Two types of sampling can be done:
- For point or channelized sources, sampling can be done using a lung made from neutral materials. Sampling is done using the “lung method,” recommended in standard EN 13725: the bag is filled by depressurizing the rigid enclosure in which it has been placed. This way there is no risk of the sample becoming contaminated by contact with the pumping system.
- For surface sources (compost windrows or settling ponds), odor samples are taken using a flow chamber (dynamic or static). This technique makes it possible to sample the gas actually emitted by a surface source without disturbing its natural flow.