scope:

This document sets out a method for the continuous determination of PM_2.5 in ambient air using a tapered element oscillating microbalance (TEOM) monitor incorporating a filter dynamic measurement system (FDMS) unit.

NOTE PM_2.5 has been statistically associated with certain human health end points, including daily mortality, hospital admissions and exacerbation of asthma. PM_2.5 emission sources include industrial processes, fuel combustion, burning of vegetation, incineration and natural causes such as windblown dust and salt laden air. Combustion processes tend to contribute more PM_2.5 than non-combustion sources. Important anthropogenic sources include domestic wood heaters and motor vehicles (especially diesel fuelled vehicles).

The method can provide a measure of mean particle concentration over periods from 1 h to 24 h. The rolling 1 h mean is updated every 6 min, whereas the rolling 24 h mean mass concentration is updated every 60 min on the hour. Results are normally reported as 24 h, time-integrated mean values. PM₁₀ and PM_10-2.5 may also be measured simultaneously with PM_2.5 if a dichotomous instrument is used.