Is there a requirement for the thickness of protection for ENT when passing through bored holes in wooden supports?

The requirement for the thickness of protection for Electrical Nonmetallic Tubing (ENT) when passing through bored holes in wooden supports is that it must be covered by at least 1.6 mm thick steel. This protection is mandated to ensure that the ENT is safeguarded from physical damage, which can occur due to external factors.

When ENT is installed, it must be adequately protected to prevent any potential wear or damage that could lead to electrical hazards. The use of a protective covering made of a specific thickness of steel, such as 1.6 mm, provides a reliable means of ensuring that the electrical system remains intact and safe over its lifespan. This thickness is specified to provide sufficient strength and durability, which helps maintain the integrity of the ENT in situations where the wood may be subjected to stress or degradation over time.

In contrast, other options suggest either no requirement for protection, complete coverage without specifying thickness, or protection only when the ENT is exposed, which do not comply with safety standards that are in place to mitigate risks associated with electrical installations.