There are two types of smoke alarm. One of 'em ain't so good.

I feel like this should go without saying, but, uh, don't go playing with that americium. Especially don't eat it. That's bad.

The clear 'No alarms go off' at the beginning was very very appreciated. Wish all professional folks could set expectations that way

Not only have you radically improved my dishwasher's performance; you have also upgraded my home's fire safety. I very much look forward to the next assistance I didn't know I needed. Thank you most sincerely!

Whoa!!!! My DAD was the Donald F. Steele whom you mention up front - he an Bob Enemark had the patent on the photoelectric smoke detector, with their company Electro Signal lab. He could have written your script - I grew up hearing the exact same explanation about how it worked, how it differed from the ionizations, and how the research backed up the fact that many many more people die of smoke inhalation than of actual flames. Great job!!!

As a Fire Electrical technician I often watch these types of videos to see if the presenter is actually giving out correct information, and also a person has to be open to maybe learning something new regardless of their background. I would therefore like to commend you on a very accurate, informative and knowledgeable video, and would recommend anyone who is interested in Fire Safety in their house (which should be everyone) to spend 25 minutes to watch this video as it will be time very well invested.

Those "nuisance" alarms almost killed us. I kept taking them down when we cooked. A nightmare I had about a fire caused me to buy one, single photoelectric alarm for the baby's room. Less than a week later, that was the ONLY fire alarm installed when we had an electrical fire at 4 a.m. we lost almost everything we owned but we lived and that's all that matters. I keep that melted smoke detector hung up in my garage. We owe our lives to that one smoke detector.... and that nightmare I had.

Funny story, I replaced all my ionization alarms with newer photoelectric ones, within a week I had one that went off on a regular basis, I took it down and opened it up to see what the issue was. Turns out that a small spider had taken up residence in the light chamber. My best guess is that he would pass through the beam occasionally creating a false positive. The other photoelectric ones have never had any such issues

After watching this I reached out to Kidde since I have a bunch of the dual sensor alarms in my home (Kidde Dual Sensor Battery Operated Smoke Alarm Pi9010). I asked "Does this product trigger the alarm when ONLY ONE sensor detects smoke, or when BOTH sensors detect smoke?" They replied "Only one of the sensors has to detect smoke to make the unit go into alarm." Might want to add a note about that since your preference away from this detector was based on the possibility that both sensors would need to detect smoke for it to go off.

My house hasn't had a smoke alarm in over 10 years. I bought one a few months ago and it's just been sitting in the project room. Because of this video I finally installed it. Thanks for the reminder.

As a 35 year veteran firefighter I want to thank you. And congratulate you on a very well presented report. As you stated, having alarms, maintaining alarms and heeding alarms is vital.

20 years ago I bought a wireless home alarm integratred smoke alarm that worked fine when pressing the test button. But I got the idea to test if it detected smoke or fire, and it didn't. I got it replaced at the store, and the replacement was just as bad. I really went overboard and charred it before returning it to the store. So yeah, good advice to test for smoke, the test button just tests the battery.

You pronounced "Jaeger" (or Jäger, the "ae" is simply an alternative way to spell the "ä" character) pefectly by the way. As a native german speaker, I am simultaneously very impressed and not at all surprised that you got it spot on.

I have to say, I used to call my smoke detector the ‘cooking detector’ because it basically went off whenever I did any kind of cooking. I eventually got frustrated and tore it off the wall. It’s great to know there is a better alternative - you might have just saved my life.

My grandmother still had in her home an ancient fire alarm that was a literal bell hit by a hammer driven by a wound spring. A piece of wax I believe held the hammer back unless the heat of a fire melted the wax. Needless to say, more modern fire alarms have been installed for decades, but we kept those up also as curiosities. They looked quite nice.

I work at a plastic injection company as a mold maker. I had no idea what the "Smoke Chambers" I worked on were used for. Thanks for this.

You had a dryer vented into your hallway? Don't do that. A dryer must be vented outside. Period. The lint dust can cause white lung disease like people who worked in cotton mills would get. I live in Ottawa, Canada, a climate similar to yours in Illinois. It's really tempting to want to save that warmth and humidity to make your indoor air better, but you will never filter out the finest lint particles enough. Also, you will slam your home with humidity and end up with condensation everywhere, possibly causing mold and other issues. Find a way to vent the dryer outside even if it means hanging the (metal, not vinyl!) dryer duct outside the window. Vinyl ducts are for bathroom fans only. Dryers do occasionally catch fire (ever forgotten a Bic lighter in your workpants?) and metal ducting is not going to ignite, while the vinyl will.

I actually work as a fire alarm tech! While we do test the smoke detectors with cans of fake smoke, there are several brands that actually recommend testing it via magnet or pressing a test button. It's because the fake smoke can leave an oily residue on the device if too much is sprayed or if it isnt blown out well enough with compressed air. This residue can then gather dust, making the detector less sensitive or, in severe cases, block it up completely. Personally I prefer using the fake smoke as it tests the sensors as well as the circuit and FACP. But in the event of a desensitized detector, we test the sensitivity of the detectors every other year, so if we find one that has become desensitized, we either clean it out or replace it. As far as home use goes, I think testing your smoke alarm with just the button is more than sufficient. Because you can gunk up the sensor with the fake smoke, I feel it would end up doing more harm than good as many people may over do it and end up clogging up the detector. And unlike commercial fire alarm systems, most/all 120V or battery powered detectors don't have the ability to test the sensitivity of the detector. So if a detector were to become desensitized, you would have no way of knowing.

That photoelectric alarm that went off every time the dryer was on likely failed due to lint! The microcontroller typically adjusts to the background level of radiant light detected. When dust builds in these detectors, they can sometimes trigger due to the reflectivity of the dust on the far side of the chamber bouncing light around. Sometimes it's because turbulent air will knock dust loose to float through the chamber. I can only imagine that, over time, tiny lint particles built up in the detector, so the air turbulence created by the dryer would knock that lint off the walls to float through the beam. For future reference, you can pop the cover off and clean out the sensor with canned air. Less plastic in the landfill!

So. Long time ago I recall being told that there were two types of detector alarms, smoke detectors and fire detectors. I always assumed the fire detector responded to heat and I even wondered how effective that might be since that meant they were probably calibrated to only go off after a certain temperature was reached. Now thanks to you I'm guessing the "fire detector" alarm was in fact this ionization thingie. As an aside, I once had a cooking oil fire on my stove. Unforgivably, I left a pan of oil on the stove and left the kitchen for a moment and then became distracted. A sudden whoosh and roaring sound brought me running back and the scariest thing was, except for the blinding flames I literally could see nothing else. There was like a vortex pillar of roaring vertical fire and otherwise it was completely pitch dark. I was terrified but I knew I had to put it out and at least I knew not to throw water on it. I got thick towels and edged up to it as close as I dared and gingerly plopped them over the pan. Everything in me wanted to toss the towels from a distance but the thought of toppling the pan and having burning oil everywhere stopped me. As soon as the fire went out I could see again. The lights were still on and there wasn't that much smoke at all. Its just that the fire was SO bright that it drowned out all the other light in the room. Its was like if you are in a dimly lit room and someone opens the door and the sunlight behind them is so bright all you can see is their silhouette. There might be more than enough light in the room for you to see them the moment they shut the door but as long as its open the sunlight totally overpowers the light in the room. That's what the fire was doing, it was so bright the rest of the room seemed pitch black. Lesson - when there's a fire you may well be effectively blind and unable to see exits or obstacles or where you fire-extinguisher is etc.

I worked at Bay Alarm for 16 years and we did use the canned smoke. It works well but I should cation, if overused it can damage the sensor in the detector by leaving a residue. So use it sparingly. Just the tiniest puff is all you need. Often you need to wait up to 30 seconds for that puff to do its job.