Single-wall metal pipe shall NOT pass through which of the following?

Single-wall metal pipes are designed to transport propane and other gases; however, their use involves strict safety regulations. One key safety consideration is that these pipes should not pass through concealed spaces. Concealed spaces, such as walls, floors, and ceilings, are areas that are not readily accessible and can trap heat and gas in the event of a leak or failure. The risk associated with having single-wall metal pipes in these areas is significant because any leakage of propane could go unnoticed, posing a serious fire and explosion hazard.

In contrast, running single-wall metal pipe through cold spaces, open areas, or occupied areas may have different safety protocols or installation requirements that allow for better ventilation and detection of issues, reducing the risk compared to concealed spaces. Adequate spaces allow for easy inspection and maintenance, which are crucial to ensuring the safe operation of propane systems.