If you use a general purpose compressor to compress flammable Natural Gas, rather than the Class 1, Div 1 or 2 rated machines, you should expect some exciting results. Maybe not the first or second time you use it; but almost certainly eventually.
There is a very good reason the Natural Gas Industry is ONLY allowed to use electrical equipment rated for hazardous areas. It was an expensive and deadly learning curve for too many years.
Tiny leaks and arcing contacts, brush motors, etc don't mater much when compressing air. Natural Gas is another case.
We don't spend the extra money for no reason. And there is also a reason the electrical Hazardous Area Classification drawing are nearly always required to be stamped by a registered professional engineer.
He did have one episode when the timing chain cover was blown off a truck. I wouldn’t hestitate to use the setup provided explosion proof electrical fittings were used along with locating and isolating the compressor like the dynamite magazines that used to be very common.