diligent about changing them, he or she may
get a false sense of security.
By contrast, the Pocket CO 300 uses an
electrochemical sensor containing
hydrochloric acid. A voltage is applied to the
acid, and the current flow is proportional to
the amount of carbon monoxide present. One
drawback is that the sensor slowly dries over
time. After about a year, it could read as much
as 10 percent lower, so KWJ Engineering
offers a calibration kit to recalibrate its
detectors. The kit includes an aerosol can and
a plastic pouch that the Pocket CO 300 is
placed in. Air from the can—which includes
100 ppm of carbon monoxide—is sprayed into
the pouch to expose the detector to a known
concentration of CO.
I like the Pocket CO 300 because it weighs
less than an ounce and is the size of a key fob.
It is so small that after I clip it to my shirt in
flight, I promptly forget it’s there. It can easily
attach to a key chain, a good place for most
pilots to carry it. However, as a flight
COMMON SYMPTOMS OF CARBON MONOXIDE POISONING: Headache, dizziness,
fatigue, nausea or vomiting, confusion, diarrhea, weakness, shortness of breath
IF YOU EXPERIENCE ANY OF THESE SYMPTOMS: Turn off cabin heat,
open windows, and land as soon as practical.
instructor, my keys are usually in my pocket,
so I store the Pocket CO 300 with my headset
so that I see it and am reminded to clip it on.
Wichita State analyzed where to mount a
CO detector and concluded that the
instrument panel was the most effective
location. Pilots could attach the Pocket CO
300 to the panel via Velcro, but I’m guessing
most pilots will want to leave it on a
keychain or use the clip to attach it
somewhere near the instrument panel.
The only downside I’ve heard is that the
Pocket CO 300’s 82-decibel buzzer isn’t as
loud as alarms in other detectors. But since
it also vibrates and flashes, you won’t miss
an alarm if it’s attached to your shirt.
This detector sells for $139 and can be
ordered at
www.KWJEngineering.com and
through many pilot supply distributors.
There are other good detectors available,
too. What’s important is that you have a
strategy for dealing with CO. Remember,
the life you save may be your own!
Max Trescott, EAA 531980, is an aviation author
and publisher, and was the 2008 National CFI of the
Year. For more of his articles, go to www.Max Trescott.com.
For a PDF of the DOT/FAA/AR-09/49 Detection and Prevention
of Carbon Monoxide Exposure in General Aviation Aircraft,
go to www.SportAviation.org.