Exit Sign Requirements: OSHA Specifications Compared (2026 Guide)

What are the OSHA requirements for exit signs?

Short answer: There are two different specifications, and which one applies depends on whether the worksite is general industry or construction. 29 CFR 1910.37(b) requires the word "Exit" in legible letters at least 6 inches high with principal strokes at least ¾ inch wide, illuminated to at least 5 foot-candles by a reliable light source, or 0.06 footlamberts minimum luminance if self-luminous or electroluminescent. 29 CFR 1926.200(d) uses the same 6-inch and ¾-inch dimensions but mandates red letters on a white field and says nothing about illumination. A third route exists: 1910.35 deems compliance with the exit-route provisions of NFPA 101 (2009) or the International Fire Code (2009) to satisfy the OSHA sections.

Published August 27, 2026

Exit signage is one of the few places in OSHA's standards where general industry and construction genuinely diverge on the specification of the same object, and the divergence runs in the direction most people would not guess. Construction is more prescriptive about the appearance of the sign; general industry is more prescriptive about how it is lit and about the surrounding route. A multi-employer site with a general contractor and a client's operations staff can have both applying at once, to signs mounted twenty feet apart.

This guide is a specification sheet. It sets the two standards side by side line by line, lists the four route-marking duties people forget because they are not about the sign itself, and walks a mixed-occupancy audit. It sits under our OSHA safety sign requirements hub, which covers the sign classes and colours generally.

Why this matters.
Exit signage is read exactly once by each person who needs it, under smoke, alarm noise and crowd pressure, by people who have never consciously looked at it before. Every other sign in a building gets a second chance. This one does not. That is why the standard specifies stroke width rather than just letter height — a thin 6-inch letter disappears at distance and in haze — and why the illumination duty sits in the same paragraph group as the marking duty. A sign that is correct on the drawing and dark at 2 a.m. has failed the only test that counts.

The two specifications, side by side

The colour finding people get backwards

Ask a room of safety professionals what colour an exit sign has to be and almost everyone answers red. In construction they are right — 1926.200(d) says red letters on a white field, and there is nothing to argue about. In general industry they are wrong: 1910.37(b)(6) asks only that the sign be distinctive in colour. That is why green running-man exit signs, standard through most of the world and increasingly common in US buildings designed by international firms, are not an OSHA violation in a general-industry workplace.

The practical caveat matters as much as the finding. Local building and fire codes frequently do specify colour, and they apply independently of OSHA. A green pictogram sign can be simultaneously acceptable to 1910.37 and unacceptable to the authority having jurisdiction. The correct answer to "can we use green exit signs?" is therefore: OSHA does not stop you in general industry, your fire marshal might, and consistency within a building matters more than which colour you land on.

The third route: NFPA 101 and the International Fire Code

Most discussion of exit signs stops at 1910.37 and never reaches the section immediately before it. 29 CFR 1910.35 provides that OSHA will deem an employer demonstrating compliance with the exit-route provisions of NFPA 101, Life Safety Code, 2009 edition, or the exit-route provisions of the International Fire Code, 2009 edition, to be in compliance with the corresponding requirements in 1910.34, 1910.36 and 1910.37.

This is genuinely useful and under-used. A building already designed, inspected and maintained to NFPA 101 — which describes a majority of institutional, healthcare, educational and large commercial occupancies in the United States — does not need a parallel OSHA-specific exit-sign programme. It needs documentation that the exit-route provisions of the named code are actually being met.

Two cautions before relying on it. First, the deeming provision names the 2009 editions specifically; a building maintained to a later NFPA 101 edition is almost certainly meeting or exceeding the 2009 requirements, but the compliance argument should be made deliberately rather than assumed. Second, the deeming runs to the exit-route provisions of those codes and to the corresponding OSHA sections — it is not a blanket substitution of a fire code for the OSHA standards generally.

NFPA 101's exit-sign requirements are more detailed than OSHA's on several points that OSHA leaves open, notably viewing distance, directional indicators, and the treatment of photoluminescent signs, which have to be charged by a specified minimum illumination level to perform. A facility choosing this route inherits those details along with the deemed compliance.

The four duties that are not about the sign

Most exit-signage findings are not "the letters were too small." They are about the space around the sign, and all four sit inside the same paragraph as the marking requirement.

• Adequate lighting along the whole route — 1910.37(b)(1). Not just at the sign. The test is whether an employee with normal vision can see along the exit route. Storage corridors and back-of-house passages with a single failed fitting fail this routinely.
• Nothing may obscure the exit door — 1910.37(b)(3). Decorations, furnishings and signage that conceal the door's visibility are the finding. Seasonal decoration in retail and healthcare is the classic recurring instance.
• Directional signs where the way is not obvious, with clear sightlines — 1910.37(b)(4). This is a design question answered by walking the route from the far corner of every room, not from the corridor.
• "Not an Exit" on doors that could be mistaken for one — 1910.37(b)(5). Electrical rooms, storage, mechanical spaces and freezers on an exit corridor. The standard accepts a sign stating the actual use — "Storage," "Electrical Room" — as an alternative to the words "Not an Exit," which is usually the better signal because it is informative rather than merely negative.

The "Not an Exit" duty is the one that pays for the walk. In a fire, a person moving fast down an unfamiliar corridor will try the first door they reach. An unmarked walk-in cooler on an exit access is a trap, and it is a trap that costs a $9 sign to remove.

Illumination, batteries and the maintenance duty nobody schedules

The 5 foot-candle figure at 1910.37(b)(6) is a surface value on the sign itself, delivered by a reliable light source. Two failure modes follow directly from those two words.

The first is measurement. Five foot-candles is not a large amount of light, but it is measured at the sign face, and a sign lit only by ambient corridor lighting frequently misses it — particularly after a relamping that changed the beam pattern, or in a corridor whose lighting has been dimmed for energy savings. A light meter held at the sign face settles the question in seconds and is worth doing after any lighting change.

The second is reliability, which in practice means the battery. Self-contained emergency units and combination exit/emergency fixtures carry batteries with a finite service life, and the failure is silent: the sign stays lit on building power and goes dark in the event it exists for. The standard's requirement for a reliable source is what makes the monthly function test and the annual duration test more than housekeeping. Facilities that log those tests alongside extinguisher inspections catch failures; facilities that leave them to whoever notices a dark sign do not.

Self-luminous signs — tritium units — and electroluminescent signs are explicitly permitted at a minimum luminance of 0.06 footlamberts. They need no power and no battery, which makes them attractive in unheated, remote or hard-to-wire locations, and tritium units decay predictably over a rated life measured in years. Photoluminescent signs are a different technology with a different failure mode: they must be charged by ambient light, so they fail in exactly the storerooms and stairwells where the lights are normally off.

Worked example: auditing a mixed general-industry and construction site

A manufacturing plant is running production while a contractor builds a 12,000 sq ft addition through a temporary corridor cut into the existing wall. Operations staff work under Part 1910; the contractor's crews work under Part 1926; the temporary corridor is used by both. Here is an audit sequence that produces defensible findings rather than an argument about which standard applies.

1. Draw the boundary before inspecting anything. Mark on the floor plan which areas are the employer's operations, which are the construction work area, and which are shared. Signage in the shared corridor should be specified to the stricter reading — red on white, 6-inch letters, ¾-inch strokes, illuminated to 5 foot-candles — because that set satisfies both standards at once and removes the jurisdictional argument entirely.
2. Measure a sample of existing signs rather than trusting the catalogue. Letter height and stroke width are quick to check with a rule. Undersized legends turn up most often on older combination units and on custom signs made on site, and stroke width fails more often than height because thin modern typefaces look correct until measured.
3. Meter the illumination at the sign face, not in the corridor. Take readings at the sign in the lighting condition that will exist at the worst hour — night shift, weekend, or with the corridor on reduced lighting. Record the readings; an undocumented "looked fine" is not an audit result.
4. Walk every route from the far corner of every occupied room. Stand where a person actually starts, not in the corridor. Where the direction to the nearest exit is not immediately apparent from that position, a directional sign is required, and sightlines to it must be clear of ductwork, temporary partitions and stacked material.
5. Identify every door on an exit access that is not an exit. Electrical rooms, mechanical spaces, storage, the compressor room, the construction lay-down door. Mark each with its actual use or with "Not an Exit." This is normally the largest single group of findings and the cheapest to close.
6. Check the exit doors themselves for obstruction and for what is hanging on them. Notices, schedules, seasonal decoration and contractor postings accumulate on exit doors and are a finding under 1910.37(b)(3) whatever their content.
7. Test the emergency lighting and battery-backed exit units, and log it. Press-to-test on every unit, with a duration test on the schedule the manufacturer specifies. A dead battery discovered in an audit is a closed finding; a dead battery discovered during an evacuation is an incident.
8. Re-walk after every temporary partition moves. On an active construction interface the exit routes change with the work, which means the audit is not an annual event. Tie the re-walk to the contractor's phasing plan so it happens on schedule rather than on memory, and fold the result into the site's emergency action plan.

Frequently asked questions about OSHA exit sign requirements

What size do exit sign letters have to be?

At least 6 inches (15.2 cm) high with principal strokes at least three-quarters of an inch (1.9 cm) wide. Both 1910.37(b)(7) for general industry and 1926.200(d) for construction use the same two dimensions, so this is one point where the standards agree exactly. Stroke width is the requirement more often missed, because a thin typeface can meet the height and fail the stroke.

Do OSHA exit signs have to be red?

In construction, yes — 1926.200(d) requires legible red letters on a white field. In general industry, no: 1910.37(b)(6) requires only that the sign be distinctive in colour, so green pictogram exit signs are acceptable to OSHA in a general-industry workplace. Local building and fire codes may still specify colour, and they apply independently.

How bright does an exit sign have to be?

Under 1910.37(b)(6), at least 5 foot-candles (54 lux) at the sign surface from a reliable light source. Self-luminous or electroluminescent signs are permitted instead if they maintain a minimum luminance of at least 0.06 footlamberts (0.21 cd/m²). The 5 foot-candle value is measured at the sign face, not in the corridor.

Does OSHA require illuminated exit signs?

OSHA requires that the sign be illuminated to the stated level by a reliable source, which in practice means an internally lit sign or a sign lit by a dedicated fixture. A sign relying only on general corridor lighting can comply if it actually achieves 5 foot-candles at the face and that lighting is reliable, but it usually fails the first time the corridor lighting is changed or dimmed.

What is the difference between 1910.37 and 1926.200 for exit signs?

They share the 6-inch letter height and three-quarter-inch stroke width. 1926.200(d) additionally mandates red letters on a white field but says nothing about illumination. 1910.37(b) leaves colour open while requiring 5 foot-candles of illumination or 0.06 footlamberts of self-luminance, and adds route lighting, directional signs, "Not an Exit" marking, and a prohibition on decorations obscuring exit doors.

Can we comply with NFPA 101 instead of the OSHA exit sign rules?

Yes, within limits. 29 CFR 1910.35 deems an employer demonstrating compliance with the exit-route provisions of NFPA 101, Life Safety Code, 2009 edition, or the International Fire Code, 2009 edition, to comply with the corresponding requirements in 1910.34, 1910.36 and 1910.37. The deeming is specific to those named editions and to the exit-route provisions, so the argument should be documented rather than assumed.

What does "Not an Exit" have to be posted on?

Any door, passage or stairway that could reasonably be mistaken for an exit — typically electrical and mechanical rooms, storage, closets and coolers opening onto an exit access. Under 1910.37(b)(5) the marking may read "Not an Exit" or may identify the actual use of the space, and naming the actual use is usually the more helpful of the two.

Are directional exit signs required?

They are required under 1910.37(b)(4) where the direction of travel to the nearest exit or exit discharge is not immediately apparent, and the sightline to any exit sign must be kept unobstructed. Whether the direction is "immediately apparent" is judged from where people actually are, which is why the audit walk starts in the far corner of each room rather than in the corridor.

Do exit signs need battery backup?

The standard requires a reliable light source rather than naming a technology. In practice that means either battery backup, an emergency circuit, or a self-luminous sign that needs no power at all. Whichever is chosen, the reliability requirement is what makes periodic function and duration testing part of compliance rather than optional maintenance.

Are photoluminescent exit signs OSHA compliant?

They can be, but they carry a condition the other technologies do not: they store ambient light and must be charged to perform. A photoluminescent sign in a space whose lights are normally switched off — a storeroom, a rarely used stairwell — will not deliver its rated luminance when needed. NFPA 101 addresses this by specifying the illumination that must be maintained on the sign; OSHA's text does not, which puts the burden on the specifier to verify the charging condition.

How often should exit signs and emergency lighting be tested?

OSHA's exit-route standards do not set a test interval. The intervals in general use come from NFPA 101 and from equipment manufacturers — typically a monthly function test and an annual full-duration test for battery units. Because 1910.35 makes NFPA 101 compliance a route to satisfying the OSHA sections, adopting those intervals is the cleanest way to evidence the "reliable light source" requirement.

Do small workplaces need exit signs?

The duty in 1910.37(b)(2) attaches to exits, not to building size: each exit must be conspicuously marked. A single-room workplace where the only exit is plainly visible from everywhere in the room is a different case from a small suite with a corridor, a back door and a storage room. If a person could hesitate about which door leads out, the signage duty is live.

Does a temporary construction corridor need exit signage?

Yes. Exit routes through temporary construction remain exit routes, and 1926.200(d) applies to the signs that mark them. Because temporary corridors change as the work phases, the signage has to be re-walked whenever partitions move rather than checked once at the start of the project.

Can an exit sign be mounted above the door on the corridor side only?

The requirement is that each exit be conspicuously marked and that sightlines to exit signs remain unobstructed. In a corridor where people approach from both directions, a single-face sign visible from only one side leaves the other approach unmarked. Double-face or two signs is the usual answer, decided by walking both approaches rather than by reading the specification.

Who enforces exit sign requirements — OSHA or the fire marshal?

Both, under different authority. OSHA enforces 1910.37 and 1926.200 as workplace safety standards; the authority having jurisdiction enforces the building and fire codes, which are frequently more prescriptive about colour, viewing distance and mounting. A sign can satisfy one and not the other, and the practical specification is the stricter of the two.

Does OSHA require exit route diagrams or evacuation maps?

Not as such. The exit-route standards require marking and lighting rather than posted maps. Evacuation diagrams are required or expected under many fire codes and in specific occupancies, and they are a normal element of an emergency action plan under 1910.38 for employers required to have one. Treat the map as an emergency-planning duty rather than a signage duty.

Further reading on this site

• OSHA safety sign requirements — the hub: the three sign classes, colours, tags and the ANSI edition table.
• OSHA vs ANSI safety signs — the two compliance routes for facility signage, and how to write a defensible specification.
• OSHA emergency action plan requirements — the plan the exit routes exist to serve, and what has to be in it.
• Floor marking colour code standards — keeping the exit access clear, and which floor markings are actually required.
• Fire extinguisher placement requirements — travel distance, mounting and access along the same routes.
• Fire extinguisher inspection guide — the inspection cadence to attach exit and emergency lighting tests to.
• What is OSHA 29 CFR 1910.157? — the portable extinguisher standard, including identification and accessibility.
• Danger vs warning vs caution signs — signal-word selection for the hazard signage alongside the exit route.