What is the maximum change in direction permitted in any plane lengths of straight, rigid conduit without the use of bends?

The maximum change in direction permitted in straight, rigid conduit without the use of bends is indeed 5 degrees. This limit ensures that the conduit maintains structural integrity and facilitates easier installation of wiring while minimizing potential stress on the conduit. Maintaining proper angles is crucial to ensure ease of wire pulling and to prevent damage to the cable insulation, which can occur if the conduit is bent excessively or inappropriately.

Larger angles, such as 10, 15, or 20 degrees, would necessitate the use of bends to safely change the direction of the conduit. These angles could create tighter turns, making it difficult to pull electrical conductors through the conduit without risking damage or kinks. Therefore, following the 5-degree guideline is essential for adhering to safety standards and ensuring the longevity of the installation.