11 Md. people being treated for CO poisoning

DanHolohan

<a href="http://www.wtop.com/?nid=598&sid=1993883">http://www.wtop.com/?nid=598&sid=1993883</a>

Jean-David Beyer

CO detector accuracy?

"after a carbon monoxide detector went off. Brady

says carbon monoxide levels were nearly 30 times what is considered

safe."



I never read about CO problems until this site started describing the problems people were having, including death. But this one concerns me. I have a detector upstairs, and another on the ground floor. (House has no basement.) I would like to think that these detectors would not wait intil the CO levels were 30x the level considered safe. My detectors say that with slight amounts of CO, it takes 1 to 4 hours for them to go off, but with high levels of CO they go off in a few minutes. My current detectors are quite new Kidde battery-powered ones and I replace the AA cells every year.



Is the variability of response of these units typically that high? Do they give us a false sense of security?

Tim McElwain

JD keep in mind the detector

going off does not stop the cause of CO (the water heater) from still operating.



The detectors you have are under standard UL 2034 which does not require them to ALARM until 70 PPM is reached and 240 minutes.



A low level detector from someone like CO Experts alarms at 9 PPM right away, low enough to give you plenty of warning and then follow the instructions on the detector.



See CO-EXPERTS

George Kerr

www.coexperts.com

Tim McElwain

JD keep in mind the detector

going off does not stop the cause of CO (the water heater) from still operating.



The detectors you have are under standard UL 2034 which does not require them to ALARM until 70 PPM is reached and 240 minutes.



A low level detector from someone like CO Experts alarms at 9 PPM right away, low enough to give you plenty of warning and then follow the instructions on the detector.



See CO-EXPERTS

George Kerr

www.coexperts.com

Jean-David Beyer

Interesting Idea...

You are right that the CO detectors I have wait up to 4 hours if 70PPM CO is around, 50 minutes if 150 PPM, and 15 minutes if 400 PPM. An old CO detector I had said this was on purpose as reflecting the susceptability of the human body to CO. Not only am I not a contractor, but I am not a doctor either.



But you stated: "the detector

going off does not stop the cause of CO (the water heater) from still

operating." I know you are correct about this, but would it not be a good idea if some models did cut off the source of CO if the limit were exceeded? Or would there be too many false alarms? I do not think so, but the only time one of my CO detectors went off, I did not need a CO detector to tell me something was wrong. During the summer, squirrels made a four-foot plug in my chiminey so when I started up my oil burner in the fall, smoke came out everywhere (except the top of the chiminey) and I turned the unit off as soon as I got to the circuit breaker to that boiler. Fortunately, the boiler was in my garage, so not much smoke got into the house. But the smoke detector and the CO detector both went off.

Tim McElwain

Yes it would be nice to

have the detector shut off the equipment. How is the problem as water heaters do not typically run on electric. Gas Range ovens would another problem and the list goes on. The answer is the low level non UL approved co detector. Then because it alarms at a low point you can shut things down and get a professional to come in and find the source of the problem.



Keep in mind long term exposure to co at low levels can be harmful to your health and that of family members especially the young, old and those with respiratory problems.

Jean-David Beyer

water heaters do not typically run on electric

I was taking too naaow a view, because in my house, the only thing that runs on gas is my home heating boiler, and turning off the 120 volt AC would make the thing stop. And this could be done either cutting that off (the same way the LWCO does) or by opening the circuit that is there for user-requested safety reasons. There are two such circuits, one that requires manual reset to restart things, and on that waits until the problem is resolved and automatically restarts.



And I have an indirect-fired hot water heater, so that should not produce any CO on its own.



Since my stove and clothes dryer are electric, that would not generate CO (except possibly at the power plant). And the gas stoves I have seen seem to be electric, to operate the clocks, timers, etc. But I do not know if that electricity could shut off the burners, and you are almost certainly right that it does not. My mother had an old gas stove until about 1950 that clearly had no electricity, no thermocouples in the burners, and none in the oven either. And newer gas stoves do not seem to have thermocouples in the stove-top burners either. So unless there is an electrically powered gas valve at the input to these things, that is out. Too bad, in a way.