Why The Design Guy is Dangerous

So, being in the fire prevention business, I am one of those people who used to actually test the smoke detectors in the house regularly. By that I mean, I go and look at it, see that the little green light is on saying the battery is ok and then press the test button to hear it sound off.

Back before My Queen, I lived very compactly. As in one 15’x10′ room. Being a technical kind of guy, creature comforts were never a big deal to me. In that room, was my TV, stereo, bed, my office chair and desk and computers. I lived, slept and worked in there for a decade. Only thing it didn’t have was a kitchen, for that, I had to travel down the hall to another room.

This started after I finally got smart enough to leave my first wife. Being fairly poor I rented my old bedroom from Mom. Later, she moved out to live with her boyfriend and I had the whole house to myself. Much to the irritation of my buddies, I didn’t spread out to the rest of the house. I liked compact.

So, one night I go into the kitchen and put me on a pot of spinach, which was halfway between a meal and a snack in my thinking. I had a craving. The phone rings, it’s business, my favorite customer. He likes me a lot and he likes to talk, so we talked as usual for quite a while. Long enough for me to get sidetracked from the task at hand.

I always closed the door, to keep my pet cockatiel, Bitey, from roaming around the house. So, there I am, working away on the computer with the door closed.

After a while, I suddenly smell smoke. This jogs a distant memory of a pot of spinach I turned on about an hour and a half ago. I run toward the kitchen. As I open my door, the smoke in the hall is thick enough at eye level as to make it impossible to see. In the kitchen I grab the pot of flaming spinach and toss it in the sink and turn on the water. I do a quick check of the cabinets to see if anything else is on fire, surprisingly they are quite cool.

Panic over, I have this interesting thought: Why didn’t the smoke detector go off? In fact, why isn’t it GOING OFF right now? I walk into the hallway. The smoke is still thick enough at the ceiling that I can’t see the detector. However, I can see the flashing green light.

How reassuring, the battery is ok. So I reach up and press the test button. The alarm sounds. Therefore it’s working perfectly. I was obviously wrong about how it works, I assumed that it detected smoke and then sent the alarm. I now realize that the way it works is, when you detect smoke, assuming, I guess, you’re not on fire, you should run to the hallway and press the test button…

Thing is, I expect the test button to fail if the detector itself has failed, obviously in this case, that’s not how it was wired. The “test” button only tested the speaker, not the entire device. Had I been asleep, I might not be here to make this post. Granted it was my own stupidity that started the fire, so the first and worst failure was mine. But a device, especially a safety device, should work as designed if the test indicates it is working.

You might wonder why I didn’t mention a brand name. Well, the reason is I don’t know, at the time I was more interested in why the test failed to detect a fault and I simply tossed the detector. And, most likely, all of the detectors on the market probably have the same circuit board. I doubt there are that many different manufacturers for that. What I did do was redesign my test for the device. I test them by holding a smokeless flame near enough for them to detect it. I use ionization type detectors, I expect them to be able to detect a candle flame held a foot or so under them.


I figure one of these days I’ll come across another malfunctioning detector, if I do, I’ll play with it and see if setting it on fire sets it off.