Are Exit Signs Required by Law? Everything You Need to Know

You've walked past them a thousand times. That little red glowing rectangle above the door that you've never once needed—and hopefully never will. Exit signs are so ubiquitous that they've basically become wallpaper. But here's the thing: if you own, manage, or operate a commercial space, those signs aren't optional decor. They're a legal requirement, and there are more rules about them than you'd expect.

Let's break it down, from what the law says and where signs have to go, to what you actually need to buy in order to stay compliant.

Who's Actually Making the Rules?

Exit sign requirements come from a few different places, and they all layer on top of each other depending on your building type and location.

OSHA (the Occupational Safety and Health Administration) covers workplaces and sets the federal baseline. Under OSHA standard 1910.37, every exit must be clearly visible and marked by a sign reading 'Exit.' The letters have to be at least six inches tall with a three-quarter-inch stroke width—meaning the actual thickness of each letter. Signs must be illuminated to at least five foot-candles (that's a measure of light intensity) by a reliable source, and they must be distinctive in color.

NFPA 101, the Life Safety Code published by the National Fire Protection Association , goes further—it's the standard most state and local building codes adopt, and it governs everything from how far apart signs need to be to how long the battery backup has to last. (Spoiler: 90 minutes minimum.)

The International Building Code (IBC) adds another layer for new construction and major renovations. Most jurisdictions in the US have adopted some version of the IBC, which means your local building department is likely enforcing its exit sign placement rules alongside NFPA 101.

Your Authority Having Jurisdiction—the AHJ, which is usually your local fire marshal or building department—has the final say on what's required in your specific building. When in doubt, call them.

Where Do Exit Signs Actually Have to Go?

This is where most people get tripped up. It's not just 'above the door.' The placement requirements are specific:

·         Above every exit door: Any door that leads to an exit must be marked. That includes stairwell doors, corridor exits, and exterior exit doors.

·         At every change of direction: If someone walking through your building can't see the next exit door from where they're standing, there needs to be a sign pointing the way — at every turn, every junction, every point where the path isn't obvious.

·         At corridor intersections: Hallways that cross or branch require directional exit signs so people aren't guessing which way to go at 2am during a fire alarm.

·         Maximum 100-foot intervals: Along any corridor, exit signs must be placed so no one is ever more than 100 feet from the nearest one.

·         Mounting height: Typically mounted between 80 and 96 inches above the floor, or directly above the door. The sign has to be in the line of sight — not hidden behind ductwork, not blocked by shelving.

·         Doors that are NOT exits: Any door along an exit path that could be mistaken for an exit must be labeled 'Not an Exit' or marked with its actual use (storage, mechanical room, etc.). This one gets overlooked constantly.

The underlying logic is simple: in a smoke-filled, panicked environment, people need to be able to find the exit without thinking. The placement rules exist to make sure that's actually possible.

The Battery Backup Requirement (Yes, It's Real)

Exit signs can't just be plugged into a standard circuit and called a day. They're required to have a backup power source that keeps them illuminated for at least 90 minutes during a power failure — per NFPA 101 and most state codes. This is non-negotiable for most commercial applications.

The 90-minute window gives occupants enough time to evacuate and gives first responders enough time to move through the building safely. It's also why LED exit signs have largely replaced older incandescent and fluorescent models — LED draws so little power that the same battery capacity lasts dramatically longer, which means less maintenance and fewer failed-battery compliance issues.

Most modern LED exit signs have the battery built in and self-test automatically. Some are required to have a manual test button and indicator light so you can verify the backup is working during routine inspections.

Red or Green — Does It Matter?

Yes, actually, though it's not always a legal distinction in the US. Traditionally, US exit signs use red lettering — that's the OSHA and NFPA standard color, and it's what most American inspectors expect to see. Red means 'this is how you get out.'

Green exit signs are used internationally—Canada, the UK, Europe, and most of the rest of the world use the ISO 7010 standard, which uses a green running-figure pictogram instead of the word 'EXIT.' Some US jurisdictions accept green as an alternative, particularly in buildings with international guests or tenants, but you should always verify with your local AHJ before going green.

Both colors are available and code-compliant in many jurisdictions. The short version: red is safe anywhere in the US, green is fine in most places but worth confirming first.

What to Actually Buy

Here's where I get to be genuinely useful. Sunco has a full lineup of exit signs that cover pretty much every commercial and institutional situation:

The LED Exit Sign (Red), Damp Rated is the no-frills baseline — 2W, 120-277V (meaning it works on both standard residential and commercial voltage), with a built-in backup battery and knockout directional arrows. Letters are 6 inches tall with a 3/4-inch stroke, so it meets OSHA's letter-size requirement out of the box. At $17.99, it's the easy answer for straightforward installs.

If you need the sign to also double as emergency lighting, the 2 Head LED Exit Sign (Red), Floodlight adds two adjustable LED flood heads on either side of the sign. The heads swivel to illuminate the path to the exit — which is useful in longer corridors or spaces where a separate emergency light isn't practical.

The Black 2 Head LED Exit Sign is the same product in a black housing for spaces where aesthetics matter—think hospitality, upscale retail, corporate offices. Compliance doesn't have to look like an afterthought.

Going green? The 2 Head LED Exit Sign (Green) works in jurisdictions that accept green lettering and in buildings where international occupants are the norm. Same specs as the red version — 3.3W, 300 lumens, 90-minute backup battery.

For spaces where you genuinely can't run power — storage rooms, remote stairwells, temporary installations—the Photoluminescent Exit Sign Sticker, Glow in the Dark charges under ambient light and glows without any electricity. NFPA 101 does allow photoluminescent signs in certain applications (they have to meet a specific luminance threshold), so check with your AHJ, but for supplemental marking or low-occupancy spaces, these are a genuinely practical option at $1.99.

And don't forget the companion piece: emergency lights. Exit signs tell people where to go; emergency lights make sure they can see to get there. Sunco's 2 Head LED Emergency Light pairs naturally with any of the exit signs above—adjustable heads, 90-minute backup battery, 120-277V. Most building codes require both.

You Also Have to Maintain Them

Buying the right sign is step one. Keeping it compliant is ongoing. OSHA requires that safeguards like exit signs be 'in proper working order at all times.' In practice, that means:

·         Monthly testing: Most codes require a 30-second functional test of the battery backup every month.

·         Annual testing: A 90-minute full-duration test once a year to confirm the battery can actually run for the required time.

·         Visual inspections: Signs should be checked to confirm illumination, visibility, and that nothing is blocking the line of sight.

·         Replacement: If a sign fails a test or the lettering becomes damaged, it needs to be replaced before the next inspection. 'I meant to order a new one' isn't a defense during a fire marshal walkthrough.

LED exit signs make this a lot easier than older technology. Battery life is longer, bulbs don't burn out, and the power draw is low enough that the backup systems last significantly longer between replacements.

The Bottom Line

Exit signs are one of those things that feel like background noise until they're not—until there's a power failure, a smoke condition, a panicked crowd, or a fire inspector with a clipboard. The legal requirements exist because people have died in buildings where the exits weren't clearly marked or the signs went dark during an emergency.

If you're outfitting a new space, doing a renovation, or just realizing your current signs are aging out, now's a good time to get it right. The rules are specific, but they're not complicated once you understand them. And the products that meet those rules are simpler and cheaper than they used to be.

Get the right sign for the right location, make sure it has backup power, and put it where people can actually see it. That's mostly it.