) "Roof car stability." Roof car stability shall be determined by either paragraph  
(c)(3)(i) or (ii) of this appendix, whichever is greater.  
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(i) The roof car shall be continuously stable, considering overturning moment as  
determined by 125 percent rated load, plus maximum dead load and the prescribed wind  
loading.  
(ii) The roof car and its anchorages shall be capable of resisting accidental  
over-tensioning of the wire ropes suspending the working platform and this calculated  
value shall include the effect of 1 1/2 times the value. For this calculation, the  
simultaneous effect of 1/2 wind load shall be included, and the design stresses shall not  
exceed those referred to in paragraph (b)(1) of this appendix.  
(iii) If the load on the motors is at any time in excess of 3 times that required for  
lifting the working platform with its rated load, the motor shall stall.  
(4)"Access to the roof car." Safe access to the roof car and from the roof car to the  
working platform shall be provided. If the access to the roof car at any point of its travel  
is not over the roof area or where otherwise necessary for safety, then self-closing,  
self-locking gates shall be provided. Access to and from roof cars shall comply with the  
requirements of General Industry Safety and Health Standard Part 2 “Walking-Working  
Surfaces,” as referenced in R 408.10509.  
(5) "Means for maintenance, repair, and storage." Means shall be provided to run the  
roof car away from the roof perimeter, where necessary, and to provide a safe area for  
maintenance, repairs, and storage. Provisions shall be made to secure the machine in the  
stored position. For stored machines subject to wind forces, see special design and  
anchorage requirements for "wind forces" in Part II, section 10.5.1.1 of ANSI A120.1  
“Safety Requirement for Powered Platforms for Exterior Building Maintenance,” 1970  
edition, as adopted in R 408.40509.  
(6) "General requirements for working platforms." The working platform shall be of  
girder or truss construction and shall be adequate to support its rated load under any  
position of loading, and comply with the provisions set forth in section 10 of ANSI  
A120.1 “Safety Requirement for Powered Platforms for Exterior Building Maintenance,”  
1970 edition, as adopted in R 408.40509,  
(7) "Load rating plate." Each working platform shall bear a manufacturer's load  
rating plate, conspicuously posted; stating the maximum permissible rated load. Load  
rating plates shall be made of noncorrosive material and shall have letters and figures  
stamped, etched, or cast on the surface. The minimum height of the letters and figures  
shall be 1/4 inch.  
(8) "Minimum size." The working platform shall have a minimum net width of 24  
inches.  
(9) "Guardrails." Working platforms shall be furnished with permanent guard rails  
not less than 36 inches high, and not more than 42 inches high at the front of building  
side. At the rear, and on the sides, the rail shall not be less than 42 inches high. An  
intermediate guardrail shall be provided around the entire platform between the top  
guardrail and the toeboard.  
(10) "Toeboards." A 4-inch toeboard shall be provided along all sides of the working  
platform.  
(11) "Open spaces between guardrails and toeboards." The spaces between the  
intermediate guardrail and platform toeboard on the building side of the working  
platform, and between the top guardrail and the toeboard on other sides of the platform,  
shall be filled with metallic mesh or similar material that will reject a ball 1 inch in  
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diameter. The installed mesh shall be capable of withstanding a load of 100 pounds  
applied horizontally over any area of 144 square inches. If the space between the  
platform and the building face does not exceed 8 inches, and the platform is restrained by  
guides, the mesh may be omitted on the front side.  
(12) "Flooring." The platform flooring shall be of the nonskid type, and if of open  
construction, shall reject a 9/16 - inch diameter ball, or be provided with a screen below  
the floor to reject a 9/16 - inch diameter ball.  
(13) "Access gates." Where access gates are provided, access gates shall be  
self-closing and self-locking.  
(14) "Operating device for vertical movement of the working platform.”  
(i) The normal operating device for the working platform shall be located on the  
working platform and shall be of the continuous pressure weatherproof electric type.  
(ii) The operating device shall be operable only when all electrical protective  
devices and interlocks on the working platform are in position for normal service, and the  
roof car, if provided, is at an established operating point.  
(15) "Emergency electric operative device.”  
(i) In addition, on roof-powered platforms, an emergency electric operating device  
shall be provided near the hoisting machine for use in the event of failure of the normal  
operating device for the working platform, or failure of the traveling cable system. The  
emergency operating device shall be mounted in a locked compartment and shall have a  
legend mounted thereon reading: "for Emergency Operation Only. Establish  
Communication With Personnel on Working Platform Before Use."  
(ii) A key for unlocking the compartment housing the emergency operating device  
shall be mounted in a break-glass receptacle located near the emergency operating  
device.  
(16) "Manual cranking for emergency operation." Emergency operation of the main  
drive machine may be provided to allow manual cranking. This provision for manual  
operation shall be designed so that not more than 2 persons will be required to perform  
this operation. The access to this provision shall include a means to automatically make  
the machine inoperative electrically while under the emergency manual operation. The  
design shall be such that the emergency brake is operative at or below governor tripping  
speed during manual operation.  
(17) "Arrangement and guarding of hoisting equipment.”  
(i) Hoisting equipment shall consist of a power-driven drum or drum contained in  
the roof car, also known as roof-powered platforms, or contained on the working  
platform, also known as self-powered platform.  
(ii) The hoisting equipment shall be power-operated in both up and down directions.  
(iii) Guard or other protective devices shall be installed wherever rotating shafts or  
other mechanisms or gears may expose personnel to a hazard.  
(iv) Friction devices or clutches shall not be used for connecting the main driving  
mechanism to the drum or drums. Belt or chain-driven machines are prohibited.  
(18) "Hoisting motors.”  
(i) Hoisting motors shall be electric and of weather-proof construction.  
(ii) Hoisting motors shall be in conformance with applicable provisions of paragraph  
(c)(22) of this appendix, Electrical Wiring and Equipment.  
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(iii) Hoisting motors shall be directly connected to the hoisting machinery. Motor  
couplings, if used, shall be of steel construction.  
(19) "Brakes." The hoisting machine or machines shall have 2 independent braking  
means, each designed to stop and hold the working platform with 125 percent of rated  
load.  
(20) "Hoisting ropes and rope connections.”  
(i) Working platforms shall be suspended by wire ropes of either 6 X 19 or 6 X 37  
classification, preformed or non-preformed.  
(ii) [Reserved]  
(iii) The minimum factor of safety is 10, and shall be calculated by the following  
formula:  
F = S x N / W  
Where:  
S
N
Manufacturer's rated breaking strength of 1 rope.  
Number of ropes under load.  
Maximum static load on all ropes with the platform and  
its rated load at any point of its travel.  
W
(iv) Hoisting ropes shall be sized to conform with the required factor of safety, but  
in no case shall the size be less than 5/16 inch diameter.  
(v) Winding drums shall have at least 3 turns of rope remaining when the platform  
has landed at the lowest possible point of its travel.  
(vi) The lengthening or repairing of wire rope by the joining of 2 or more lengths is  
prohibited.  
(vii) The non-drum ends of the hoisting ropes shall be provided with individual  
shackle rods which will permit individual adjustment of rope lengths, if required.  
(viii) More than 2 reverse bends in each rope is prohibited.  
(21) "Rope tag data.”  
(i) A metal data tag shall be securely attached to 1 of the wire rope fastenings. This  
data tag shall bear the following wire rope data:  
(a) The diameter in inches.  
(b) Construction classification.  
(c) Whether non-preformed or preformed.  
(d) The grade of material used.  
(e) The manufacturer's rated breaking strength.  
(f) Name of the manufacturer of the rope.  
(g) The month and year the ropes were installed.  
(22) "Electrical wiring and equipment.”  
(i) All electrical equipment and wiring shall conform to the requirements of General  
Industry Safety Standard Part 39 “Design Safety Standards for Electrical Systems,"  
except as modified by ANSI A120.1 “Safety Requirement for Powered Platforms for  
Exterior Building Maintenance,” 1970 edition, as adopted in R 408.40509. For detail  
design specifications for electrical equipment, see Part 2 of ANSI A120.1, 1970 edition.  
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(ii) All motors and operation and control equipment shall be supplied from a single  
power source.  
(iii) The power supply for the powered platform shall be an independent circuit  
supplied through a fused disconnect switch.  
(iv) Electrical conductor parts of the power supply system shall be protected against  
accidental contact.  
(v) Electrical grounding shall be provided.  
(a) Provision for electrical grounding shall be included with the power-supply  
system.  
(b) Controller cabinets, motor frames, hoisting machines, the working platform, roof  
car and roof car track system, and noncurrent carrying parts of electrical equipment,  
where provided, shall be grounded.  
(c) The controller, where used, shall be so designed and installed that a single  
ground or short circuit will not prevent both the normal and final stopping device from  
stopping the working platform.  
(d) Means shall be provided on the roof car and working platform for grounding  
portable electric tools.  
(e) The working platform shall be grounded through a grounding connection in a  
traveling cable. Electrically powered tools utilized on the working platform shall be  
grounded.  
(vi) Electrical receptacles located on the roof or other exterior location shall be of a  
weatherproof type and shall be located so as not to be subject to contact with water or  
accumulated snow. The receptacles shall be grounded and the electric cable shall include  
a grounding conductor. The receptacle and plug shall be a type designed to avoid hazard  
to persons inserting or withdrawing the plug. Provision shall be made to prevent  
application of cable strain directly to the plug and receptacle.  
(vii) Electric runway conductor systems shall be of the type designed for use in  
exterior locations and shall be located so as not to be subject to contact with water or  
accumulated snow. The conductors, collectors, and disconnecting means shall conform to  
the same requirements as those for cranes and hoists in General Industry Safety Standard  
Part 39 “Design Safety Standards for Electrical Systems," as referenced in R 408.40509.  
A grounded conductor shall parallel the power conductors and be so connected that it  
cannot be opened by the disconnecting means. The system shall be designed to avoid  
hazard to persons in the area.  
(viii) Electrical protective devices and interlocks of the weatherproof type shall be  
provided.  
(ix) Where the installation includes a roof car, electric contact or contacts shall be  
provided and so connected that the operating devices for the working platform shall be  
operative only when the roof car is located and mechanically retained at an established  
operating point.  
(x) Where the powered platform includes a power-operated roof car, the operating  
device for the roof car shall be inoperative when the roof car is mechanically retained at  
an established operating point.  
(xi) An electric contact shall be provided and so connected that it will cause the  
down direction relay for vertical travel to open if the tension in the traveling cable  
exceeds safe limits.  
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(xii) An automatic overload device shall be provided to cut off the electrical power  
to the circuit in all hoisting motors for travel in the up direction, should the load applied  
to the hoisting ropes at either end of the working platform exceed 125 percent of its  
normal tension with rated load, as shown on the manufacturer's data plate on the working  
platform.  
(xiii) An automatic device shall be provided for each hoisting rope which will cut  
off the electrical power to the hoisting motor or motors in the down direction and apply  
the brakes if any hoisting rope becomes slack.  
(xiv) Upper and lower directional limit devices shall be provided to prevent the  
travel of the working platform beyond the normal upper and lower limits of travel.  
(xv) Operation of a directional limit device shall prevent further motion in the  
appropriate direction, if the normal limit of travel has been reached.  
(xvi) Directional limit devices, if driven from the hoisting machine by chains, tapes,  
or cables, shall incorporate a device to disconnect the electric power from the hoisting  
machine and apply both the primary and secondary brakes in the event of failure of the  
driving means.  
(xvii) Final terminal stopping devices of the working platform:  
(a) Final terminal stopping devices for the working platform shall be provided as a  
secondary means of preventing the working platform from over-traveling at the terminals.  
(b) The device shall be set to function as close to each terminal landing as practical,  
but in such a way that under normal operating conditions it will not function when the  
working platform is stopped by the normal terminal stopping device.  
(c) Operation of the final terminal stopping device shall open the potential relay for  
vertical travel, thereby disconnecting the electric power from the hoisting machine, and  
applying both the primary and secondary brakes.  
(d) The final terminal stopping device for the upper limit of travel shall be mounted  
so that it is operated directly by the motion of the working platform itself.  
(xviii) Emergency stop switches shall be provided in or adjacent to each operating  
device.  
(xix) Emergency stop switches shall comply with the following:  
(a) Have red operating buttons or handles.  
(b) Be conspicuously and permanently marked "Stop."  
(c) Be the manually opened and manually closed type.  
(d) Be positively opened with the opening not solely dependent on springs.  
(xx) The manual operation of an emergency stop switch associated with an operating  
device for the working platform shall open the potential relay for vertical travel, thereby  
disconnecting the electric power from the hoisting machine and applying both the  
primary and secondary brakes.  
(xxi) The manual operation of the emergency stop switch associated with the  
operating device for a power-driven roof car shall cause the electrical power to the  
traverse machine to be interrupted, and the traverse machine brake to apply.  
(23) "Requirements for emergency communications.”  
(i) Communication equipment shall be provided for each powered platform for use  
in an emergency.  
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(ii) Two-way communication shall be established between personnel on the roof and  
personnel on the stalled working platform before any emergency operation of the  
working platform is undertaken by personnel on the roof.  
(iii) The equipment shall permit 2-way voice communication between the working  
platform and include the following:  
(a) Designated personnel continuously available while the powered platform is in  
use; and  
(b) Designated personnel on roof-powered platforms, undertaking emergency  
operation of the working platform by means of the emergency operating device located  
near the hoisting machine.  
(iv) The emergency communication equipment shall be either of the following  
types:  
(a) Telephone connected to the central telephone exchange system.  
(b) Telephones on a limited system or an approved 2-way radio system, provided  
designated personnel are available to receive a message during the time the powered  
platform is in use.  
(D) "TYPE T POWERED PLATFORMS"  
(1) "Roof car." The requirements of paragraphs (c)(1) to (5) of this appendix apply  
to Type T powered platforms.  
(2) "Working platform." The requirements of paragraphs (c)(6) to (16) of this  
appendix apply to Type T powered platforms.  
(i) The working platform shall be suspended by at least 2 wire ropes.  
(ii) The maximum rated speed at which the working platform of self-powered  
platforms may be moved in a vertical direction shall not exceed 35 feet per minute.  
(3) "Hoisting equipment." The requirements of paragraphs (c)(17) and (18) of this  
appendix shall apply to Type T powered platforms.  
(4) "Brakes." Brakes requirements of paragraph (c)(19) of this appendix apply.  
(5) "Hoisting ropes and rope connections.”  
(i) Paragraph (c)(20)(i) to (vi) and (viii) of this appendix apply to type T powered  
platforms.  
(ii) Adjustable shackle rods in subparagraph (c)(20)(vii) of this appendix shall apply  
to Type T powered platforms if the working platform is suspended by more than 2 wire  
ropes.  
(6) "Electrical wiring and equipment.”  
(i) The requirements of paragraph (c)(22)(i) to (vi) of this appendix apply to Type T  
powered platforms. "Circuit protection limitation," "powered platform electrical service  
system," all operating services and control equipment shall comply with the  
specifications contained in Part 2, section 26, of ANSI A120.1 “Safety Requirement for  
Powered Platforms for Exterior Building Maintenance,” 1970 edition, as adopted in  
R 408.40509.  
(ii) For electrical protective devices the requirements of paragraph (c)(22)(i) to (viii)  
of this appendix apply to Type T powered platforms. Requirements for the "circuit  
potential limitation" shall be in accordance with the specifications contained in Part 2,  
section 26, of ANSI A120.1 “Safety Requirement for Powered Platforms for Exterior  
Building Maintenance,” 1970 edition, as adopted in R 408.40509.  
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(7) "Emergency communications." All the requirements of paragraph (c)(23) of this  
appendix apply to Type T powered platforms.  
History: 1992 AACS; 2008 AACS; 2016 AACS; 2018 AACS.  
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;