Any infromation on guidelines or standard for fire prevention during gas drilling? We have a case where casing and drilling for piling works required on a former landfill site where they have encountered methane gas. Part of the drilling for piling works is dry process. While methane within the landfill area may be too concengtrated (i.e. above the UEL) but as it comes out the concentration may be in the flammable range. The potential ignition sources are metal to metal and metal and rock friction may produce spark during dry drilling works. I will appreciate any advise regarding relevant guidelines or standards and or sharing of your expereince with similar issues?