Having supplied electrical equipment to the mining industry, I wrote a piece about Intrinsic Safety and gas meters for the old ‘Learn’ section. For anyone contemplating putting electricity in the vicinity of a gas meter, it might be worth tracking that down. [It’s under ‘Electricity Monitoring → Pulse Counting’]
And another word of caution: most equipment advertised as I.S. is actually only good for petrochemicals - the requirements for hydrogen or methane (in my case) are much more stringent.