Thread Sealants:

Teflon or natural gas-rated pipe tape or pipe dope is acceptable for non-corrosive gases.  For corrosive gases, pipe tape is not recommended, unless the manufacturer specifies that it is rated for the gas being flowed through the meter. 

 

NOTE: When installing the device, ensure that excessive tape or dope does not fall into the meter, as this can damage sensors, plug sensor lines, prevent flow through the meter, and prevent the device from functioning properly.