Rant: CO detectors

[jim]

What they explained to me is that CO detectors build up readings, and actually become overly sensitive at the end of their life. My situation Sunday was weird in that I should have never had an alarm go off, the house was at levels way below that, but yet it was at levels above what is considered normal. So the fire dept. was there quite a while, and they actually had to call the gas company to come out and check everything again.

So how would I have gone about telling them it was not an emergency? I'm not sure it was possible, they could hear the beeping of the alarm going off and no amount me telling them we were safe and outside was going to convince them imo. And maybe that's not a bad thing, but it sure seemed overkill. I mean that truck was [expletive] HUGE. It was like the biggest damn fire truck I have ever seen. And then behind them was the damn paramedics.

[stlouie_lipp]

I can see why emergency personal err on the side of caution and get to a call as soon as they can...and that means sirens blazing.

[AWvsCBsteeeerike3]

Those sirens scare me.

[lukethedrifter]

newer detectors generally have a ppm reading. does yours? if so it likely has a peak reading which would tell you just how high it had gotten and whether it should have alarmed or not. Certainly there are malfunctions, though typically those made in the last decade are much better about accurately alarming than the older ones.

not so sure that what they told you is accurate.

[jim]

No reading. The ones I just bought don't have it either, because I didn't want to spend the money. That was like a case of good beer difference in price, which over the course of 10 years is like a drop of beer every day. That adds up.

It is weird that both were going off at the same time, it's a new house (for us) and I thought maybe somehow they were sync'ed together. They weren't even wired, so that wasn't the case. But then again, the fire alarm started chirping an hour later (that little chirp that tells you the batteries are dead), and that is just the fire detector.

What they told me was that over time the CO builds up in the sensors and that it can falsely think that there has been levels of CO for longer periods of time than their really was. It didn't make much sense to me to be honest.

[lukethedrifter]

I believe that they had misinterpreted the following and gave you bum dope:

Will exposure to other household gases or vapors cause the CO alarm to sound a false alarm?
When UL evaluates samples of residential CO alarms, consideration is made that your home may contain moderate levels of cleaning chemicals and other substances. UL 2034, the Standard for Safety of Single and Multiple Station Carbon Monoxide Alarms, UL engineers and technicians use to test residential carbon monoxide alarms, includes exposure tests to normal concentrations of methane, butane, heptane, ethyl acetate (nail polish remover), isopropyl alcohol (rubbing alcohol), carbon dioxide and propane; all of these are gases typically found in a home.

You should, however, keep these chemicals away from your CO alarms. Low exposure over an extended period of time could damage the sensing device and cause it to sound a false alarm.

First, the smoke detector low battery alarm was completely unrelated and caused by a low battery state*. Second, I'm not sure but there may be wireless detectors that communicate but I don't think that is what you have. Thirdly, without a ppm readout, you- and they- have no idea what levels were reached. My diagnosis that you threw away perfectly good CO detectors unnecessarily and that your grill elevated levels high enough to set off both CO detectors then dropped when you opened the door, was probably already dropping as the coals went out.

Feel free to pass on the info to your local FD.


*if your house is possessed I retract that statement.

[jim]

I believe that they had misinterpreted the following and gave you bum dope:

Will exposure to other household gases or vapors cause the CO alarm to sound a false alarm?
When UL evaluates samples of residential CO alarms, consideration is made that your home may contain moderate levels of cleaning chemicals and other substances. UL 2034, the Standard for Safety of Single and Multiple Station Carbon Monoxide Alarms, UL engineers and technicians use to test residential carbon monoxide alarms, includes exposure tests to normal concentrations of methane, butane, heptane, ethyl acetate (nail polish remover), isopropyl alcohol (rubbing alcohol), carbon dioxide and propane; all of these are gases typically found in a home.

You should, however, keep these chemicals away from your CO alarms. Low exposure over an extended period of time could damage the sensing device and cause it to sound a false alarm.

First, the smoke detector low battery alarm was completely unrelated and caused by a low battery state*. Second, I'm not sure but there may be wireless detectors that communicate but I don't think that is what you have. Thirdly, without a ppm readout, you- and they- have no idea what levels were reached. My diagnosis that you threw away perfectly good CO detectors unnecessarily and that your grill elevated levels high enough to set off both CO detectors then dropped when you opened the door, was probably already dropping as the coals went out.

Feel free to pass on the info to your local FD.


*if your house is possessed I retract that statement.

First, I agree. It was just weird.

Second, they certainly were not wireless. Different brands/models. I'm certain that the levels were high - when did they bump up the amount of CO that is needed to sound the alarm? Maybe I have older models that were set to trip at 20 or something? I know that at low levels they have to be at that level for like a half hour, which is possible with the grill burning the coals. The reading was 19 when the fire dept got there, 13 by the time the gas guy got there 30 minutes later (and after we had some windows open). We did open a window at first, but then when waiting for the fire truck we decided to go back in and close it so we could get a true reading on the CO. I didn't want to air out the house and hide a potential problem.

Third, the detectors all were past the end of life. They were 5 year old detectors that were all 6 > years. As far as the grill, the thing is that I had finished cooking for a while. I think the coals were still burning, and I actually think my wife moved the grill and put it closer to the vent, so that was probably what did it. The thing was that the fire dept. wasn't sold that it was the grill, but it seemed obvious to me that is what it was. In fact, I didn't even think of it until the 911 operator told us to go outside, and when I sent out I saw the grill and realized I was probably looking at the culprit. I bought 10 year detectors with sealed lithium batteries - so shouldn't have to worry about this for a while.

[lukethedrifter]

Of course you will. Your detectors worked correctly so getting new ones won't change anything.

FYI smoldering coals give off far more CO than free burning coals.

[AWvsCBsteeeerike3]

Overall, this is a pretty awesome story. Equally funny, really, is that jim -through his own actions- elevated the carbon monoxide in his house to a level deemed dangerous enough just years ago to set off alarms and likely high enough to give ole jim a headache. The alarms went off, effectively doing their job, and jim starts a rant about them.

Awesome! If only it had been snowing out as he was waiting for the emergency crews to get there...

[Radbird]

I spent a good part of last weekend chasing down chirping smoke detectors, honing my 9-volt battery swapping skills.