Journeyman Mechanical Practice Test

The minimum thickness required for steel, stainless steel, and wrought-iron gas pipe is specified using a classification system known as “schedule.” This system establishes various wall thicknesses to cater to different pressure and application requirements. Schedule 10 pipe is used for low-pressure applications and has a thinner wall compared to other schedules.

In contrast, options like Schedule 40 denote a thicker wall pipe typically used for standard pressure applications and is not the minimum thickness for these materials. Type A and Heavy Duty do not pertain specifically to the standardized pipe thickness measurements that are generally recognized. Therefore, the reference to Schedule 10 accurately reflects the minimum thickness for gas piping made from steel, stainless steel, and wrought iron.