Ground gas and volatile organic compound (VOC) monitoring

A F Howland Associates undertake ground gas investigations in accordance with CIRIA C665 and NHBC recommendations.
We utilise fully calibrated MiniRAE 2000 photo-ionisation detector (PID) for VOC monitoring and Geotechnical Instruments GA2000 for ground gas monitoring.  The GA2000 records oxygen, carbon monoxide, carbon dioxide, hydrogen sulphide and methane in addition to flow via a separate flow pod attachment.  The PID is best applied for screening of soils and waters on-site via head space testing of samples or detection of leaking underground fuel storage tanks through monitoring gas standpipe installations.

MiniRAE 2000 PID	GA2000 gas monitor

The preliminary conceptual model formulated by the Phase I study or the initial stages of the ground gas risk assessment will determine the likely sources of ground gas (landfill, peat, coal mine or fill strata derived).  This allows a site specific gas monitoring regime to be designed for the site with the gas monitoring period determined by the anticipated source of ground gas.

The results of the ground gas investigation are assessed using CIRIA C665 and NHBC guidance and the appropriate mitigation measures recommended by AFHA