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record the SFR (sampler’s seasonally adjusted set point flow rate in m3/min).
SFR = 1.13 [(Ps/Pa)(Ta/Ts)]
where: SFR = sampler’s seasonally adjusted set point flow rate, m3/min
1.13 = designed sampling flow rate of PM10 samplers, m3/min
Ps = seasonal average barometric pressure, mm Hg
Pa = actual ambient barometric pressure during calibration, mm Hg
Ts = seasonal average temperature, K
Ta = actual ambient temperature during calibration, K
SFR = 1.13 [(757/753)(294/291)]
SFR = 1.13 [(1.005312)(1.0103092)]
SFR = 1.13 [1.0156759]
SFR = 1.147 m3/min
To be more accurate when using an average temperature and barometric pressure, it is better to use a
daily, weekly, or monthly average instead of a seasonal average.
Then, calculate and record the SSP, sampler’s seasonally adjusted recorder set point.
SSP = [m * SFR + b] [Sqrt(Pa/Ta)]
where: SSP = sampler’s recorder set point, recorder response
m = slope of sampler from linear regression
SFR = sampler’s seasonally adjusted set point flow rate, m3/min
b = intercept of sampler from linear regression
Sqrt = square root
Pa = actual ambient barometric pressure during calibration, mm Hg
Ta = actual ambient temperature during calibration, K
SSP = [17.6685 * 1.147 + 8.9094] [Sqrt(753/294)]