What type of conduit is described for allowing certain installations without support?

The type of conduit that allows certain installations without support is Intermediate Metal Conduit (IMC). IMC is recognized for its strength and light weight, making it a suitable option for applications where a conduit is needed but support might be impractical to install.

What sets IMC apart is its structural resilience, allowing it to be used in a variety of settings while requiring less frequent support compared to some other conduit types. This characteristic can be particularly advantageous in tight spaces or locations where access might be limited.

In contrast, while the other types of conduits—such as flexible conduit, rigid PVC conduit, and EMT conduit—have their own unique applications and benefits, they typically do not share the same allowance regarding the spacing between supports as IMC. Each type has specified support requirements detailed in the National Electrical Code (NEC), which dictate how often a conduit must be secured to ensure safety and proper function.