Which type of fittings is permitted in concealed locations?

Threaded elbows, tees, and couplings are permitted in concealed locations because they provide a reliable and secure connection for propane gas lines. These fittings are usually made from durable materials that can withstand the pressures associated with gas systems and are designed to be leak-proof when properly installed. In concealed locations, where visibility and accessibility are limited, the strength and integrity of these fittings become especially important to ensure safe operation and reduce the risk of leaks.

The other types of fittings may not be suitable for concealed locations due to factors such as material limitations or potential for leakage. For instance, plastic fittings are generally not recommended for use in concealed spaces where they may be subject to impacts or temperature changes. Compression fittings, while useful in certain applications, can be less reliable over time and may be more prone to leaks if not maintained properly. Flexible fittings, although useful for accommodating movement and misalignment, are often not designed for permanent installations in concealed areas where they could be subject to wear or damage. Overall, the choice of fittings in concealed areas must prioritize safety, durability, and compliance with code requirements, which is met by using threaded elbows, tees, and couplings.