Michigan has adopted general industry rules for exit routes that are stricter than federal rules. The stricter rules are related to exit route capacity, design specifications (e.g., doors, stairs, ramps, escalators, illumination, and marking), distance to exits, number of exits, obstructions, safeguards, and temporary rooms.
There are additional rules not covered in this topic for:
- Doors and stairs (MAC r. 408.10643 to 408.10651)
- Horizontal exits, ramps, and escalators (MAC r. 408.10661 to 408.10667)
- Fire escapes (MAC r. 408.10671 to 408.10679)
- Illumination and marking (MAC r. 408.10681 to 408.10686)
- Miscellaneous occupancies (e.g., vehicles, vessels, open buildings, aircraft hangars, storage elevators for combustible commodities, towers, and piers and water-surrounded buildings) (MAC r. 408.10691 to 408.10697).
The Michigan Department of Labor and Economic Growth/Occupational Safety and Health Administration (MIOSHA) administers and enforces workplace safety and health standards for private and public sector workplaces in the state.
MAC r. 408.10637 to 408.10639
General requirements (MAC r. 408.10637). Where a building is equipped with exits so located as to satisfy travel distance requirements for the occupancy and hazard of contents classifications but has an exit deficiency due to its population density, additional exit capacity must be provided to satisfy the requirements of these rules.
The capacity of an exit route must be measured in units of width of 22 inches (in.). Fractions of a unit must not be counted, except that 12 in. added to one or more full units must be counted as one-half a unit of exit width. A 40-in. door may be rated as 2 units for existing ...