See the NFPA (National Fire Protection Association) and the Copper Development Association (CDA)
Normally this would come under the auspices of a licensed master plumber
No it will not poison you. Copper piping is used extensively in Medical Gas applications. "TYPE L" signifies the wall thickness of the piping.
Piping material used for forming gas would be 316L stainless steel.
Black iron pipe is used for gas installations but ONLY if the piping is indoors. Outdoor gas piping is usually done in galvanized pipe. Steam is also piped with black pipe, fire sprinkler and standpipe systems also use black pipe.
I use schedule 40 for natural gas BUT if your talking medical Gases then look up the NFPA 54 or contact the CDA and your local codes
Galvanized piping or painted depending on local codes and type of fuel (gas) NO drip legs where the piping is subject to freeze ups
To get the electricity from where it came from to where it is going, Just like water piping, gas piping, sewer piping, etc.
Gas piping must be bond to the appliance it serves.
The purpose of a drip leg in the gas piping is used as a device to capture dirt and debris from entering the furnace.
Most codes do not allow Galvanized piping/fittings on gas piping. I have used galvanized pipe/fittings on exterior gas piping before in the state of Michigan but other states do not allows this. Check with your local code authorities.
Natural gas can leave a residue in piping due to impurities in the gas such as sulfur compounds or moisture that can react with the metal of the piping or form deposits over time. These residues can accumulate and clog the piping, leading to reduced flow efficiency and potentially causing operational issues. Regular maintenance and cleaning of the piping can help prevent the buildup of residues.
i dunna??
As far as I know, for underground piping use plastic, for above ground steel or copper. That is the practice in the UK, but I don't know about the US. I would be surprised if it is different. We did have underground steel pipes but these are now being replaced with plastic and all new is plastic (underground)