We are sometimes asked if Aircuity senses Formaldehyde. While Aircuity does not sense it directly, TVOC’s can typically be used as a proxy for formaldehyde since it often tracks with the formaldehyde levels in commercial buildings. We also don’t sense formaldehyde since we have found that commercial formaldehyde sensors that are on the market do not have anything close to the accuracy and sensitivity required at the very low levels of formaldehyde that are necessary to be measured. For example, the WELL Building Standard has required a basic prerequisite for formaldehyde to be less than 27 ppb with an enhanced requirement to be less than 13 ppb. They require monitors to be accurate to at least 5 ppb. However, commercial formaldehyde sensors typically cannot read accurately below 30 to 50 ppb, typically have accuracies no better than +- 50 ppb, and often have significant cross sensitivities particularly at these very low levels.
If clients want to truly measure formaldehyde accurately then they would need to take air samples periodically and have them tested in a lab with a mass spectrometer or GC (gas chromatograph). Doing anything else will yield almost random numbers unrelated to actual concentrations at least at these low levels of interest.