PM₁₀ Air Sampling

The EPA began using a standard for concentrations of airborne particulate matter (PM) less than 10 micrometers in diameter (PM₁₀) in 1987 (40 CFR 50.6, 1996). Particles of this size can be inhaled deep 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 these particulates 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 Rexburg CMS and Blackfoot CMS, and one in Atomic City. Sampling of PM₁₀ is informational only as no chemical analyses are conducted for contaminants. A twenty-four hour sampling period is scheduled to run once every six days. Equipment and measurement problems nullified a number of samples from each location (six each from Atomic City and the Blackfoot CMS, and five from the Rexburg CMS). The maximum 24-hour concentration was 37.4 µg/m³ on February 12, 2002, in Rexburg. The average, maximum, and minimum results of the 24-hour samples are summarized in Table 1 below. None of the results exceeds the maximum 24-hour air quality standard established by EPA. Results for all PM₁₀ samples are listed in Table C-5, Appendix C.

Table 1           Summary of 24-hour PM₁₀ values.