Qa = average flow rate at ambient conditions, m3/min;
Pav = average barometric pressure during the sampling period or average barometric
pressure for the sampling site, kPa (or mm Hg);
Tav = average ambient temperature during the sampling period or seasonal average
ambient temperature for the sampling site, K;
Tstd = standard temperature, defined as 298K;
Pstd = standard pressure, defined as 101.3kPa (or 760 mm Hg).
11.2 Calculate the total volume of air sampled as:
Vstd = Qstd * T
Vstd = total air sampled in standard volume units, std m3;
T = sampling time, min.
11.3 Calculate the PM10 concentration as:
PM10 = (Wf - Wi) * 106/Vstd
PM10 = mass concentration of PM10 micro-g/std m3
Wf, Wi = final and initial weights of filter collecting PM10 particles, g;
106 = conversion of g to micro-g.
Note: If more than one size fraction in the PM10 size range is collected by the
sampler, the sum of the net weight gain by each collection filter
[Summation (Wf-Wi)] is used to calculate the PM10 mass concentration.