Exit Signs and Emergency Lighting: What Inspectors Look For

Egress lighting is the part of a job an inspector looks at first and a contractor prices last. The rules are not complicated, but they are specific, and getting them wrong is one of the few lighting mistakes that fails an inspection outright.

The two numbers that drive everything

Requirement	The rule
Duration	90 minutes of illumination after loss of normal power. This is why every emergency fixture carries a battery sized to it.
Light level	Average of 1 foot candle along the egress path at floor level, with no point below 0.1 fc. At the end of 90 minutes it may have decayed to an average of 0.6 fc and a minimum of 0.06 fc.
Uniformity	Generally no more than 40 to 1 maximum to minimum along the path. Bright pools with dark gaps between them do not pass.
Transfer	Illumination has to come on automatically and immediately on loss of normal power. No manual intervention.

That 1 foot candle average is lower than people expect and the 0.1 minimum is what actually catches layouts out. A long corridor lit by two units at the ends will hit the average and fail the minimum in the middle.

Where it is required

• The egress path. Corridors, aisles, passageways and stairways that lead to an exit.
• Stairways, including landings and each change of direction. Stairs are where a failure hurts most and inspectors know it.
• Exit discharge. The path outside the door until you reach a public way. This is the one most often forgotten on a retrofit.
• Large open areas where occupants must travel to reach an exit.
• Windowless rooms above a certain occupant load, and assembly spaces.
• Electrical and generator rooms serving the emergency system.

Exit signs

An exit sign is required at every exit door and anywhere the way out is not immediately obvious, with directional signs so that no point along the path is further than roughly 100 feet from a visible sign. Signs are illuminated at all times and stay illuminated on backup power for the same 90 minutes.

Doors that are not exits but could be mistaken for one may need to be marked accordingly, which is a detail that comes up more in older buildings with odd layouts.

Fixture choices

Type	Use it for
Exit sign	Marking the door. Red or green depending on local adoption, so check before you order a pallet.
Combination exit and emergency	The efficient answer at a door that also needs path illumination. One box, one circuit, one device to test.
Emergency unit, twin head	Corridors, stairs and exit discharge. Aimable heads let you cover the path rather than the wall.
Fixture with integral battery backup	A normal panel, troffer or high bay that drops to a reduced output on power loss. Keeps the ceiling clean and often cheaper than separate units where the layout allows.
Wet location or cold weather rated	Exit discharge, unheated stairwells, parking structures. A standard indoor unit outdoors will fail, and the battery is the first thing to go in the cold.

Testing, and the records that get asked for

Interval	Test
Monthly	A functional test of at least 30 seconds. Confirms the unit transfers to battery and the lamps light.
Annually	A full 90 minute discharge test. Confirms the battery still holds for the required duration.
Always	Written records of both, kept and available for inspection.

Self diagnostic units earn their money

A self testing unit runs its own monthly and annual tests and shows a fault with an LED, so the monthly walk becomes a look rather than a press. On a building with fifty or more units, the labor saved in the first year usually covers the price difference, and it removes the far more expensive risk of a building with no test records at all.

Self testing does not remove the requirement to keep records, it just makes them far easier to produce.

What actually gets flagged

• Nothing outside the exit door. The path to the public way counts and is routinely missed on retrofits.
• Dead batteries. Batteries have a service life of a few years. On an older building, assume a proportion of them are already gone and check before you quote.
• No test records. The fixtures can be perfect and the building still gets written up.
• Signs blocked or removed. Racking, ductwork, signage and tenant fitouts get installed in front of exit signs constantly.
• Emergency units on a switched circuit. They have to sense loss of normal power to the area, so they go on the unswitched leg. Wiring them switched means they fire every time somebody turns the lights off.
• Dark spots between units. Passing the average and failing the 0.1 fc minimum in the gaps.

When you are already in the ceiling

A lighting retrofit is the cheapest moment in a building's life to fix egress lighting. The lift is already there, the ceiling is already open and the crew is already on site. Inventory the emergency units in the same walkthrough as the fixture count, and price the replacements into the same job rather than coming back for them.

Many utility rebate programs also cover emergency and exit fixtures as their own category, so it is worth checking the table rather than assuming they are excluded. See how utility rebates work, and foot candle targets by space for the normal lighting layer.