Published March 2025

The occurrence of ground gas is well documented within all drilling sectors, however, the potential for encountering a pressurised gas pocket within the land drilling sector whilst not common or well documented is not an unknown hazard. The geographical locations, geological setting and likely sources of pressurised gas are reasonably foreseeable as long as the works involve a competent ground engineering specialist with the relevant experience to assess the risk.

Managing the risk of encountering pressurised gas during drilling must form part of a robust risk assessment process for all sites and where the hazard is identified, suitable and sufficient control measures and emergency response must be implemented and all site staff briefed and trained.

This guidance provides information to aid ground engineering specialists in the risk assessment process.