3. Measurement methods

3.1 Mass measurement

• Weighing

  Once the filter has been conditioned at constant temperature and humidity, it is usually weighed to determine the amount of TSP (Total Suspended Particulate) deposited on the filter. This is the cheapest and quickest method, but it is not without its hazards. Between conditioning in the laboratory, sampling in the field and weighing back in the laboratory, losses can be significant and this method is not very accurate.

• Radiation measurement $\text{β}$

  The principle of radiation measurement is based on the fact that the number of particles β transmitted...