Are You Re-aa-lly “Testing” the Smoke Detector?

I’m sure most of us have reached up and pushed the “Test” button on the smoke detectors in our homes. Whether we did it as a routine to check it for operation, or to check the battery, or curiosity, the shrill noise that the appliance emits was enough to wake the dead, right?


What you may not know is that the onboard “Test” button does not actually indicate whether the detector alarm will work in an actual smoke and/or fire condition. That button will test the audible alarm (i.e., Does the noise part work?) and the battery (i.e., Is there enough “juice” in the battery to detect anything?).


The way to test the electro-chemical circuitry in the device is to test it with what some folks call “canned smoke” or actual smoke. We NEVER RECOMMEND the actual smoke method, and neither does the local fire department. The “canned smoke” method is the preferred method. We use it to test a home’s smoke detectors during our inspection; that is, unless the home has a security system. When a home has a security system, there is a distinct chance that the smoke alarms are “hard-wired’ into the security system. More than one home inspector can tell you about the fire department showing up to “put out a fire” that the inspector accidentally announced by testing the smoke detector.



1. Save the directions for installation of all new detectors, so that you can follow the manufacturer’s recommended instructions for testing over time.

2. If you are going to use the “canned smoke” method, you can purchase this product at most local home improvement stores. Follow the directions for use, and DO NOT OVERUSE the test. Overuse of the canned smoke can actually coat the sensing plates inside the detector. Again, follow the directions on the can.

3. Never take a battery out because the detector is chirping WITHOUT PUTTING A REPLACEMENT BATTERY BACK IN! If you silence the chirping, the chances are very good that you’ll forget to put a new battery in, and you could be tragically sorry.

4. It’s a good idea to change the batteries in your smoke detectors twice a year. Do it on New Year’s Day and July the Fourth. If you’re only going to do it once a year, and you haven’t actually heard the “Low Battery” beep going off already, change it on New Year’s Day. Make it an annual Holiday routine.

5. If you’re moving into a house you just bought, and the house is more than a few years old; if the smoke detectors look old and yellow and dingy; if the person who previously lived there smoked like a chimney; or IF YOU JUST WANT TO BE DILIGENT ABOUT YOUR FAMILY’S SAFETY – Replace the smoke detectors.

6. ALWAYS install new smoke detectors/alarms strictly according to the manufacturer’s instructions for placement and maintenance.

7. Here are the most recent national code recommendations for placement of smoke detectors in your home:

a. in each sleeping room;

b. outside each separate sleeping area, in the immediate vicinity of the sleeping rooms;

c. one each additional story of the dwelling, including basements (but excluding crawlspaces and uninhabitable attics)

d. in dwellings with split levels and without an intervening door between the levels, a smoke detector/alarm installed on the upper level and the adjacent lower level shall suffice, provided that the lower level is less than one full story below the upper level


One more thing, before we leave this subject. Next time your not paying attention to the bacon on the stove or bread in the toaster, and the nearest alarm goes off: Thank your lucky stars that the detector is doing its job. Reward it by allowing it to perform for you. Reward it by giving it a new battery on a routine basis. And reward yourself for taking care of your house — and more importantly, KEEPING YOUR FAMILY SAFE AND SECURE.


We invite your comments on this and our other articles. Please let us know if you have other topics you’d like to hear about in this section. And, remember, “It’ll feel more like home, when you’ve had a House Exam!”

Written by DFWinspector

House Exam is a professional home inspection company, licensed by the Texas Real Estate Commission (TREC 7195). Call us for the best home inspections Fort Worth TX has to offer. Our inspectors serve Fort Worth and the surrounding areas. Few home inspectors in North Texas can match our 30+ years experience in home remodeling and construction. Local address: 2318 Carleton Ave, Fort Worth, TX 76107, (817) 797-2461