Emergency Lighting and Exit Sign Requirements for Commercial Buildings

Important Compliance Note

This guide is for product selection and planning. It is not legal, engineering, or code approval advice. Requirements can vary by jurisdiction, building use, construction date, occupancy load, renovation scope, and local amendments. Always confirm final requirements with the adopted building code, fire code, electrical code, and your AHJ.

What Counts as an Exit Route?

An exit route is the full path people use to leave a building and reach a place of safety. OSHA 1910.34 describes an exit route as a continuous and unobstructed path from any point in the workplace to a place of safety. OSHA also breaks the route into three parts: exit access, exit, and exit discharge.

In plain English:

• Exit access is the path that leads to an exit. This might be a room, aisle, hallway, or corridor.
• The exit is the protected portion of the route, such as an enclosed stairway or protected passage.
• Exit discharge is the part that leads outside or to a public way, walkway, refuge area, or other safe discharge area.

That matters because exit signs and emergency lights are not only about the door at the end of a hall. They are about the route people must follow to get out.

For example, a warehouse aisle may need emergency lighting along the path to the exit access. A hallway turn may need a directional exit sign. A stair enclosure may need emergency illumination. The exterior discharge area may need lighting so people are not led out into darkness.

Which Commercial Buildings Need Emergency Lighting and Exit Signs?

Many commercial and public-use buildings need exit signs, emergency lighting, or both. Common examples include:

• Office buildings
• Retail stores
• Restaurants and hospitality spaces
• Warehouses and industrial facilities
• Schools, churches, and assembly spaces
• Medical and care facilities
• Hotels and multifamily common areas
• Parking structures and exterior egress paths

The rules that apply may come from several places at once. OSHA covers workplace exit route requirements. Local building and fire codes often adopt or reference model codes and standards. Electrical installation may involve the National Electrical Code. Product listings often reference standards such as UL 924 for emergency lighting and power equipment.

The practical takeaway: do not choose fixtures only by appearance. Choose them by the egress path, environment, power design, and inspection needs.

Exit Sign Requirements to Check

Exit signs identify exits and point people toward the nearest safe route. A compliant exit sign plan usually has to answer five questions.

1. Is every required exit clearly marked?

OSHA 1910.37 requires each exit to be clearly visible and marked by a sign reading "Exit." If an exit route door could be hidden, visually confusing, or mistaken for another door, the sign plan needs to make the route obvious.

For buyers, that means checking whether you need:

• A standard wall-mounted exit sign above a door
• A ceiling-mounted exit sign visible from a hallway
• An end-mounted sign visible from both directions
• A double-face sign where people approach from two directions
• A directional arrow when the route turns or the exit is not obvious

2. Is the direction of travel obvious?

If people cannot immediately tell which way to go, directional signs are typically needed. OSHA states that when the direction of travel to the exit or exit discharge is not immediately apparent, signs must indicate the direction to the nearest exit and exit discharge. The line of sight to an exit sign must also remain clearly visible.

This is where many buildings fail in practice. A sign over a final exit door may not be enough if a person standing at the end of a corridor cannot see that door. Turns, intersections, long corridors, storage racks, partial walls, and tenant improvements can all create blind spots.

3. Does the sign need arrows?

Use arrows when the sign is not directly over the exit or when it is guiding people through the route. Many exit signs include removable chevrons or knockout arrows. During planning, decide the arrow direction before ordering or installation.

Typical arrow use cases:

• Corridor turns
• T-intersections
• A sign mounted before the actual exit door
• Large open spaces where the nearest exit is not obvious
• Exit access paths around shelving, equipment, or partitions

4. Is the sign illuminated and legible?

OSHA includes requirements for illuminated exit signs, including minimum surface illumination for many signs and minimum letter dimensions. In practice, buyers should select signs intended for commercial exit marking and confirm that the product is appropriate for the code path and installation.

For common electrically powered signs, the most common choice is an LED exit sign with battery backup. For places where electrical wiring is difficult, a tritium exit sign may be considered, but tritium signs have special regulatory and disposal responsibilities.

5. Red or green exit sign?

Red exit signs are common in many U.S. jurisdictions, while green signs are used in others and are common internationally. Some local codes or project specifications may require one color. Do not assume the color is a preference decision. Check the local code, project drawings, and AHJ expectations before mixing colors in the same building.

Emergency Lighting Requirements to Check

Emergency lighting helps people see the path of egress when normal lighting is interrupted. It is different from an exit sign. An exit sign identifies the route. Emergency lighting illuminates the route.

1. Exit routes must be adequately lighted

OSHA requires each exit route to be adequately lighted so an employee with normal vision can see along the exit route. OSHA also requires safeguards such as exit lighting to be in proper working order at all times.

For buyers, this means old fixtures with dead batteries, dim heads, missing lamps, or failed test buttons are not just a maintenance nuisance. They can become a safety and inspection problem.

2. Emergency lights need a backup power plan

Emergency lighting can be powered in several ways:

• Self-contained battery emergency light units
• Exit sign emergency light combo units
• Remote heads powered by a battery unit with remote capacity
• Emergency lighting inverters or central battery systems
• Generator-backed emergency systems

Self-contained units are common because they are straightforward to install and replace. They include the lamps, battery, charger, and test function in one fixture. Larger buildings may use central systems, remote heads, or inverter-backed lighting, depending on the design.

3. The common 90-minute benchmark

Many building and life safety code paths use a 90-minute emergency operation benchmark for egress illumination. Treat that as a planning expectation, not a universal promise. The final runtime requirement depends on the adopted local code and the equipment used.

When comparing fixtures, look for product data about battery backup and emergency runtime. Do not assume every battery-backup product is appropriate for every egress application. For emergency lighting and power equipment, UL 924 is the key standard category to understand. UL describes the standard as applying to emergency lighting and power equipment such as exit signs, emergency luminaires, unit equipment, central battery banks, inverters, and emergency lighting control devices.

4. Illumination is about the path, not just the fixture

A two-head emergency light can be adjusted, but it still has limits. Mounting height, corridor length, fixture spacing, head aiming, wall color, obstacles, and open-area geometry all affect coverage.

Common planning areas include:

• Corridors and hallways
• Exit access aisles
• Stairs and landings
• Changes in direction
• Doors along the egress route
• Exit discharge areas outside the building
• Electrical rooms, mechanical rooms, and service spaces where required
• Warehouse aisles and large open areas

For complex layouts, photometric planning or an electrician's layout review may be needed.

Where to Place Exit Signs and Emergency Lights

The best way to plan placement is to walk the building like a person evacuating it.

Start at the farthest occupied point. Follow the route to the nearest exit. Ask these questions:

• Can I see an exit sign from here?
• If not, is there a directional sign telling me where to go?
• When I reach a turn or intersection, is the next direction obvious?
• Are stairs, ramps, landings, and doorways illuminated?
• Does the route stay visible if normal power fails?
• After I exit, is the discharge path safely illuminated?
• Are signs blocked by shelving, decorations, open doors, equipment, or tenant improvements?

Typical exit sign locations

Exit signs are commonly installed:

• Above required exit doors
• At corridor turns where the exit is not visible
• At intersections along the egress path
• In large rooms where the exit direction may not be obvious
• At stair doors or exit passage doors
• Where a double-face sign is needed for visibility from two directions

Typical emergency light locations

Emergency lights are commonly installed:

• Along corridors
• Near exits and exit access doors
• In stairways and landings
• At changes in direction
• Near changes in floor level
• In larger open areas that need egress path illumination
• Near exterior exit discharge areas

The goal is not to place a fixture at random intervals. The goal is to make the route usable in an emergency.

How to Choose the Right Fixture Type

Different spaces need different equipment. Use this table as a first-pass planning tool.

Fixture type	Best fit	Planning notes
LED exit sign	Standard indoor exit marking	Confirm red or green lettering, face count, mounting style, arrow needs, and battery backup.
Emergency light	Hallways, rooms, and egress paths needing illumination	Check head output, mounting height, battery runtime, self-test options, and environment rating.
Exit sign emergency light combo	Doorways needing both exit marking and emergency illumination	Good for compact installations, but confirm head coverage is enough for the route.
Remote emergency light heads	Extended corridors, large rooms, or areas beyond a base unit	Requires a compatible remote-capable unit and capacity planning.
Wet-location emergency light	Damp, outdoor, washdown, or exposed areas	Use protected housings where moisture or weather exposure is expected.
Tritium exit sign	Locations where wiring is difficult or unavailable	No electricity required, but regulated use and disposal apply.
Steel or vandal-resistant fixture	Schools, gyms, public areas, industrial spaces	Better fit when impact, tampering, or abuse is a concern.
Self-testing fixture	Facilities that want easier routine maintenance tracking	Helpful where maintenance teams manage many fixtures.

If you are replacing existing fixtures, match the old unit's core requirements first: voltage, mounting, face count, arrow direction, battery backup, environment rating, remote capacity, and housing type.

If you are planning new work, begin with the egress route, not the product catalog.

When to Use Combo Units

Exit sign emergency light combo units combine an illuminated exit sign with adjustable emergency light heads. They are useful when the area around an exit door needs both sign visibility and emergency illumination.

Good combo-unit applications include:

• Small commercial corridors
• Retail back-of-house exits
• Office exit doors
• Tenant improvement projects
• Replacement projects where a combined fixture already exists

Combo units are not always enough for long corridors, tall warehouses, stairways, or complex routes. In those cases, separate emergency lights, remote emergency lights, or additional fixtures may be needed.

Wet, Damp, Outdoor, and Harsh Locations

Environment rating matters. A basic indoor thermoplastic unit may not be right for exterior doors, parking structures, food service washdown areas, industrial spaces, or locations exposed to moisture.

Consider protected or specialty fixtures for:

• Exterior exit discharge areas
• Covered outdoor walkways
• Parking garages
• Warehouses with dust or moisture
• Washdown areas
• Cold storage areas
• Industrial spaces with impact risk

Use wet-location emergency lights when the application calls for fixtures built for wet or exposed environments. For exit marking in harsher areas, check whether a wet-location exit sign or wet-location combo unit is a better fit.

Tritium Exit Signs Need Special Handling

Tritium exit signs are self-luminous. They do not need electricity or batteries, which can make them useful where wiring is difficult. But they contain tritium gas and are regulated differently from standard LED signs.

The U.S. Nuclear Regulatory Commission explains that facilities using tritium exit signs are generally licensed device users and must follow regulatory requirements. The NRC also states that tritium exit signs must not be disposed of as normal trash. Unwanted signs must be transferred to a specific licensee, such as a manufacturer, distributor, licensed radioactive waste broker, or licensed low-level radioactive waste disposal facility. See the NRC tritium EXIT sign backgrounder for details.

Use tritium signs only when the project calls for them and someone is prepared to manage the ownership, transfer, and disposal responsibilities. For replacement or disposal planning, see tritium exit signs and tritium recycle disposal.

ADA and Tactile Exit Signage

Illuminated exit signs and tactile exit signs are related, but they are not the same thing.

The ADA 2010 Standards for Accessible Design include requirements for signs, raised characters, Braille, visual contrast, and mounting location in certain applications. For example, tactile signs have their own height and placement rules. These requirements can apply alongside illuminated exit sign requirements from building, fire, and workplace rules.

When planning a commercial project, do not assume one illuminated sign solves every signage requirement. Check whether tactile exit signage is required at exit doors, exit passageways, exit stairways, areas of refuge, or other locations under the applicable accessibility rules and local code.

Testing and Maintenance

Emergency lights and exit signs are not "install and forget" products. Batteries age. Lamps fail. LED boards dim or stop working. Chargers fail. Signs get blocked. Arrows get punched out in the wrong direction. Tenants add shelving, displays, or partitions that change line of sight.

Build a maintenance routine around these checks:

• Press the test button and confirm emergency heads turn on.
• Confirm exit signs remain illuminated.
• Check that battery indicators and charger status look normal.
• Confirm signs are visible from the required approach path.
• Make sure arrows point the correct direction.
• Check for cracked lenses, damaged housings, missing faceplates, or loose mounts.
• Clean dirt, dust, or paint overspray from signs and lenses.
• Record inspection dates, failures, repairs, and replacements.
• Replace batteries or fixtures when runtime or output is no longer reliable.

If a fixture fails a test, do not wait until the next inspection cycle. Replace the battery, lamp, board, or fixture based on the product design and maintenance history.

Common Mistakes to Avoid

Blocking the sign

Exit signs must stay visible. Pallets, displays, decorations, conduit, hanging signs, open doors, and new partitions can all create visibility problems.

Forgetting directional arrows

A sign with no arrow may be clear when installed above an exit door. It may be confusing when installed in a corridor before a turn.

Using indoor fixtures outside

Exterior exit discharge areas and damp spaces need fixtures suited to the environment. Use wet-location or protected equipment when required.

Assuming combo units cover everything

Combo units are useful, but their heads may not cover long corridors, stairs, or large rooms by themselves.

Ignoring remote capacity

Remote heads must be matched to a compatible base unit with enough capacity. Do not add remote heads just because the wiring is convenient.

Replacing a fixture without checking voltage and mounting

Confirm voltage, mounting style, face count, arrows, battery backup, environment rating, and housing requirements before ordering.

Treating code as one national rule

There is no single one-sentence rule that covers every commercial building. OSHA, adopted building code, fire code, electrical code, accessibility rules, and local amendments can all matter.

Quick Buyer Checklist

Before ordering, collect this information:

• Building type and space use
• Existing fixture photos
• Voltage
• Mounting style: wall, ceiling, end, recessed, or pendant
• Sign face count: single-face or double-face
• Letter color: red or green
• Arrow direction
• Indoor, damp, wet, cold, or hazardous environment
• Need for self-testing or remote heads
• Battery backup or central system requirements
• AHJ or project specification notes

For help matching fixtures to an existing building, request a quote or contact Unlimited Lights with photos, quantities, and project requirements.

FAQ

Are exit signs required in every commercial building?

Not every room needs its own exit sign, but many commercial buildings need exit signs at required exits and along exit routes where direction is not obvious. Requirements depend on occupancy, layout, local code, and AHJ interpretation.

Do emergency lights need battery backup?

Many self-contained emergency lights include battery backup so they can operate when normal power fails. Other projects may use inverters, central battery systems, generators, or other emergency power designs. Confirm the required power source with the project code path.

How long should emergency lights stay on?

Many code paths use a 90-minute emergency operation benchmark for egress illumination, but the final requirement depends on the adopted local code and the equipment design. Check the product data and the AHJ requirement before buying.

Can I use one combo unit instead of a separate exit sign and emergency light?

Sometimes. A combo unit can be a good fit when the same area needs exit marking and emergency illumination. It may not be enough for long corridors, stairways, warehouses, or complex paths that need additional emergency light coverage.

Are red or green exit signs required?

It depends on the jurisdiction and project specification. Red is common in many U.S. buildings, but green is required or preferred in some areas and applications. Confirm with local code and the AHJ before standardizing a project.

Where should emergency lights be installed?

Emergency lights are commonly used along corridors, stairs, landings, changes in direction, exit access paths, and exit discharge areas. The layout should illuminate the path people actually use to leave the building.

Are tritium exit signs legal?

Tritium exit signs can be used in many facilities, but they are regulated and require proper handling, transfer, and disposal. They should not be thrown away as normal trash.

Who approves the final layout?

The final authority is usually the local AHJ, such as the fire marshal, building inspector, or other code official. Electricians, engineers, architects, and facility managers may all help plan the system, but the AHJ determines acceptance for the project.

Final Takeaway

Emergency lighting and exit signs are part of a building's life safety system. The right plan starts with the exit route, not the fixture. Mark the exits clearly, illuminate the path, choose products that match the environment, and keep the equipment tested and maintained.

When you are ready to compare products, start with emergency lights, exit signs, and exit sign emergency light combo units. For projects with moisture exposure, remote heads, tritium signs, or replacement complexity, Unlimited Lights can help narrow the options before you order.

Related Reading

• How to Choose Exit Signs
• How to Choose Emergency Lights
• Exit Sign and Emergency Light Combo Units
• Tritium Exit Signs
• Emergency Light Testing and Maintenance Guide