Sample storage and preparation for analysis

Soil-gas samples collected on adsorbents should be stored in the same manner as soil samples to prevent drying out and loss of sulphur compounds. Samples collected in solutions or on filters are generally analysed immediately or shortly after collection. 

Soil and molecular sieve adsorbent samples must be degassed for analysis. Useful analytical results may be obtained by simply heating the sample in an air-tight system and driving the evolved gases into the gas chromatograph. However, this technique does not yield very reproducible results, a limitation which is sometimes minimised by the analysis of several replicate samples. 

---