# Should I have explosive gas alarm?



## Ultrarunner2017

Hi;
I had two Kidde KN-COEG-3 Nighthawk combo CO/Explosive Gas alarms, one in the basement, one in the dining room, at the door to the kitchen.
I have other CO only alarms in the house, as well as a wired smoke alarm system.
I had the COEG alarms to warn me if there was a natural gas leak. The house has gas heat, a gas dryer, and gas stove and oven.

Now, these alarms have expired (were 6-7 years old). One went bad about 1yr ago, the other just displayed the err message indicating that it is defective.
So, my question is should I replace the alarm(s) or is it really not worth the extra $45 per alarm to have them? I mean, how likely is it that a natural gas leak would develop while we're asleep and wouldn't smell the gas first?

These alarms would often false. If I sprayed Lysol in the bathroom, which was 20 feet away from the alarm in the basement, it would go off. It seems that everything would set them off - but I never had a natural gas leak.

I am looking at these alarms on Amazon, and many of the reviews say that there are a lot of false alarms with this type. Is this inherent to the EG tyep alarm, or just this model?

Thanks for your advice

FW


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## oh'mike

Good grief, I never heard of those----I am not a great worrier,so I do not see a need--but it's your house---Mike----


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## raylo32

From what I understand the explosive gas alarms are more for propane installations than NG. Propane is heavier than air and a very small leak can pool near the floor level over time and create an explosive hazard where the same NG leak would not create a hazard since it would dissipate more quickly. So I do have CO detectors but no explosive gas detectors for my NG house. But I guess it can't hurt to have them if it makes you feel safer.


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## Ultrarunner2017

From what I have been reading on this, most people feel that the frequency of false alarms from the EG alarms reduce their usefulness. That said, the reviews I have read are only for the household type that I might consider purchasing, not the more expensive, and more reliable ones used in some industrial facilities.

The reason I purchased my alarms is a long story, based on a co-worker's experience, which was an extremely rare situation. But even in his case, where there was a substantial gas leak at night, no one died or was injured, as there was no explosion.

The first time I ever owned an EG alarm was when I built one from a kit I bought at Radio Shack. It was all that was available at that time. My mom wanted me to install it because my bedroom was in the basement, and we have a gas fired furnace.

I believe in preventative maintenance, and am regularly checking for gas leaks. I check the flexible pipes used on gas appliances periodically. I also have an excellent sense of smell, and am aware when even the slightest amount of gas gets into the air.
In one review of the EG alarms, it was recommended for people who have lost their sense of smell and have gas appliances.
Apparently, most gas utilities do not recommend them.

FW


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## GBrackins

a lot of spray cans use a hydrocarbon mixture as propellant, probably the reason for the alarm to activate. Check your aerosol cans for listing of propellant.


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## yuri

Only explosive gases I worry about are self generated after chili night.:laughing:

Natural gas is VERY safe and few people know that you have to have a perfect mix of gas and air (4-14% gas/air) B4 it will explode and then you need a spark etc. Propane is dangerous and a Propane gas detector is recommended which will be specific for it. Natural gas has an odorant added to it ( mercaptan ) by the utilities which may fool these EG detectors and that is why the utilities don't recommend them. Plus they don't like false alarms and having to go check them. Explosive gas detectors are more for people who have to enter confined spaces where there may be methane etc ( sewer workers or underground utility workers ). Pure natural gas has no odor so those detectors are designed for that and probably not the natural gas we get in houses and therefore may not work.


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## beenthere

KE2KB said:


> Hi;
> I had two Kidde KN-COEG-3 Nighthawk combo CO/Explosive Gas alarms, one in the basement, one in the dining room, at the door to the kitchen.
> I have other CO only alarms in the house, as well as a wired smoke alarm system.
> I had the COEG alarms to warn me if there was a natural gas leak. The house has gas heat, a gas dryer, and gas stove and oven.
> 
> Now, these alarms have expired (were 6-7 years old). One went bad about 1yr ago, the other just displayed the err message indicating that it is defective.
> So, my question is should I replace the alarm(s) or is it really not worth the extra $45 per alarm to have them? I mean, how likely is it that a natural gas leak would develop while we're asleep and wouldn't smell the gas first?
> 
> These alarms would often false. If I sprayed Lysol in the bathroom, which was 20 feet away from the alarm in the basement, it would go off.
> 
> The aresol in many spray cans is flammable, so it is an explosive gas.
> 
> It seems that everything would set them off - but I never had a natural gas leak.
> 
> I am looking at these alarms on Amazon, and many of the reviews say that there are a lot of false alarms with this type. Is this inherent to the EG tyep alarm, or just this model?
> 
> Thanks for your advice
> 
> FW


The real question is, what is your piece of mind worth to you.

http://www.nbcdfw.com/news/local/Fi...e-Explosions-in-Tarrant-County-236288991.html

Here is one whee LP was pouring into the basement and they didn't smell it.
http://www.capemaycountyherald.com/article/news/court+house/97226-couple+brings+suit+home+explosion


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## gregzoll

Matter of fact, we just had a house explode, due to a leak from the incoming line from the Propane tank.

People reported that they could hear and feel the explosion in two counties.

As for the OP, if you want that peace of mind, it is up to you. If your Furnace and Water heater are in an enclosed space with a main waste drain in there, then I would say yes it would be worth it.


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## yuri

Propane I definetly would want a dedicated approved for Propane detector at floor level. Thought I heard it was code in RVs and probably will soon be in the bdlg code too.


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## gregzoll

yuri said:


> Propane I definetly would want a dedicated approved for Propane detector at floor level. Thought I heard it was code in RVs and probably will soon be in the bdlg code too.


It should be. CO detectors are required. The story on the local house explosion can be read about at wics.com, the local ABC affiliate.


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## Ultrarunner2017

gregzoll said:


> Matter of fact, we just had a house explode, due to a leak from the incoming line from the Propane tank.
> 
> People reported that they could hear and feel the explosion in two counties.
> 
> As for the OP, if you want that peace of mind, it is up to you. If your Furnace and Water heater are in an enclosed space with a main waste drain in there, then I would say yes it would be worth it.


There is no waste drain in the furnace room, but I can see your point. If there were to be one, and a leak caused the sewer to fill up with gas, then it would be a serious issue. If our gas utility decides we should have one, then we will purchase one through them, but at this time, they are not even mentioning explosive gas alarms on their safety pages.


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## beenthere

They should have had one in this apartment complex.

http://lancasteronline.com/article/...causes-gas-explosion-and-fire-in-Ephrata.html


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## Ultrarunner2017

beenthere said:


> They should have had one in this apartment complex.
> 
> http://lancasteronline.com/article/...causes-gas-explosion-and-fire-in-Ephrata.html


Scary. The service guy wasn't even a DIY'er, was he.
Thing about explosive gas alarm, it really needs to be wired into a whole-house alarm system so that residents can hear it. The ones I had were not, and I don't think anyone would have heard it from the basement on the 2nd floor (where we sleep) anyway. If I do install another one, I will want it to be wired into my smoke alarm system, which is just a bunch of interconnected smokes, no central console.


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## beenthere

KE2KB said:


> Scary. The service guy wasn't even a DIY'er, was he.


Nope, a maintenance guy for that complex that made a big mistake.


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## kimberland30

Glad I stumbled on this. What was your decision?

We also have NG and we need to replace all our smoke alarms in the house. I saw a 4+ unit (EG, NG, Smoke, Fire) but it is a hard-wired model. I was thinking of putting one in our laundry area (hot water heater), near the kitchen (gas oven/stove), one in the hallway near the bedrooms, and one in the den. It will be about $200 for the set. Our house isn't prewired for a system (built in 1960). How hard would it be to install these? Or should we just spring for new smoke alarms and get a special CO/NG alarm for the kitchen/laundry?

ETA: We have a 1-story ranch. No basement to worry about.


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## Ultrarunner2017

kimberland30 said:


> Glad I stumbled on this. What was your decision?
> 
> We also have NG and we need to replace all our smoke alarms in the house. I saw a 4+ unit (EG, NG, Smoke, Fire) but it is a hard-wired model. I was thinking of putting one in our laundry area (hot water heater), near the kitchen (gas oven/stove), one in the hallway near the bedrooms, and one in the den. It will be about $200 for the set. Our house isn't prewired for a system (built in 1960). How hard would it be to install these? Or should we just spring for new smoke alarms and get a special CO/NG alarm for the kitchen/laundry?
> 
> ETA: We have a 1-story ranch. No basement to worry about.


If you are comfortable with wiring, installing smokes is no more difficult than anything else. You need 3-wire cable (usually 14/3) for the interconnected ones. Put the smokes on their own 15A breaker. In some areas (check your code) you are required to install AFCI (Arc-Fault Circuit Interrupter) breakers.
The most difficult part of the job is getting the cable from one place to the next.

FW


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