§ 42-9. Types of materials.

A. 

Standard full-weight wrought iron, steel or brass pipe with substantial fittings or approved brass or copper tubing with approved fittings shall be used and shall be carefully protected against mechanical injury in a manner satisfactory to authorities having jurisdiction. In all piping systems proper allowance shall be made for expansion and contraction, jarring and vibration.

B. 

All piping shall be separated from electric wiring not enclosed in approved conduit raceways or armored cable, by some continuous and firmly fixed nonconductor creating a permanent separation as provided in the National Electrical Code.

C. 

Approved brass or copper tubing, where permitted by authorities having jurisdiction, shall have a wall thickness of not less than one-sixteenth-inch for small sizes and correspondingly heavier where necessary.