A. Piping used for flammable liquids shall be standard full weight, wrought iron, steel or brass pipe or approved copper tubing, for working pressures in excess of one hundred (100) pounds per square inch extra heavy fittings shall be used. No pipe or tubing less than one-half inch (1/2") internal diameter shall be used. Outside piping shall be protected against mechanical injury.
B. Piping carrying class I and II liquids, unless without joint or connections shall not extend through any room which contains any open light or fire. (1961 Code)