So I Invented Filter Check Gas
If you can't trust your Hazardous Gas Detector, what can you trust?
I zeroed this monitor. I calibrated the CO sensor. Everything working perfectly. According to the monitor.
Then I used it an environment with other gases present and no carbon monoxide whatsoever. Guess what? It gave high carbon monoxide reading.
No CO present, yet it read high CO. According to the manufacturer, it was not sensitive to these other gases. What they didn't say was that the CO sensor was sensitive to these other gases, but that they had a carbon filter in place to absorb them before they got to the sensor.
When that carbon filter is saturated, it doesn't absorb the interferent gases, and they go straight through and give you either falsely high or falsely low readings. Not good. Not good at all.
So how do you know if your sensor's filter is no good?
I invented a family of gas mixtures to do just that. We call it Filter Check Gas. Run it to your monitor or detector and it will tell you instantly if the carbon filter is still working or not. The first Filter Check Gas is for electochemical CO detectors. The rest of the Filter Check Gases for other sensors will be released in the next two months.
They're for sale at Ideal Gases. I use them myself now because I need my CO detector to tell me the truth, and it can't do that if its carbon filter is compromised.