Carbon Monoxide Detector?

fiveoboy01

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I want one for my airplane.

Any reason I can't use the $30.00 First Alert one(shows PPM on a digital display, battery powered) over the expensive "aviation specific"(shows ppm on a digital display, battery powered) ones?
 
None. But if there is a quality difference, that is on you. Note, for all I know, the units you are comparing are identical.
 
I want one for my airplane.

Any reason I can't use the $30.00 First Alert one(shows PPM on a digital display, battery powered) over the expensive "aviation specific"(shows ppm on a digital display, battery powered) ones?
Check on the display range of the home unit. The one I bought only displays levels over 30 ppm. OK when you're looking for higher levels, but you'd like to know if there's a low-level ingress as well.

I ended up buying a semi-pro unit for $99.

Ron Wanttaja
 
I agree, you want to make sure you know what range the unit has, i.e. how low of a concentration of CO it can detect.
Often, the aviation units aren't much different from the home detectors (at a fraction of the aviation cost). So do your homework. Don't buy just the cheapest detector.
And stay away from fleaBay, they sell $6 units directly from China. No documentation, nothing. I don't think you need to ask why. ;)
 
Check on the display range of the home unit. The one I bought only displays levels over 30 ppm. OK when you're looking for higher levels, but you'd like to know if there's a low-level ingress as well.

I ended up buying a semi-pro unit for $99.

Ron Wanttaja

Thank you.

At what point should I be concerned about CO levels? The particular "home unit" I am lookin at(First Alert CO615) starts alerting at 30ppm..... isn't a very small amount "normal" due to air intakes for the cabin and such?
 
Thank you.

At what point should I be concerned about CO levels? The particular "home unit" I am lookin at(First Alert CO615) starts alerting at 30ppm..... isn't a very small amount "normal" due to air intakes for the cabin and such?
Depends on how much poison you want to imbibe.

US Standards allow a maximum of 35 ppm for one hour, or 9 ppm for eight hours. You can guess that a max for a 3-4 hour flight is going to be below 30 ppm. Also, these standard call for *one* such exposure per year.

My airplane shows ~80 ppm when taxiing with the wind on the right side (exhaust pipe on the right side, exhaust getting blown into the open cockpit), temporary hits at ~30 ppm during changes of power/attitude in flight, and a dead-steady 6 ppm in flight...which is exactly what it reads on the ground, in the hangar.

Lent it to a guy with a closed-cabin homebuilt, and he gets about the same readings in flight.

Nice thing about a unit that gives you the 0-30 reading is that you can hunt down and eliminate any slight leaks.

Ron Wanttaja
 

Yeah, I saw that in the instruction sheet. Unfortunately, there doesn't appear to be any indication in there as to how the LED displays PPM, if it's continuous, or if it only comes on with an alarm. Furthermore it only gives the UL requirements, and doesn't say if the detector is "more or less" stringent than those requirements. I'll assume that it just meets them. A friend with a Glasair has it and he said it was reading up to 36 at one point, but I didn't press him for details.

Currently I have nothing in the cockpit, and I don't suspect that I have a CO problem, but it's just something I was thinking about adding.
 
Depends on how much poison you want to imbibe.

US Standards allow a maximum of 35 ppm for one hour, or 9 ppm for eight hours. You can guess that a max for a 3-4 hour flight is going to be below 30 ppm. Also, these standard call for *one* such exposure per year.

My airplane shows ~80 ppm when taxiing with the wind on the right side (exhaust pipe on the right side, exhaust getting blown into the open cockpit), temporary hits at ~30 ppm during changes of power/attitude in flight, and a dead-steady 6 ppm in flight...which is exactly what it reads on the ground, in the hangar.

Lent it to a guy with a closed-cabin homebuilt, and he gets about the same readings in flight.

Nice thing about a unit that gives you the 0-30 reading is that you can hunt down and eliminate any slight leaks.

Ron Wanttaja
It was a reading between 10 and 20 ppm that led to the discovery of my plane's cracked muffler last winter. Not only was that reading higher than I had seen before, it went down to single digits when the heat was off and crept up again soon after turning it on. A good sensitive detector is very much worth it IMO since it can help you identify a problem before it becomes life-threatening.
 
I have a couple of fancy aircraft CO detectors but much prefer the stick-on dots that change colors when CO is present.
 
Yeah, I saw that in the instruction sheet. Unfortunately, there doesn't appear to be any indication in there as to how the LED displays PPM, if it's continuous, or if it only comes on with an alarm. Furthermore it only gives the UL requirements, and doesn't say if the detector is "more or less" stringent than those requirements. I'll assume that it just meets them. A friend with a Glasair has it and he said it was reading up to 36 at one point, but I didn't press him for details.

Currently I have nothing in the cockpit, and I don't suspect that I have a CO problem, but it's just something I was thinking about adding.

I brought my CO detector into the garage this morning and started my car. It displayed 0 for a minute or two and then buried the needle at 999 and started alarming. I took it outside and the PPM display updated every 5 seconds or so. The alarm stayed on as long as PPM>30. The last reading was 32, and then it fell to 0.

The FAA wants levels below 50 ppm (14 CFR 23.831 (a)).
 
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I brought my CO detector into the garage this morning and started my car. It displayed 0 for a minute or two and then buried the needle at 999 and started alarming. I took it outside and the PPM display updated every 5 seconds or so. The alarm stayed on as long as PPM>30. The last reading was 32, and then it fell to 0.

The FAA wants levels below 50 ppm (14 CFR 23.831 (a)).

Thank you. Which model CO detector do you have?
 
I have one of the Kidde ones by my furnace and water heater. The KWJ Pocket CO detector isn't that much more expensive, at least by aviation standards.
 
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I want one for my airplane.

Any reason I can't use the $30.00 First Alert one(shows PPM on a digital display, battery powered) over the expensive "aviation specific"(shows ppm on a digital display, battery powered) ones?
When I was researching just this question, I was led to believe that home CO detectors were unreliable at altitude.....then I found this from UL:
1. Underwriters Laboratories (UL) Research Project
The goal of the UL initiative is to determine if CO detection installed in high altitude applications (between 5,000 and 12,000 feet above sea level) provides adequate life safety protection. The genesis of this project actually started in 2009, when Colorado signed a bill into law requiring CO detection in one- and two-family dwellings and rental properties. Soon thereafter, several Colorado code authorities became concerned whether CO alarms or detectors installed in the Rocky Mountains would work properly. The reason for their concern is that the current edition of ANSI/UL 2034 does not contain test protocols to address the performance of CO alarms installed more than 530 feet above sea level.

Then in 2011, UL formed a Task Group (TG) to determine if CO alarms installed in altitudes up to 12,800 feet above sea level will activate within the ANSI/UL 2034 specified alarm thresholds, and requested that UL assess the performance of current CO alarms by conducting field sensitivity tests in Colorado.

As a direct result, UL collected 28 sample products from retail and internet outlets. The samples represented variants of the existing certified sensing technologies and were tested at the UL Northbrook Illinois facility for normal operation and sensitivity testing at approximately 560 ft above sea level. The same samples (and the UL test chamber) were then shipped to Colorado where a series of sensitivity tests were conducted at 5,200 ft in Denver and 10,000 feet in Breckinridge, followed by testing on Mt. Evans at approx. 12,000 feet.

All 28 CO alarms activated within the respective ANSI/UL 2034 alarm thresholds; however, several models did activate early at the 70ppm threshold at 10,000 feet and 12,800 feet above sea level.

Based on this information, a proposal to add high altitude performance test protocols to the ANSI/UL 2034 product standard is currently being reviewed by the Standards Technical Panel (STP). Once the proposal is approved by the STP, a future compliance will be established for all carbon monoxide alarms and detectors

So, although still not entirely a settled question, it appears, if anything, altitude may cause early alarm.
 
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