Increasing Importance of Ground Gas Assessments & Membrane Verification

Ground gases can be produced from a variety of natural sources including coal, peat, alluvial deposits and rock (Radon), plus a range of man-made sources such as landfills, in-filled ponds, made ground and spillages of fuel and volatile organic compounds (VOCs).

The impact of ground gases on development projects has become increasingly important in recent years primarily because of the need to build on brownfield sites. By definition, brownfield sites have previously been developed on and may therefore contain landfill, contaminants, and other industrial waste liable to produce ground gases.

Legislation requires developers to assess the risk of ground gases, take protective measures, and have these measures independently inspected and verified. At GRM we specialise in both the initial assessment of ground gasses and the inspection, verification and validation of protective gas membranes. Our verification service is 100% independent of the membrane manufacturer, installer and client.

One recent example involved a housing development site in Nottinghamshire. The potential for ground gasses had been identified at the assessment stage, and protective measures had been designed and installed. GRM were then instructed to undertake the inspection, verification and validation phase.

GRM was a founding member of the British Verification Council ( which was established in 2018 by industry professionals committed to raising standards in ground gas verification. One of our company directors currently sits on the BVC Board. The team is led by Siobhan Jackson, Principal Geo-Environmental Scientist at GRM and a qualified Chartered Environmentalist. She leads four dedicated inspectors who have all been through the CLAIRE Verification of Gas Protection Systems Training Course which we discussed in a previous post: Gas Membrane Verification Training.

If you have any development projects that need a ground gas assessment or membrane validation, then please get in touch to find out how we can help save both time and costs. Please contact Siobhan directly via email ( or call our head office on 01283 551249.