2B-Technologies - Personal Air Monitor (PAM)

The PAM also outputs values for PM10, but as discussed on our AQSensors vs. Instruments page, PM10 is not accurately measured by sensors because of the difficulty of sampling large particles without loss due to impaction.  PM2.5 and PM1 are the most important size ranges, however, because only particles smaller than 2.5 µm enter the lungs where they have adverse health effects such as triggering asthma attacks.  All three pollutants measured are products of combustion, making the PAM ideal for tracking air pollution arising from automobile exhaust, power plants, forest fires and other combustion sources.  Carbon dioxide is of interest outdoors because it is the principal greenhouse gas responsible for global warming, but also indoors because CO2 builds up inside buildings due to human respiration and affects human cognitive abilities at concentrations above about 1,000 ppm.

Many companies sell sensor packages that measure additional air pollutants such as NO, NO2, SO2 and H2S using electrochemical sensors.  None of these species are reliably measured by sensors without very frequent multivariate calibrations due to a combination of factors including 1) their very low ambient concentrations, 2) sensor calibration drift and 3) cross sensitivities.  As new sensors become available that achieve adequate sensitivity and accuracy to be useful for air pollution monitoring, we will make them available on the PAM. Note that of the species measure by the PAM, PM2.5 and CO, are designated by the US Environmental Protection Agency as Criteria Pollutants.