PM₁₀ Air Sampling

The EPA began using a standard for concentrations of airborne particulate matter (PM) less than 10 micrometers in diameter in 1987 (40 CFR 50.6).  Particles of this size can reach deeply into the lungs and are considered to be responsible for most of the adverse health effects associated with airborne particulate pollution.  The air quality standards for fine particulates, generally referred to as PM₁₀, are an annual average of 50 µg/m³, with a maximum 24-hour concentration of 150 µg/m³.

The ESER Program operates three PM₁₀ samplers, one each at the Community Monitoring Stations (CMS) in Rexburg and Blackfoot, and one in Atomic City.  Sampling of PM₁₀ is informational as no analyses are conducted for contaminants.  Twenty-four hour sampling periods were scheduled to run once every six days.  Equipment problems nullified the samples for October 9 in Atomic City and for October 3 and 27, and December 8 from Rexburg.  A power failure nullified the December 2 sample from Blackfoot.  A total of 14 samples each were collected from Blackfoot and Atomic City with a total of 12 collected from Rexburg.  PM₁₀ concentrations were well below all health standard levels for all samples.  The maximum 24-hour concentration was 77.8 µg/m³ on November 8, 2001, in Blackfoot.  The average, maximum, and minimum results of the 24-hour samples are shown are shown in Table 1.  Results for all PM₁₀ samples are listed in Table C-5, Appendix C.

TABLE 1.Summary of 24-hour PM₁₀ values (mg/m³).