5.1 Exit routes: how many, how wide, how marked

1 The three words the standard uses

Subpart E splits an exit route into three parts, and the vocabulary matters because the requirements attach to different parts. The exit access is the portion that leads to an exit. The exit is the portion, generally separated by fire-resistant construction, that provides a protected way of travel. The exit discharge is the part that leads directly outside or to a street, walkway, refuge area, public way or open space with access to the outside — 1910.36(c)(1).

A warehouse's exit access is the aisle. That is why Part 1's aisle rules and this chapter are the same subject seen twice: the pallet in the aisle is a materials handling problem at 8 a.m. and an egress problem at any moment after that.

2 How many, how big

Two of those get violated routinely in warehouses. (d)(1) is broken by security: a door chained, bolted or fitted with a keyed lock at night because of theft. And (g)(2) and (g)(4) are broken by storage: a 44-inch corridor with pallets down one side is not a 44-inch exit access any more.

3 Free and unobstructed, in writing

1910.37(a)(3) is the paragraph to quote when somebody stages product in a corridor: "Exit routes must be free and unobstructed. No materials or equipment may be placed, either permanently or temporarily, within the exit route." Temporarily is in the text. There is no ten-minute allowance and no "we're moving it after this trailer."

The same section adds three more: (a)(1) exit routes kept free of explosive or highly flammable furnishings or decorations; (a)(2) routes arranged so employees do not have to travel toward a high hazard area unless effectively shielded from it; and (a)(4) safeguards designed to protect employees during an emergency — sprinkler systems, alarm systems, fire doors, exit lighting — kept in proper working order at all times.

Fire doors deserve a note of their own, because propping them is so common. A fire door wedged open is a safeguard that is not in working order under (a)(4), and 1910.36(a)(3) requires openings into an exit to be protected by a self-closing fire door that remains closed or closes automatically on the alarm.

4 Lighting, marking and the signs nobody checks

1910.37(b) is unusually specific, and it is the easiest thing in this chapter to audit with a walk and a ladder.

• (b)(1) — each exit route adequately lighted so an employee with normal vision can see along it.
• (b)(2) — each exit clearly visible and marked by a sign reading "Exit."
• (b)(4) — where the direction of travel is not immediately apparent, directional signs along the exit access; the line of sight to an exit sign must be clearly visible at all times.
• (b)(5) — each doorway or passage that could be mistaken for an exit marked "Not an Exit" or identified by its actual use.
• (b)(6) — each exit sign illuminated to a surface value of at least five foot-candles by a reliable light source, and distinctive in color; self-luminous or electroluminescent signs need a minimum luminance of 0.06 footlamberts.
• (b)(7) — the word "Exit" in plainly legible letters not less than 6 inches high, with principal strokes not less than 3/4 inch wide.

5 Travel distance, occupant load and where OSHA stops

Two questions come up in every warehouse discussion and OSHA does not answer either one numerically. How far may someone have to travel to reach an exit, and how many exits does an occupant load require? Subpart E points elsewhere for both: the notes to 1910.36(b) and (f) refer the reader to NFPA 101, the Life Safety Code, and the International Fire Code, incorporated by reference at 1910.6.

Those are paid consensus documents; this course names them and does not reproduce their tables. What it means practically is that your building's exit count, travel distances and occupant load came from the building code and the fire marshal, not from OSHA — and that a change in use (adding a mezzanine, converting an area to high-piled storage, building a pick module) can invalidate the original design. That is a conversation with the fire marshal, not something to work out from part 1910.

6 During construction and alterations

Warehouses expand while they operate, and 1910.37(d) covers exactly that. During new construction employees must not occupy a workplace until the required exit routes are complete and ready for use for the portion they occupy. During repairs or alterations, employees must not occupy the workplace unless the required exit routes are available and existing fire protections are maintained — or alternate protection providing an equivalent level of safety is furnished.

And 1910.37(d)(3): employees must not be exposed to hazards of flammable or explosive substances or equipment used during the work that go beyond normal permissible conditions, or that would impede exiting. A contractor's spray-applied fireproofing or a temporary hoarding across a corridor is squarely in that paragraph. The practical control is a written interim life safety plan for the duration of the project — temporary exit signage, alternate routes walked with the crews, and a daily check that the temporary route is still clear.