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Detect Carbon Monoxide


Calibration of Pocket CO is recommended at least yearly to ensure accurate readings, or whenever the accuracy of the reading is critical. Calibration can be done though KWJ’s TechCheck service, or if you wish to do your own calibrations, please contact us first to discuss.

KWJ TechCheck Service:

KWJ’s TechCheck service is an easy way to perform the recommended yearly calibration. For $79 plus s/h ($8.95 domestic, $30 international), this service includes a full inspection of your instrument, calibration and testing, new battery, firmware update, and new CO sensor element if needed.

Instruments can be sent to KWJ Engineering for a TechCheck through the mail. Just print out and complete a copy of the service form. Then place the completed form, along with your Pocket CO, in a padded envelope and mail to:

KWJ Engineering
Pocket CO TechCheck
8430 Central Avenue Suite C
Newark, CA. 94560

Please do not mail the manual, or any of the original packaging. Please remove anything attached to the keychain or clip. The TechCheck is usually completed within 5-7 business days after arrival.

For further information on battery replacement, calibration service, or repairs, please contact KWJ Engineering Inc:

Email: pocket_support@kwjengineering.com
Phone: (800) 472-6626

Attention owners of Model 100 and Model 200 instruments:

To calibrate your Model 100 or Model 200 instrument, or to replace the battery, contact KWJ Engineering for instructions and pricing information. (800) 472-6626

Or, take advantage of KWJ’s upgrade offer. For the discounted price of $105 + $8.95 s/h, you can upgrade to a Model 300. This new detector is as reliable as your current instrument, but has the advantage of a replaceable coin-cell battery. Just send your old instrument to KWJ along with this service form, and a check for $105 + $8.95 s/h. Credit cards can also be processed over the phone.

Caitlin Brondolo Foundation

Why to Buy Pocket CO

What our customers say

We are a volunteer first aid squad and like to keep the Pocket CO clipped to our blood pressure case. This way, every time that we enter a home or business to treat a patient, we run a quick test to assure that we are safe.

Anthony J. Pellegrino, Captain, Shrewsbury First Aid Squad, NewJersey

Last Wednesday I took off from Langley BC to Powell River and back to Langley in a Piper Cherokee for a dual cross country ride; this is a bit over two hours flight, and most of the way is along the Pacific coast. After I started the engine we heard some sort of beep in the cabin, so we looked at the instruments, checked cell phones, our headsets, everything seemed OK, plus none of us heard that kind of beep in a Cherokee before. It took us about a half hour of flight to figure out that the Pocket CO was beeping (was the first time using it, completely forgot I had it until my flight instructor asked me to check that “thing” hanging around my neck). When I read it, it showed 63ppm; so we closed the heaters, and opened all vents, until the reading dropped to 3ppm, that is a more “normal” figure. By now we were well above Vancouver, but because of the low reading we decided to keep going and not go back to Langley. Apparently the CO peaked to 90ppm (if I read the 12hrs log correctly), that was probably during our climb when we used full power. My flight instructor wanted to ground the airplane, but the end result was the school installed a new chemical indicator! The mechanics got a bit touchy, because the airplane just got back from a 100hrs check, they said there was no way we had any CO in the cabin, but I’ve seen the numbers, and I don’t really care what they say: I fly the airplane. I knew this little device could save my skin one day, I didn’t expect it so soon! I had a few more flights since then, with different airplanes, all show a very low CO number.

Ion, Canada, May 2010

Just wanted to let you know that I am one of your success stories. I purchased a Pocket CO monitor for use in my research. It came in handy one day when a new CO alarm in my home started to go off. Using the Pocket CO, I was able to determine that the CO alarm wasn’t faulty–we had CO in the house! We traced the source to a vent pipe that was never married to our hot water heater. I’m a big fan of your product which is inexpensive, portable, and very easy to use. It’s a great addition to home CO alarms, and I always take mine with me when I travel. Thanks!!

Eric L., Emergency Physician/Medical Toxicologist, Colorado, January 2010

I just bought the Pocket CO detector a few weeks ago for my airplane. While flying I noticed it get up to over 100 ppm. So, today I closely inspected the exhaust manifolds and found a hidden hole in the exhaust stack. I never would have known about it if I hadn’t bought Pocket CO! Thanks!

Doug M., Southern California, December 2009