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How do I know if my CO alarm went off because of Carbon Monoxide?

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 OK so I've been searching through and what I'm wondering is is when it goes off and you think it is a carbon monoxide excess what do you have to do to be able to get back into your home, just open windows and air it out and for how long? Do you have to come in and scrub walls wash fabrics?

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Carbon monoxide does not smell and is colourless, so there is no point in scrubbing or cleaning anything.

How long you ventilate depends on how much ventilation is carried out and the duration of said ventilation.

If you were to open a small window in one room and there is no "through draft" it would take considerably longer to ventilate than if you were to open all the windows in the house (and doors to allow a through draft)

A carbon monoxide alarm will stop sounding when the levels are safe.

I would also make a physical note of the time and what appliances were on at that time, and also was anyone parked outside / in the garage (if you have one) as cars also give out carbon monoxide. The idea being if it happens often you should soon be able to track down the cause of the carbon monoxide.

 

  • 2 months later...

Please help, family of 6 here. 1am I heard 4 beeps, then a long pause, then 4 more beeps. It's been over an hr almost 1.5 hr. Nothing after. I'm not even positive it was co alarm just have never heard this alarm in my life so am worried. Thanks

If it was 4 beeps in succession it may be that you have a "fire angel" CO alarm and that it did detect CO But if there is lots of CO then the detector would NOT stop beeping. Why don't you press the test button on the CO alarm to find out what it sounds like.

  • 5 weeks later...

My Co alarm went off last week 4 beeps then paused then 4 beeps then paused. I called 999 as was told to. Then cleared us out flat and aired flat. Turned off main gad and next day gas man came out to confirm we had a leak. Just goes to show u never leave it as we changed battery and it stoped and we had a leak. It saved our life's. 

  • 4 weeks later...

A carbon Monoxide (CO) detector will not detect natural gas which is principally methane (CH4) but you can get detectors that will recognise methane and carbon monoxide. Natural gas can be detected by smell but carbon monoxide cannot so it is very important that you keep your CO detector in good working order.

I think this incident was a coincidental but nevertheless the outcome was great.  

  • 2 months later...

My Carbon Monoxide detector went off last night. We thought nothing of it. There was nothing on, no stove, no heat. How do I know this wasn’t faulty 

People often say "oh it's faulty" (About most things) when in fact it isn't.

Carbon monoxide itself is odourless and colourless  I would suggest that your CO detector did indeed detect carbon monoxide and that is why it activated (It was doing its job)

As for where the CO came from, no one can say, but I would check that your CO alarm is working by pressing its test button and making sure it is within its age limit. (They have a life expectancy of between 5 - 10 years, depending on make  / model)

We've just had an extension built and they came to do the floor screed today. Our CO detector went off late afternoon and my husband called British Gas who have since been and disconnected the gas supply, however, the detector has gone off again. A friend of a friend had the same experience when their floor screed went down - has any one else heard of this happening?

Hi Janie

I have not heard of screed setting off CO alarms, however, I am aware of one chemical that can set CO alarms off. The hydrogen generated when eg car batteries are charged reacts with the sensor in the same way as carbon monoxide does.

Please keep in mind that CO also can come from your neighbours  (if they have a vent on the outside, or from a shared roof space) and from the road if you are living next to a very busy road.

Harry

  • 1 month later...

My CO alarm went off about a half hour ago. I took it outside and it stopped, brought it back in, hit the test button and it went off again. Then, stopped and hasn't went off since. I opened all my windows and turned off my heat. I guess I should mention I live above a bar that just started renovations today. 

The problem with carbon monoxide is it colourless and odour less (So you can not see it) As there are renovations going on below you and the CO alarm has been ok previously its safe to assume its something the people doing the renovations that produced carbon monoxide. But as I said, they would not know they are producing carbon monoxide because you can not see it.

Hi. My mom was moving furniture near the detector and the alarm went off. What do I do now?

  • 4 weeks later...

So I've read through this whole thread and find it the most interesting. I just moved into this new apartment in a 2 family home. About 30mins ago all the alarms in the went off saying "warning carbon monoxide". I don't know what to do becuase the family upstairs is the landlord who just turned them all off and probably went back to bed because its really silent again. I'm genuinely scared, I've lost a loved one due to carbon monoxide and am not sure what to do.

Hi Angie

If there is more than one CO alarm going off at the same time, it is probably safe to assume that there was indeed carbon monoxide present and possibly at a dangerous level. You need to consider leaving the building til the source of the carbon monoxide has been identified as from your description there is a real risk to your health.

Depending from the potential source of the CO gas you need to ring one of the numbers shown on https://www.carbonmonoxideinfo.co.uk/what-is-carbon-monoxide/ so that an engineer can check the source of the gas.

Harry

 

After an hour or so the landlord came down to tell us that we needed to leave because he has a wood furnace that was causing the CO to get inside the house. But it got taken care of thank you.

  • 1 month later...

I have a log burner my co alarm sounded earlier but has now gone off. We have an open kitchen but hubby was cooking tea but also had fired up motor bike earlier, this is in garage off kitchen. Please advise

 

  • 2 weeks later...

Hello! Ok. So my CO alarm is a plug in one. My kid was standing by it, and my bf was cooking supper & I was cleaning. All of a sudden the alram went off, my child got scared & ran. I dont know if she touched a button or not.... I wasmt thinking & unplugged the thing so she would stop screaming. Then I realised I shouldnt of. I plugged it back in. And nothing. However, now there is a small res line on top that wasnt there before. 

Its been about 2 hours, we all feel fine but I keep thinking about it. Is there a way I can check if things are fine on my own?

Hi, have you checked that the alarm is still within date? Depending from model and manufacturer CO alarms last 5 to 10 years. If you feel you cannot call out an engineer to check things over, you could get a second battery-powered CO alarm to verify the first result. Alternatively, you could buy a CO gas test spray to make sure your alarm is working.

Harry

  • 2 months later...

What does it mean when there is a 97 on your co screen i woke up at 430am with this alarm.  The screen was on and it said 97

  • 2 weeks later...

Hi my co alarm was going off when I got home. I opened all the doors and it was still going off. I borrowed another co alarm and put it inside and that one never sounded the alarm even after 45 minutes. I took mine outside for 10-15 minutes and it still wanted to sound the alarm. I've turned off all the gas and have been airing the space for over an hour. It still wants to go off...its quite old...can I assume it's come to the end of its life and is faulty??

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