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 the Michigan occupational safety and health act, 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 6. FIRE EXITS  
GENERAL PROVISIONS  
R 408.10601 Scope.  
Rule 601. (1) These rules specify requirements for means of egress for employee use  
required by the advent of hazardous conditions such as fire, explosion, and natural  
disaster.  
(2) These rules apply to workplaces in general industry except mobile workplaces  
such as vehicles or vessels.  
(3) These rules cover the minimum requirements for exit routes that employers must  
provide in their workplace so that employees may evacuate the workplace safely during  
an emergency. These rules cover the minimum requirements for emergency action plans  
and fire prevention plans.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10602 Applicability.  
Rule 602. (1) This part covers new and existing construction. In various sections of  
this part there are special provisions for existing buildings differing from those for new  
construction. Where there are no specific provisions in this part for existing buildings,  
the requirements for new construction shall apply.  
(2) If a political subdivision of the state has fire safety standards in conflict with this  
part, the more restrictive provisions of either the political subdivision or this standard  
shall apply.  
History: 1979 AC.  
R 408.10603 Definitions; B to F.  
Rule 603. (1) "Breakaway door" means a door that is designed to slide in normal  
operation and which will swing open in any position when a maximum pressure of 50  
pounds is applied to the latch side of the door in an emergency.  
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(2) "Draw bolt" means a metal bar or rod in the mechanism of a lock that is thrown  
or withdrawn by turning the key or retracting a lever.  
(3) “Electroluminescent” means a light-emitting capacitor. Alternating current  
excites phosphor atoms when placed between the electrically conductive surfaces to  
produce light. This light source is typically contained inside the device.  
(4) "Fire area of a building" means that space contained within component structural  
parts that has a fire resistance sufficient to prevent the further spread of fire that  
originates therein.  
(5) "Fire door" means a fire-resistive door assembly, including the frame and  
hardware.  
(6) "Fire resistance" means the property of a material or assembly to withstand fire  
or give protection from it.  
(7) "Flammable" means subject to easy ignition and rapid flaming combustion.  
(8) "Floor area" or "gross area" means the floor area within the perimeter of the  
outside walls of a building, with no deductions for any of the following:  
(a) Hallways.  
(b) Stairs.  
(c) Closets.  
(d) Thickness of walls.  
(e) Columns.  
(f) Other features.  
(9) "Flush bolt" means a door bolt that is designed so that when applied it is flush  
with the face or edge of the door.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10604 Definitions; H to M.  
Rule 604. (1) "Hasp and staple" means a fastening device that consists of a slotted  
hinge plate and a loop (staple).  
(2) "Hazardous area" means an area of a building, or portion thereof, used for  
purposes that involve highly combustible, highly flammable, or explosive products or  
materials which are likely to burn with extreme rapidity or which may produce poisonous  
fumes or gases, including highly toxic or noxious acids, alkalines, or irritant hazards;  
which cause the division of material into fine particles or dust subject to explosion or  
spontaneous combustion; or which constitute a high fire hazard because of the form,  
character, or volume of the material used.  
(3) "Hazard of contents" means the relative danger of the start and spread of fire, the  
danger of smoke or gases generated, and the danger of explosion or other occurrence  
potentially endangering the lives and safety of employees in a building. Where certain  
features of a building are such as to involve a hazard greater than the hazard of the  
contents, the greater degree of hazard shall govern.  
(4) High hazard area” means an area inside a workplace in which operations  
include high hazard materials, processes, or contents.  
(5) "High hazard contents" means combustibles of a character or quantity that burn  
with extreme rapidity or from which extremely poisonous fumes or explosions are to be  
expected in the case of fire.  
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(6) "Horizontal exit" means a way of passage from a building to an area of refuge in  
another building on approximately the same level or a way of passage through or around  
a fire-resistant wall or fire-resistant partition to an area of refuge on approximately the  
same level in the same building which affords safety from fire or smoke in the area of  
escape and areas communicating therewith.  
(7) "Listed” means equipment that is listed if it is of a kind mentioned in a list that is  
published by a nationally recognized testing laboratory that makes periodic inspections of  
the production of such equipment and that states that such equipment meets nationally  
recognized standards or has been tested and found safe for use in a specified manner.  
(8) "Low hazard contents" means combustibles of such low combustibility that self-  
propagating fire cannot occur and that consequently the only probable danger will be  
from panic, fumes, smoke, or fire from some external source.  
(9) "Means of egress” also known as an “exit routemeans a continuous and  
unobstructed path of exit travel from any point within a workplace to a place of safety,  
including refuge areas. A means of egress includes both vertical and horizontal areas  
along the route of travel. A means of egress or an exit route consists of 3 separate parts  
and are defined as follows:  
(a) "Exit access" means that portion of a means of egress or an exit route which  
leads to an exit. An example of an exit access is a corridor on the 5th floor of an office  
building that leads to a 2-hour fire resistance-rated enclosed stairway.  
(b) "Exit" means that portion of a means of egress or an exit route that is separated  
from the area of a building from which escape is to be made by a wall, floor, door, or  
other means which provides the protected path necessary to proceed with reasonable  
safety to the exterior of the building. An example of an exit is a 2-hour fire resistance-  
rated enclosed stairway that leads from the 5th floor of an office building to the outside of  
the building.  
(c) "Exit discharge" means that portion of an exit route that leads directly outside or  
to a street, walkway, refuge area, public way, or open space with access to the outside.  
An example of an exit discharge is a door at the bottom of a 2-hour fire resistance-rated  
enclosed stairway that discharges to a place of safety outside the building.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10605 Definitions; N to S.  
Rule 605. (1) “Nationally recognized testing laboratory." See 29 C.F.R. §1910.7  
Definition and requirements for a nationally recognized testing laboratory,” as adopted  
in R 408.10606, for the definition.  
(2) "Noncombustible building" means a building that is constructed of materials that  
do not support fire.  
(3) “Occupant load” means the total number of persons that may occupy a  
workplace or portion of a workplace at any one time. The occupant load of a workplace is  
calculated by dividing the gross floor area of the workplace or portion of the workplace  
by the occupant load factor for that particular type of workplace occupancy. Information  
regarding the "Occupant load" is located in NFPA 101 “Life Safety Code,” 2009 edition  
and in the “International Fire Code” 2009 edition, as adopted in R 408.10606.  
Page 3  
(4) "Ordinary hazard contents" means combustibles that are liable to burn with  
moderate rapidity and to give off a considerable volume of smoke, but from which  
neither extremely poisonous fumes nor explosions are to be expected in case of fire.  
(5) “Refuge area” means either of the following:  
(a) A space along an exit route that is protected from the effects of fire by separation  
from other spaces within the building by a barrier with at least a 1-hour fire resistance-  
rating.  
(b) A floor with at least 2 spaces, separated from each other by smoke-resistant  
partitions, in a building protected throughout by an automatic sprinkler system that  
complies with General Industry Safety Standard Part 9 “Fixed Fire Equipment,” as  
referenced in R 408.10606.  
(6) "Self-closing" means equipped with an approved device which will ensure  
closing without manual assistance after having been opened.  
(7) "Sprinklered" means equipped with an approved automatic sprinkler system that  
is properly maintained.  
(8) "Street" means a public thoroughfare that is 30 or more feet in width, that has  
been dedicated or deeded to the public for public use, and that is accessible for use by a  
fire department in fighting fires. An enclosed space or tunnel, even though used for  
vehicular and pedestrian traffic, is not considered a street.  
(9) Self-luminous” means a light source that is illuminated by a self-contained  
power source, like tritium, and that operates independently from external power sources.  
Batteries are not acceptable self-contained power sources. The light source is typically  
contained inside the device.  
(10) "Surface bolt" means a locking bolt that is installed on the surface of a door.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10606 Adoption of standards by reference; access to MIOSHA rules.  
Rule 606. (1) The National Fire Protection Association NFPA 101 “Life Safety  
Code,” 2009 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 the following website: http://global.ihs.com, at a  
cost as of the time of adoption of these rules of $93.00.  
(2) The “International Fire Code” 2009 edition, is adopted by reference in these  
rules and is available from International Code Council, 500 New Jersey Avenue, NW, 6th  
floor, Washington, DC 20001, USA, telephone number: 1-800-786-4452, or via the  
internet at the following website: www.iccsafe.org, at a cost as of the time of adoption of  
these rules of $113.00.  
(3) The following federal Occupational Safety and Health Administration (OSHA)  
regulations are adopted by reference in these rules:  
(a) 29 CFR 1910.7 “Definition and requirements for a nationally recognized testing  
laboratory,as amended February 25, 2011.  
(b) 29 CFR 1910.165 “Employee alarm systems,as amended September 12, 1980.  
(4) The federal regulations adopted by reference in these rules are available from  
the United States Department of Labor, Occupational Safety and Health Administration  
website: www.osha.gov, at no charge, as of the time of adoption of these rules.  
Page 4  
(5) The standards adopted in these rules are 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.  
(6) Copies of the standards 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.  
(7) 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 the following 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 9. “Fixed Fire Equipment,” R 408.10901  
to R 408. 10999.  
History: 1979 AC; 1990 AACS; 2015 AACS; 2019 AACS.  
R 408.10607 Rescinded.  
History: 1954 ACS 62, Eff. May 18, 1970; rescinded 1954 ACS 79, Eff. May 16, 1974.  
R 408.10608 Notification of emergency escape procedures and routes;  
designation of evacuation assistants.  
Rule 608. (1) An employer shall assure that employees are informed of emergency  
escape procedures and emergency routes to approved means of egress.  
(2) An employer shall designate a sufficient number of persons to assist in the safe  
and orderly emergency evacuation of employees.  
History: 1990 AACS.  
R 408.10610 Rescinded.  
History: 1954 ACS 69, Eff. Nov. 15, 1971; rescinded 1954 ACS 79, Eff. May 16, 1974.  
R 408.10611 Design of buildings and structures.  
Rule 611. (1) The danger to employees must be minimized.  
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(2) A building or structure designed for human occupancy shall be provided with  
exits, as prescribed in this part, that permit prompt escape in case of fire or other  
emergency.  
(3) Exits and other safeguards shall be designed so that an employee's safety or  
preservation of life in case of fire or other emergency is not dependent solely on a single  
safeguard. Additional safeguards shall be provided for life safety in case any single  
safeguard is ineffective due to human or mechanical failure.  
(4) Exit routes shall be kept free of explosive or highly flammable furnishings or  
other decorations.  
(5) A building or structure shall be constructed, arranged, equipped, maintained, and  
operated to avoid undue danger to the lives and safety of the employees from fire, smoke,  
fumes, or panic during the period of time necessary for escape from the building or  
structure.  
(6) An employee alarm system must be operable. Employers shall install and  
maintain an operable employee alarm system that has a distinctive signal to warn  
employees of fire or other emergencies, unless employees can promptly see or smell a  
fire or other hazard in time to provide adequate warning to them. The employee alarm  
system must comply with General Industry Safety Standard Part 9 “Fixed Fire  
Equipment,” and 29 C.F.R. 1910.165 “Employee alarm systems” as adopted in  
R 408.10606.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10612 Occupancy of new buildings.  
Rule 612. During new construction, employees shall not occupy a workplace until  
the exit routes required by these rules are completed and ready for employee use for the  
portion of the workplace they occupy.  
History: 1979 AC; 2015 AACS.  
R 408.10613 Occupancy and use during repairs and alterations.  
Rule 613. (1) During repairs or alterations, employees shall not occupy a workplace  
unless the exit routes required by these rules are available and existing fire protections are  
maintained, or until alternate fire protection is furnished that provides an equivalent level  
of safety.  
(2) Employees shall not be exposed to hazards of flammable or explosive substances  
or equipment used during construction, repairs, or alterations, that are beyond the normal  
permissible conditions in the workplace, or that would impede exiting the workplace.  
History: 1979 AC; 2015 AACS.  
R 408.10614 Operating condition of protective equipment.  
Page 6  
Rule 614. A required exit, exit lighting, automatic sprinkler system, fire detection  
and alarm system, fire door, and other required items of fire protection shall be  
maintained in proper operating condition.  
History: 1979 AC.  
R 408.10615 Rescinded.  
History: 1954 ACS 62, Eff. May 18, 1970; rescinded 1954 ACS 79, Eff. May 16, 1974.  
R 408.10616 Rescinded.  
History: 1954 ACS 69, Eff. Nov. 15, 1971; rescinded 1954 ACS 79, Eff. May 16, 1974.  
R 408.10617 Rescinded.  
History: 1954 ACS 62, Eff. May 18, 1970; rescinded 1954 ACS 79, Eff. May 16, 1974.  
CLASSES OF OCCUPANCY AND HAZARD OF CONTENTS  
R 408.10621 Classes of occupancy.  
Rule 621. A building or part thereof shall be classified as follows:  
(a) A hotel, which includes a building, portion of a building, or group of buildings  
which is under the same management and in which there are more than 16 sleeping  
accommodations for hire that are primarily used by transients, whether designated as a  
hotel, apartment hotel, inn, club, or motel or by any other name.  
(b) Mercantile occupancy, which includes a store, market, and other room or  
building for the display and sale of merchandise. Examples of this occupancy are as  
follows:  
(i) Supermarkets.  
(ii) Department stores.  
(iii) Shopping centers.  
(iv) Drugstores.  
(v) Auction rooms.  
(c) Business occupancy, which means a place used for the transaction of business,  
other than that covered under mercantile occupancy, for the keeping of accounts and  
records and for similar purposes. Examples of this occupancy are as follows:  
(i) Doctors' and dentists' offices.  
(ii) City and township halls.  
(iii) Courthouses.  
(iv) Libraries.  
(v) Schools.  
(d) An industrial occupancy, which includes a factory that makes products of all  
kinds and a property devoted to operations such as processing, assembling, mixing,  
Page 7  
packaging, finishing or decorating, repairing, and similar operations. Examples of this  
group are as follows:  
(i) Laboratories.  
(ii) Dry cleaning plants.  
(iii) Power plants.  
(iv) Pumping stations.  
(v) Smokehouses.  
(vi) Laundries.  
(vii) Creameries.  
(viii) Gas plants.  
(ix) Refineries.  
(x) Sawmills.  
(e) A storage occupancy, which includes a building that is used primarily for the  
storage or sheltering of goods, merchandise, products, vehicles, or animals. Examples of  
this group are as follows:  
(i) Warehouses.  
(ii) Cold storage operations.  
(iii) Freight terminals.  
(iv) Truck and marine terminals.  
(v) Bulk oil storage.  
(vi) Parking garages.  
(vii) Hangars.  
(viii) Grain elevators.  
(ix) Barns.  
(x) Stables.  
(f) Miscellaneous occupancies, which means those buildings covered in the  
provisions of R 408.10691 to R 408.10697.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10622 Multiple and partial occupancies.  
Rule 622. (1) If 2 or more classes of occupancy occur in the same building so  
intermingled that separate safeguards are impracticable, the safeguard facilities shall be  
sufficient to meet the requirements for each individual area or section, as well as for the  
entire building.  
(2) If a minor portion of a building is used for any purpose incidental to the major  
occupancy and the minor occupancy does not incur any hazard to the remainder of the  
building, it shall be classified as part of the major occupancy.  
History: 1979 AC.  
R 408.10623 Employee emergency action plans.  
Rule 623. (1) An employer shall have an emergency action plan whenever required  
by a particular Michigan occupational safety and health act standard. The requirements in  
these rules apply to each such emergency action plan.  
Page 8  
(2) An emergency action plan shall be in writing, kept in the workplace, and  
available to employees for review. However, an employer with 10 or fewer employees  
may communicate the plan orally to employees.  
(3) An emergency action plan shall include at a minimum all of the following:  
(a) Procedures for reporting a fire or other emergency.  
(b) Procedures for emergency evacuation, including type of evacuation and exit  
route assignments.  
(c) Procedures to be followed by employees who remain to operate critical plant  
operations before they evacuate.  
(d) Procedures to account for all employees after evacuation.  
(e) Procedures to be followed by employees performing rescue or medical duties.  
(f) The name or job title of every employee who may be contacted by employees  
who need more information about the plan or an explanation of their duties under the  
plan.  
(4) An employer shall establish an employee alarm system that is in compliance  
with the provisions of General Industry Safety Standard Part 9 “Fixed Fire Equipment,”  
and 29 C.F.R. 1910.165 “Employee alarm systems” as adopted in R 408.10606. If the  
employee alarm system is used for alerting fire brigade members or for other purposes, a  
distinctive signal for each purpose shall be used.  
(5) An employer shall establish in the emergency action plan the types of evacuation  
to be used in emergency circumstances.  
(6) Before implementing the emergency action plan, an employer shall designate  
and train a sufficient number of persons to assist in the safe and orderly emergency  
evacuation of employees.  
(7) The employer shall review the plan, at the following times, with each employee  
to whom the plan applies:  
(a) When the plan is developed.  
(b) If an employee's responsibilities or designated actions under the plan change.  
(c) If the plan is changed.  
(8) An employer shall review, with each employee, upon initial assignment, those  
parts of the plan that the employee must know to protect the employee in an emergency.  
History: 1993 AACS; 2015 AACS.  
R 408.10624 Fire prevention plans.  
Rule 624. (1) An employer shall have a fire prevention plan whenever they are  
required by a particular Michigan occupational safety and health act standard. The  
requirements in these rules apply to each such fire prevention plan.  
(2) A fire prevention plan must be in writing, be kept in the workplace, and be made  
available to employees for review. However, an employer with 10 or fewer employees  
may communicate the plan orally to employees.  
(3) An employer shall control the accumulations of flammable and combustible  
waste materials and residues so that they do not contribute to a fire emergency. The  
control procedures shall be included in the written fire prevention plan.  
(4) An employer shall inform employees of the fire hazards of the materials and  
processes to which they are exposed.  
Page 9  
(5) An employer shall review, with each employee, upon initial assignment, those  
parts of the fire prevention plan that the employee must know to protect the employee in  
an emergency.  
(6) An employer shall regularly and properly maintain, according to established  
procedures, equipment and systems that are installed on heat-producing equipment to  
prevent the accidental ignition of combustible materials. The maintenance procedures  
shall be included in the written fire prevention plan.  
(7) Minimum elements of a fire prevention plan shall include all of the following  
information:  
(a) A list of all major fire hazards, proper handling and storage procedures for  
hazardous materials, potential ignition sources and their control, and the type of fire  
protection equipment necessary to control each major hazard.  
(b) Procedures to control accumulations of flammable and combustible waste  
materials.  
(c) Procedures for regular maintenance of safeguards installed on heat-producing  
equipment to prevent the accidental ignition of combustible materials.  
(d) The name or job title of employees responsible for maintaining equipment to  
prevent or control sources of ignition or fires.  
(e) The name or job title of employees responsible for the control of fuel source  
hazards.  
History: 1993 AACS; 2015 AACS.  
R 408.10625 Rescinded.  
History: 1954 ACS 62, Eff. May 18, 1970; rescinded 1954 ACS 79, Eff. May 16, 1974.  
R 408.10626 Rescinded.  
History: 1954 ACS 62, Eff. May 18, 1970; rescinded 1954 ACS 79, Eff. May 16, 1974.  
R 408.10627 Compliance with alternate exit-route codes.  
Rule 627. MIOSHA shall deem an employer demonstrating compliance with the  
exit-route provisions of the NFPA 101 “Life Safety Code,” 2009 edition or the exit-route  
provisions of the “International Fire Code” 2009 edition, as adopted in R 408.10606, to  
be in compliance with the corresponding requirements in these rules.  
History: 2015 AACS.  
MEANS OF EGRESS  
R 408.10631 Construction, maintenance, and changes.  
Page 10  
Rule 631. (1) The components of a means of egress including doors, stairs, ramps,  
passages, and signs shall be of substantial construction and shall be maintained in an  
operable condition.  
(2) An exit shall be not less than 28 inches (71.1 cm) wide at all points, except  
where specifically permitted elsewhere in this part. Where there is only 1 exit access  
leading to an exit or exit discharge, the width of the exit and exit discharge shall be at  
least equal to the width of the exit access.  
(3) The ceiling of an exit route shall be at least 7 feet 6 inches (2.3 m) high. Any  
projection from the ceiling shall not reach a point less than 6 feet 8 inches (2.0 m) from  
the floor.  
(4) The width of an exit route shall be sufficient to accommodate the maximum  
permitted occupant load of each floor served by the exit route.  
(5) Objects that project into the exit route shall not reduce the width of the exit route  
to less than the minimum width requirements for exit routes.  
(6) Exit routes must be kept free of explosive or highly flammable furnishings or  
other decorations.  
(7) A space formed with movable or folding partitions and occupied by more than  
20 persons shall have an approved means of egress.  
(8) An alteration, addition, or change of occupancy that would reduce means of  
egress below the requirements for a new building is prohibited.  
(9) Furnishings and decorations of an explosive or highly flammable character shall  
not be used in any occupancy.  
(10) Where fire retardant paints or solutions are used, they shall be renewed, as  
necessary to maintain their fire retardant properties.  
History: 1979 AC; 2015 AACS.  
R 408.10632 Obstructions.  
Rule 632. (1) An employer shall ensure that exit routes are free and unobstructed.  
No materials or equipment may be placed, either permanently or temporarily, within the  
exit route. The exit access must not go through a room that can be locked, such as a  
bathroom, to reach an exit or exit discharge, nor may it lead into a dead-end corridor.  
Stairs or a ramp must be provided where the exit route is not substantially level.  
(2) A lock, fastening device, or barrier must not be installed or used on a means of  
egress in a manner that will prevent or hinder free escape from the inside of a building.  
(3) Exit route doors must be free of any device or alarm that could restrict  
emergency use of the exit route if the device or alarm fails.  
(4) Devices such as turnstiles and gates must not be placed so as to obstruct a means  
of egress.  
(5) Combustible or flammable debris, waste, or other material, the burning of which  
would render hazardous egress from the building must not be placed, stored, or kept on,  
under, at the bottom of, or adjacent to a means of egress or elevator. Where a means of  
egress is being obstructed by the placement of movable objects, aisles must be marked,  
and railings or permanent barriers provided to protect the means of egress against  
encroachment.  
Page 11  
(6) Each exit route door must be free of decorations or signs that obscure the  
visibility of the exit route door. A mirror must not be placed on an exit door or be placed  
in or adjacent to an exit in a manner to confuse the direction of exit.  
History: 1979 AC; 2015 AACS; 2019 AACS.  
R 408.10633 Permissible exits and exit components.  
Rule 633. (1) Approved exits for all occupancies regulated by this part shall be  
restricted to the following permissible types: doors, inside or outside stairs, horizontal  
exits, ramps, escalators, and fire escapes for existing occupancies.  
(2) An exit shall consist only of approved components. An exit shall be constructed  
as an integral part of the building or permanently affixed thereto.  
(3) Stairs, landings, and other exit components shall be guarded against falls over  
open edges, and guards and handrails shall continue the full length of the guarded exit  
component.  
(4) An exit protected by separation from other parts of the building shall have the  
separating construction meet the following:  
(a) The separation shall have not less than a 1-hour fire-resistance rating when the  
exit connects 3 stories or less. This applies whether the stories connected are above or  
below the story at which the exit discharge is located.  
(b) The separation shall have not less than a 2-hour fire-resistance rating when the  
exit connects 4 or more stories, whether above or below the floor of discharge.  
(c) An opening into an exit must be protected by a self-closing fire door that remains  
closed or automatically closes in an emergency upon the sounding of a fire alarm or  
employee alarm system.  
(d) An opening in an exit enclosure shall be confined to that which is necessary for  
access to the enclosure from a normally occupied space and for egress from the  
enclosure.  
(5) Each exit route shall be a permanent part of the workplace.  
(6) Each fire door, including its frame and hardware, shall be listed or approved by a  
nationally recognized testing laboratory. For the definition of a "nationally recognized  
testing laboratory, see 29 C.F.R. §1910.7 “Definition and requirements for a nationally  
recognized testing laboratory,” as adopted in R 408.10606.  
History: 1979 AC; 2015 AACS.  
R 408.10634 Number of exits.  
Rule 634. (1) An employer shall ensure that there are an adequate number of exit  
routes.  
(2) Where the contents of a building are classified as high hazard, there shall be not  
less than 2 exits which are accessible in different directions. All doors shall swing in the  
direction of exit travel. Where floor areas are divided into rooms, there shall be not less  
than 2 ways of escape from every room, however small, except for toilet rooms that are  
not located in areas of high hazard classification.  
Page 12  
(3) The exit routes shall be located as far away as practical from each other so that if  
1 exit route is blocked by fire or smoke, employees can evacuate using the second exit  
route.  
(4) At least 2 exit routes shall be available in a workplace to permit prompt  
evacuation of employees and other building occupants during an emergency, except as  
allowed in subrule (6) of this rule.  
(5) More than 2 exit routes shall be available in a workplace if the number of  
employees, the size of the building, its occupancy, or the arrangement of the workplace is  
such that all employees would not be able to evacuate safely during an emergency.  
(6) A single exit route is permitted where the number of employees, the size of the  
building, its occupancy, or the arrangement of the workplace is such that all employees  
would be able to evacuate safely during an emergency.  
Note: For assistance in determining the number of exit routes necessary for your  
workplace, consult NFPA 101 “Life Safety Code,” 2009 edition or “International Fire  
Code” 2009 edition, as adopted in R 408.10606.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10635 Travel distance to exits.  
Rule 635. (1) The total number of exits in a building shall be sufficient so that  
the maximum travel distance from any occupied space to at least 1 exit shall not exceed  
the limits specified in R 408.10636.  
(2) The distance to an exit shall be measured along the center line of the natural  
and unobstructed path of travel.  
(3) In case of an open area, the distance to an exit shall be measured from the most  
remote point subject to occupancy. In case of an individual room subject to occupancy  
by not more than 6 persons, distance to an exit shall be measured from the doors of such  
room if the path of travel from any point in the room to the door does not exceed 50  
feet.  
(4) Where an open stairway is part of a path of travel to a required exit, the  
distance shall include the travel on the stairway, and the travel from the end of the  
stairway to reach an outside door or other exit, in addition to the distance to reach the  
stairway.  
(5) Where any part of an outside stair or other outside exit is within 15 feet  
horizontal distance of an unprotected building opening, the distance to an exit shall  
include the length of travel, to ground level, on the exit itself.  
(6) Exits and exit access shall be so arranged that there are no dead-end pockets  
or hallways whose depths exceed the limits specified for the individual occupancies in  
table 1.  
History: 1979 AC.  
R 408.10636 Maximum travel distance to exits.  
Rule. 636. Table 1 reads as follows:  
Page 13  
TABLE 1  
Maximum travel distance to  
exits  
Dead-end  
limits (in feet)  
(in feet)  
Type of occupancy  
Mercantile,  
Unsprinkler  
Sprinklered  
250  
ed  
ordinary  
150  
50  
hazard  
Mercantile, high hazard  
Business  
75  
75  
0
200  
200  
0
300  
250  
75  
50  
50  
0
Industrial  
Industrial, high hazard  
Storage, low and ordinary  
hazard  
200  
400  
100  
Storage, high hazard  
Hotels  
75  
100  
200  
0
100  
50  
Note: For miscellaneous structures, See R 408.10691 to R 408.10697  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10637 Rescinded.  
History: 1979 AC; 2015 AACS.  
R 408.10638 Rescinded.  
History: 1979 AC; 2015 AACS.  
R 408.10639 Capacity as affected by population.  
Rule 639. (1) The capacity of a means of egress from a building, floor, balcony, tier,  
or other occupied space shall be sufficient for the population thereof. The population for  
industrial and storage occupancies shall be based on the maximum number of employees  
or persons that may be in the space at any time as determined by actual count. All other  
types of occupancies shall be not less than the number computed in accordance with the  
provisions of table 2.  
(2) Mercantile occupancy in a single-story, noncombustible building with an  
approved, fully equipped automatic sprinkler system that is in compliance with General  
Page 14  
Industry Safety Standard Part 9 “Fixed Fire Equipment,” as referenced in R 408.10606,  
may increase the square footage requirement in table 2 by 100%.  
(3) The population of an occupancy shall be limited to the existing exit capacity of a  
building or space.  
(4) Where an exit serves more than 1 floor, only the population of each floor  
considered individually need be used in computing the capacity of the exit at that level, if  
the exit capacity is not decreased in the direction of exit travel. Where a means of egress  
from floors above and below converge at an intermediate level, the capacity of the exit  
from the point of convergency shall be not less than the combined capacity of the  
converging exits.  
(5) Table 2 reads as follows:  
TABLE 2  
Type of occupancy  
Square feet per person  
30  
Mercantile, street floor or sales  
basement  
Mercantile, other floors  
Mercantile, office  
Mercantile, storage  
Business  
60  
100  
300  
100  
200  
100  
Hotel  
Industrial  
Note: The computed population of an occupancy is obtained by dividing the total  
floor area of a building, floor, or fire area by the indicated square feet per person. Total  
floor area means the floor area within the perimeter of the outside walls of a building,  
with no deductions for any of the following:  
(a) Hallways.  
(b) Stairs.  
(c) Closets.  
(d) Thickness of walls.  
(e) Columns.  
(f) Other features.  
(6) The capacity of an exit route shall be adequate. Information regarding the  
"Occupant load" is located in NFPA 101 “Life Safety Code,” 2009 edition and in the  
“International Fire Code” 2009 edition, as adopted in R 408.10606.  
(7) Exit routes shall support the maximum permitted occupant load for each floor  
served.  
(8) The capacity of an exit route shall not decrease in the direction of exit route  
travel to the exit discharge.  
History: 1979 AC; 2015 AACS.  
Page 15  
R 408.10641 Exit access and discharge.  
Rule 641. (1) An exit access must not be through a room subject to locking.  
(2) An exit access must be so arranged that it will not be necessary to travel through  
any area of high hazard occupancy to reach the nearest exit.  
(3) The minimum width of an exit access must be at least equal to the required width  
of the exit to which it leads, but not less than 34 inches. The headroom clearance must be  
not less than 6 feet 8 inches from the floor.  
(4) An exit discharge must discharge directly outside or to a street, walkway, refuge  
area, public way, or to a yard, court, or other open space with access to the outside.  
(5) Stairs and other exits must be arranged to make clear the direction of egress to  
the street. Where an exit stairs continues beyond the floor of discharge, it must be  
interrupted at the floor of discharge by a partition, door, or other effective means.  
(6) Exit access by the way of an exterior balcony, porch, gallery, or roof must be in  
compliance with all of the following:  
(a) Be kept free from accumulations of snow and ice.  
(b) Be a permanent direct route without obstructions, such as railings, gates, barriers,  
or other objects, that might divide the space into sections or rooms. Furniture or other  
movable objects must not block the path of travel.  
(c) Have no dead ends in excess of 20 feet.  
(d) Comply with this standard as to requirements for width and arrangement.  
(7) The street, walkway, refuge area, public way, or open space to which an exit  
discharge leads must be large enough to accommodate the building occupants likely to  
use the exit route.  
(8) An exit door must be unlocked.  
(9) An outdoor exit route is permitted.  
(10) The outdoor exit route must have all of the following:  
(a) Guardrails to protect unenclosed sides if a fall hazard exists.  
(b) Be covered if snow or ice is likely to accumulate along the route, unless the  
employer can demonstrate that any snow or ice accumulation will be removed before it  
presents a slipping hazard.  
(c) Be reasonably straight and have smooth, solid, substantially level walkways.  
(d) Not have a dead-end that is longer than 20 feet (6.2 m).  
(11) An exit access must be so arranged that employees will not have to travel  
toward a high hazard area, unless the path of travel is effectively shielded from the high  
hazard area by suitable partitions or other physical barriers.  
History: 1979 AC; 2015 AACS; 2019 AACS.  
DOORS AND STAIRS  
R 408.10643 Doors; general provisions.  
Rule 643. (1) A door assembly, including the doorway, frame, door, and necessary  
hardware, may be used as a component in a means of egress when it conforms to the  
requirements of this part. As such, the assembly is designated as an exit door.  
Page 16  
(2) A single leaf of an exit door shall be not less than 28 inches nor more than 48  
inches in width.  
(3) Where a door or gate opens directly on a stairway, a platform shall be provided,  
and the swing of the door or gate shall not reduce the floor area leading to the stairs to a  
width less than 20 inches.  
History: 1979 AC; 2015 AACS.  
R 408.10644 Door swing.  
Rule 644. (1) A side-hinged exit door shall be used. The force required to fully open  
any door in the means of egress shall not be more than 5 pounds applied to the latch side  
of the door. The door shall swing with exit travel when serving an area of high hazard  
occupancy or a building, floor, or area with a population of more than 50 persons.  
(2) If 1 or more approved exits are provided and the travel distance requires  
additional exits, a mechanically aided sliding door may be used to exit to the outside of a  
building constructed before May 15, 1970, under the following conditions:  
(a) The occupancy shall be classified as a low or ordinary storage hazard or an  
ordinary mercantile hazard.  
(b) The mechanical aid to the door shall allow the door to be opened quickly and  
easily by 1 person.  
(c) The mechanical aid of the door shall not be rendered inoperative by fire or the  
lack of maintenance.  
(3) An exit door that gives access to a stairway shall swing in the direction of exit  
travel, shall not block stairs or landings during its swing, and shall not interfere with the  
full use of the stairway when open.  
(4) An exit door at the foot of stairs from upper floors or at the head of stairs from  
basements shall swing with exit travel.  
(5) A screen door or storm door that is part of a required exit shall not swing against  
the direction of exit travel in any case where doors are required to swing with exit travel.  
(6) A side-hinged door shall be used to connect any room to an exit route.  
(7) The door that connects any room to an exit route shall swing out in the direction  
of exit travel if the room is designed to be occupied by more than 50 people or if the  
room is a high hazard area; for example, it contains contents that are likely to burn with  
extreme rapidity or explode.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10645 Locks, fastening devices, and closing mechanism.  
Rule 645. (1) Employees shall be able to open an exit route door from the inside at  
all times without keys, tools, or special knowledge. A device such as a panic bar that  
locks only from the outside is permitted on exit discharge doors.  
(2) A latch or other fastening device on an exit door shall be provided with a knob,  
handle, panic bar, or other simple type of releasing device. Slide bolts, hasps, hooks and  
eyes, and similar types of locking devices that are difficult to open against door pressure  
shall not be installed or used.  
Page 17  
(3) A fire door to a stair enclosure or horizontal exit shall be provided with a reliable  
self-closing mechanism and shall not, at any time, be secured in the open position.  
(4) An exit route door may be locked from the inside only in mental, penal, or  
correctional facilities and then only if supervisory personnel are continuously on duty and  
the employer has a plan to remove occupants from the facility during an emergency.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10646 Power operated doors.  
Rule 646. An exit door, wholly or partly power operated, shall be so designed that  
in case of power failure it can be manually operated. A power operated door shall not  
be counted as a required exit unless it swings with the exit travel.  
History: 1979 AC.  
R 408.10647 Revolving doors.  
Rule 647. (1) A revolving door shall be considered an approved exit door only if all  
of the following conditions are satisfied:  
(a) The door shall be installed before the prohibition listed in subrule (2) of this rule.  
(b) The number of revolving doors used as exit doors shall not be more than the  
number of swinging doors used as exit doors within 20 feet thereof.  
(c) A revolving door without an adjacent swinging door may serve as an exit for a  
street floor elevator lobby if no stairway or door from other parts of the building  
discharges through the lobby and the lobby has no occupancy other than as a means of  
travel between elevators and the street.  
(d) A revolving door shall be equipped with means to prevent its rotation at more  
than 12 1/2 revolutions per minute.  
(e) A revolving door shall not be used at the foot of stairs from upper floors or at the  
head of stairs from the basement or other lower floors.  
(f) A revolving door credited as an exit door shall have a rated capacity of 1/2 unit  
of exit width.  
(2) A revolving door that is installed after June 15, 1990, shall not be considered an  
approved exit door.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10651 Stairs.  
Rule 651. (1) Stairs serving as a required exit shall comply with the requirements  
of this part as to construction specifications and details, and of table 3.  
**** INSERT MISSING TABLE OR CHART  
MANUSCRIPT ****  
-
SEE ORIGINAL  
Page 18  
(2) A variation in the width of tread or height of risers in any flight shall not exceed  
3/16 inch.  
(3) A stair and a platform or landing used in connection therewith, in a building 4  
stories or more in height, shall be of noncombustible construction throughout,  
except for handrails.  
(4) A stair, platform, landing, balcony, and stair hallway floor shall be designed to  
carry a load of 100 pounds per square foot, or a concentrated load of 300 pounds so  
located as to produce maximum stress conditions.  
(5) Where the material of stair treads and landings is such as to involve danger  
of slipping, nonslip material shall be provided on the tread surface.  
(6) Stairways and intermediate landings shall continue with no decrease in width  
along the direction of exit travel.  
(7) Monumental stairs, either inside or outside, may be accepted as required exits  
if all requirements for exit stairs are complied with, except that curved stairs may be  
accepted with a radius of 25 feet or more at the inner edges.  
History: 1979 AC.  
HORIZONTAL EXITS, RAMPS, AND ESCALATORS  
R 408.10661 Horizontal exits.  
Rule 661. (1) A fire area or area of refuge with a horizontal exit shall have, in  
addition to the horizontal exit or exits, at least 1 means of egress leading to the outside, or  
have access to an adjacent fire area containing an outside means of egress.  
(2) Where either side of a horizontal exit is occupied, the doors used in connection  
with the horizontal exit shall be unlocked.  
(3) The floor area on either side of a horizontal exit shall be sufficient to hold the  
occupants of both floor areas allowing not less than 3 square feet clear floor area per  
person.  
(4) Where a horizontal exit serves areas on both sides of a wall, there shall be  
adjacent openings with swinging doors at each, opening in opposite directions, with signs  
on each side of the wall or partition indicating as the exit door which swings with the  
travel from that side; or other approved arrangements providing doors always swinging  
with any possible exit travel.  
History: 1979 AC; 2015 AACS.  
R 408.10664 Ramps.  
Rule 664. (1) A ramp may be a component in a means of egress when it conforms to  
the requirements of this part. A ramp which is constructed after June 15, 1990, and which  
Page 19  
is less than the minimum measurements prescribed in this rule shall not be considered as  
an approved part of a means of egress.  
(2) A ramp and the platforms and landings associated therewith shall be designed for  
not less than 100 pounds per square foot live load.  
(3) The slope of a ramp shall not vary between landings. A landing shall be level  
and the changes in direction of travel, if any, shall be made only at landings.  
(4) A ramp in a building that is more than 3 stories in height shall be made of  
noncombustible construction. A ramp floor and landings shall be solid and without  
perforations.  
(5) A ramp shall have a nonslip surface.  
(6) A ramp shall have a minimum width of 44 inches and a maximum slope of 1  
inch in 12 inches.  
History: 1979 AC; 1990 AACS; 2015 AACS.  
R 408.10667 Escalators.  
Rule 667. An escalator, to be considered a component of means of egress, shall be  
fully enclosed above the ground floor and equipped with fire doors containing fusible  
links to protect the escalator area against the passage of flame, smoke, and gases in the  
event of fire. An escalator being operated in the direction contrary to normal exit travel  
shall not be considered a means of egress.  
History: 1979 AC.  
FIRE ESCAPES  
R 408.10671 Fire escape stairs.  
Rule 671. (1) Fire escape stairs may be used as a required exit only in existing  
buildings. Fire escape stairs shall not constitute more than 50% of the required exit  
capacity. Fire escape stairs shall not constitute any part of the required exits for a new  
building.  
(2) Fire escape stair dimensions shall be in accordance with table 4.  
Page 20  
TABLE 4  
22 inches clear between  
rails  
Minimum Width  
Minimum horizontal dimension of a landing or  
platform  
22 inches  
Maximum rise  
9 inches  
Minimum tread, exclusive of nosing  
Spiral winders  
9 inches  
Not permitted  
12 feet  
Maximum height between landings  
(3) Fire escape stairs shall have walls or approved guards, and handrails on both  
sides.  
History: 1979 AC; 2015 AACS.  
R 408.10672 Stair construction and load.  
Rule 672. (1) Iron, steel, concrete, or other approved noncombustible material  
shall be used for the construction of fire escape stairs, balconies, railings, and other  
features appurtenant thereto.  
(2) Balconies and stairs shall be designed to carry a load of 100 pounds per square  
foot, or a concentrated load of 300 pounds so located as to produce maximum stress  
conditions.  
History: 1979 AC.  
R 408.10673 Exposure to fire escape stairs.  
Rule 673. Fire escape stairs shall be so arranged that they will be subject to exposure  
by the smallest possible number of window and door openings. Every opening, any  
portion of which is within the following limits, shall be completely protected by approved  
fire doors or metal frame wired glass windows, as follows:  
(a) A horizontal opening if within 15 feet of a balcony, platform or stairway  
constituting a part of the escape proper. This does not apply to a platform or walkway  
leading from the same floor to the escape proper. Protection need not extend around a  
right angle corner (outside angle 270 degrees) of the building.  
(b) An opening below if within 3 stories or 36 feet of a balcony, platform, walkway  
or stairway constituting a part of the escape proper, or within 2 stories or 24 feet of a  
platform or walkway leading from any story to the escape proper.  
(c) An opening above if within 10 feet of a balcony, platform or walkway, as  
measured vertically, or from any stair treads, as measured vertically from the face of the  
outside riser.  
(d) An opening on a top story. Protection for wall openings is not required where  
stairs do not lead to the roof.  
Page 21  
History: 1979 AC; 2015 AACS.  
R 408.10674 Access to fire escape stairs.  
Rule 674. (1) Access to fire escape stairs shall be by doors or casement windows  
whose minimum dimensions are 24 inches by 6 feet 6 inches, or by double hung  
windows 30 by 36 inches clear opening. Double hung windows shall be so  
counterbalanced and maintained that they can be readily opened.  
(2) Insert screens, if any, on any type of opening giving access to fire escape stairs  
shall be of types that may be readily opened or pushed out. Storm sash shall not be used  
on a window providing access to fire escape stairs.  
(3) Access to fire escape stairs through windows with sills more than 12 inches  
above the inside floor level shall be provided with permanent access steps leading to  
the access window. The outside balcony shall not be more than 18 inches below the sill.  
History: 1979 AC.  
R 408.10675 Swinging stairs.  
Rule 675. (1) A swinging stair section shall not be used for a fire escape stairs,  
except where termination is over a sidewalk, alley, or driveway.  
(2) A swinging stair section shall not be located over doors, over the path of travel  
from another exit, nor be in any location where there are obstructions.  
(3) The width of a swinging stair section shall be at least equal to that of the stairs  
above and the pitch shall not be steeper than that of the stairs above.  
(4) A counterweight shall be provided for a swinging stair section and this shall be  
of the type balancing about a pivot, no cables being used. Counter-balancing shall be  
such that a weight of 150 pounds 1 step from pivot will not start swinging section, and a  
weight of 150 pounds, 1/4 of the length of the swinging stairs from the pivot, will  
positively cause the stairs to swing down.  
(5) A latch or other device shall not be installed or used to lock a swinging stair  
section in the up position.  
History: 1979 AC; 2015 AACS.  
R 408.10677 Ladders.  
Rule 677. No form of ladder shall be used as a fire escape except that a ladder  
conforming to General Industry Safety and Health Standard Part 2. “Walking-Working  
Surfaces,” as referenced in R 408.10606, may be used to provide a means of escape from  
a boiler room, storage elevator, or tower, as permitted for special miscellaneous  
occupancies, elevated platforms around machinery, or similar spaces subject to routine  
simultaneous occupancy by not more than 3 persons.  
History: 1979 AC; 2015 AACS; 2019 AACS.  
Page 22  
R 408.10679 Rescinded.  
History: 1979 AC; 1998-2000 AACS.  
ILLUMINATION AND MARKING  
R 408.10680 Lighting.  
Rule 680. (1) Lighting and marking shall be adequate and appropriate.  
(2) Each exit route shall be adequately lighted so that an employee with normal  
vision can see along the exit route.  
History: 2015 AACS.  
R 408.10681 Artificial lighting.  
Rule 681. (1) A means of egress shall be illuminated by artificial lighting at  
places and for periods of time required to maintain the illumination to values not less  
than 1.0 footcandles measured at the floor. Illumination shall be so arranged that the  
failure of any single lighting unit, such as the burning out of an electric bulb, will not  
leave the area in darkness.  
(2) Artificial lighting shall be from a source of reasonable reliability, such as  
a public utility service. A battery operated electric light or any type of portable lamp or  
lantern shall not be used for primary exit illumination. Luminescent, fluorescent,  
or reflective material shall not be used as a substitute for required illumination.  
History: 1979 AC.  
R 408.10682 Emergency illumination.  
Rule 682. In a building with natural lighting subject to occupancy by more than  
300 persons, and in a building for which no natural lighting is provided and subject to  
occupancy by more than 100 persons, approved emergency lighting facilities shall be  
provided for a means of egress so arranged that required exit illumination will be  
maintained for a period of at least 1/2 hour in the event of failure of normal lighting of  
the building. Emergency lighting facilities shall be automatic, and there shall be no  
appreciable period of interruption during the change-over from the normal lighting of the  
building.  
History: 1979 AC.  
R 408.10685 Signs.  
Page 23  
Rule 685. (1) A means of egress to an exit not immediately apparent from any point  
in an occupancy shall be marked by directional signs. Additionally, the line-of-sight to an  
exit sign shall be clearly visible at all times.  
(2) A door, passage, or stairway, which is neither an exit nor an exit access, and  
which is so located or arranged as to be likely mistaken for an exit, shall be identified by  
a sign reading "NOT AN EXIT" or similar designation, or be identified by a sign  
indicating its actual use or character.  
(3) A sign shall designate an exit and shall be located and be of such size and color  
and design as to be readily visible and identifiable from the distance of travel for that  
particular occupancy.  
(4) Each exit must be clearly visible and marked by a sign reading "EXIT."  
History: 1979 AC; 2015 AACS.  
R 408.10686 Sign illumination and letter size.  
Rule 686. (1) An exit sign shall be illuminated to a surface value of at least 5 foot-  
candles (54 lux) by a reliable light source and be distinctive in color. Self-luminous or  
electroluminescent signs that have a minimum luminance surface value of at least .06  
foot lamberts (0.21 cd/m2) are permitted.  
(2) An exit sign shall have the word "EXIT" in plainly legible letters not less than 6  
inches (15.2 cm) high, with the principal strokes of the letters in the word "EXIT" not  
less than 3/4 of an inch (1.9 cm) wide.  
(3) An internally illuminated exit sign shall be provided where the reduction of  
normal illumination is permitted and less than 5 footcandles would appear on the exit  
sign.  
History: 1979 AC; 2015 AACS.  
MISCELLANEOUS OCCUPANCIES  
R 408.10691 Vehicles.  
Rule 691. A house trailer or similar vehicle, railroad car, street car, truck, or bus  
from which the wheels have been removed and a permanent-type foundation provided, or  
otherwise fixed so that it is no longer mobile, is considered a building and is subject to  
the requirements of this part.  
History: 1979 AC.  
R 408.10692 Vessels.  
Rule 692. A ship, barge, or other vessel permanently moored or aground and  
occupied for purposes other than navigation is subject to the requirements of this  
part.  
Page 24  
History: 1979 AC.  
R 408.10693 Open buildings.  
Rule 693. An open building includes all operations conducted in the open air where  
equipment is in the open with platforms used for necessary access, sometimes with  
roofs or canopies to provide shelter, but without walls as distinguished from an enclosed  
building. An open building shall have exit facilities providing at least 1 means of escape  
from any point subject to employee occupancy, such means of escape affording safety  
from fire or smoke therefrom, explosion or release of fumes.  
History: 1979 AC.  
R 408.10694 Aircraft hangars.  
Rule 694. (1) An exit from an aircraft storage or servicing area shall be provided at  
intervals of not more than 150 feet on all exterior walls of the aircraft hangar. A  
minimum of 2 exits shall serve each aircraft storage or servicing area. Horizontal exits  
through interior walls shall be provided at intervals of not more than 100 feet. Dwarf or  
"smash" doors in doors accommodating aircraft may be used to comply with these  
requirements.  
(2) An exit from a mezzanine floor in an aircraft storage or servicing area shall be  
so arranged that the maximum travel to reach the nearest exit from any point on the  
mezzanine shall not exceed 75 feet.  
History: 1979 AC.  
R 408.10695 Storage elevators for combustible commodities.  
Rule 695. (1) In a storage elevator for combustible commodities there must be at  
least 1 stairway from the basement to the first floor and from the first floor to the top  
floor of the working house that is enclosed in a dust-tight, non-combustible shaft.  
(2) A non-combustible door of the self-closing type must be provided at each floor  
landing.  
(3) An exterior stair or basket ladder-type fire escape, must be provided from the  
roof of the working house to ground level or to the roof of an adjoining annex with access  
from all floors above the first, in compliance with General Industry Safety and Health  
Standard Part 2. “Walking-Working Surfaces,” as referenced in R 408.10606.  
(4) An exterior stair or basket ladder-type fire escape, must be provided from the  
roof of each storage annex to ground level, in compliance with General Industry Safety  
and Health Standard Part 2. “Walking-Working Surfaces,” as referenced in R 408.10606.  
(5) A fire escape ladder must be provided adjacent to a manlift for the up and down  
sides.  
(6) A storage elevator must have an opening that leads to a fire escape ladder from  
each floor or work level.  
(7) Storage elevators for combustible commodities that exist before April 30, 1974,  
do not need to comply with the provisions of subrules (1) and (2) of this rule.  
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History: 1979 AC; 1990 AACS; 2015 AACS; 2019 AACS.  
R 408.10696 Towers.  
Rule 696. (1) A tower occupied for purposes such as observation or signaling, either  
an independent structure or on top of a building, shall be permitted with a single stairway  
or ramp exit if all of the following conditions are met:  
(a) The tower is of such size as not to be subject to occupancy by more than 25  
persons on any 1 floor level.  
(b) The tower is subject only to occupancy by persons capable of descending the  
stairway and is not used for living or sleeping purposes.  
(c) The construction is fire-resistive, non-combustible, or heavy timber, with no  
quick-burning interior finish. There must be no combustible materials in, under, or in the  
immediate vicinity of the tower, except as necessary to perform the requirements of  
occupancy.  
(2) Stairs must conform to the requirements of this standard, except that for existing  
towers fire escape type stairs may be used in compliance with General Industry Safety  
and Health Standard Part 2. “Walking-Working Surfaces,” as referenced in R 408.10606.  
(3) A tower, such as a forest fire observation tower and a railroad signal tower  
designed for occupancy by not more than 3 persons employed therein, need not be  
constructed of fire-resistive, non-combustible material and may be served by ladders  
instead of stairs in compliance with General Industry Safety and Health Standard Part 2.  
“Walking-Working Surfaces,” as referenced in R 408.10606.  
History: 1979 AC; 2015 AACS; 2019 AACS.  
R 408.10697 Piers and water-surrounded buildings.  
Rule 697. (1) A pier used for any purpose other than for mooring of vessels and  
handling of cargo shall be provided with a means of egress from any building thereon  
to the pier and from the pier to the mainland appropriate to the character of the  
occupancy of the pier.  
(2) A building, such as a lighthouse, surrounded by water shall have a sufficient  
area of ground, as on an island or fire-resistive platform, to provide an adequate area of  
refuge from a fire in the building.  
History: 1979 AC.  
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