Your garage door is the largest and heaviest moving object in your home. A double door can weigh 300 pounds, it moves over the spot where your kids run out to the car and your dog wanders in and out, and most families never test whether its safety features still work. That’s the gap I want to close today. I’m Shelby Palmer, founder of FixDoor in Marble Falls, and garage door safety is the part of this trade I take most personally. The good news is that checking it takes about two minutes and zero tools.
The two safety systems every opener should have
Since 1993, federal law has required residential garage door openers to include two layers of protection, under a safety standard called UL 325. Knowing what they are tells you exactly what to test.
- Photo-eye sensors. Two small sensors mounted about four to six inches off the floor on each side of the door. One sends an invisible beam to the other. If anything breaks that beam while the door is closing, the door is supposed to stop and reverse.
- Mechanical auto-reverse. The opener also senses resistance. If the door contacts an object on the way down, it should reverse on its own, even if nothing crossed the beam.
Those two systems are why a closing door is supposed to bounce back off a tricycle instead of crushing it. They exist because, before they were required, children and pets were killed by closing doors. The U.S. Consumer Product Safety Commission pushed for these standards after those tragedies, and they have prevented countless injuries since.
The 2-minute test (do this today)
Run both of these checks. If your door fails either one, the safety system needs attention now, not eventually.
Test 1: the reverse-on-contact test
Lay a flat board or a roll of paper towels on the floor in the center of the doorway, where the door will land. Close the door with the opener. The moment the door touches the object, it should stop and reverse. If it keeps pushing, sits on the object, or only stops without going back up, the auto-reverse force is out of adjustment or failing.
Test 2: the photo-eye test
Start the door closing, then wave a broom handle or your foot through the opening, down low near the floor where the sensors are. The door should immediately stop and reverse. If it keeps closing, your sensors are misaligned, dirty, or failing.
Why sensors fail, and why you should never tape over them
Sensors are simple, which is exactly why people abuse them. Out here, the usual culprits are a bumped bracket, sunlight washing out the beam in the afternoon, spiderwebs and wasp nests blocking the lens, or a little corrosion on the wiring. When a door won’t close and the light blinks, those eyes are usually the reason.
Please don’t do the thing I see far too often. When the door won’t close, people tape the button down or twist the sensors to point at each other from the ceiling so the door closes no matter what. That doesn’t fix the problem, it removes the one feature standing between a 300-pound door and whatever is underneath it. If your sensors aren’t working, get them realigned or replaced, don’t disable them.
I take this seriously enough that I personally handle the annual UL 325 safety service for the Marble Falls Fire Rescue station. The same standard that keeps a fire bay safe is the one protecting your kids in the garage.
What UL 325 means for your house
You don’t need to memorize the code. What matters is the principle behind it. A powered door has to be able to detect a person, a pet, or an object and stop. On homes that means the photo eyes and auto-reverse. On commercial and rolling steel doors it can mean monitored edge sensors too. When any of that is bypassed or broken, the door is no longer meeting the safety bar it was built to. A quick garage door sensor alignment usually brings a stubborn door back into line.
If your door fails the test
Stop using the automatic open and close until it’s fixed, and use the manual release if you have to. Then get it looked at. The honest part you’ll appreciate: a failed safety test is usually a cheap fix. A realignment, a cleaned lens, a fresh pair of sensors, or an adjustment to the opener’s force setting solves most of these. It is rarely a new opener, and any tech who jumps straight to selling you one is skipping the easy answer. You can read more about how we approach this work on our about page, or see our full range of emergency repair help if your door has stopped working entirely.
Frequently Asked Questions
How do I know if my garage door sensors are working?
Run the broom-handle test above. Wave something low through the opening as the door closes. A working system stops and reverses immediately.
My garage door won’t close and the light is blinking. Why?
A blinking opener light almost always means the photo eyes are misaligned or blocked. Check for a bumped sensor, a dirty lens, or sun glare before anything else.
Can I disable my sensors temporarily?
I’d strongly advise against it. The sensors are the safety feature. If the door won’t close, get the sensors fixed rather than bypassing them, especially with kids or pets around.
Are older garage door openers safe?
Openers made before 1993 may not have auto-reverse at all. If yours is that old, have it evaluated. The safety improvement alone is usually worth the upgrade.
Want a professional safety check?
Call us at (830) 362-2763 or 830-251-4722, or reach out through our contact page. We answer the phone, we show up when we say we will, and we will tell you the truth about your door even when the truth is cheaper than you expected.
About the author: Shelby Palmer is the founder and lead technician of FixDoor in Marble Falls, Texas. He is a second-generation garage-door man who grew up in the trade his father built in Dallas-Fort Worth, and he has spent decades on the tools, on the phones, and consulting for some of the largest door companies in the country. He services the UL 325 safety compliance for Marble Falls Fire Rescue, and he runs FixDoor on a simple promise his customers know by heart: Better, Faster, Humble.
