When a raceway is run from the interior to the exterior of a building, what is required?

When a raceway transitions from the interior to the exterior of a building, sealing it with an approved material is necessary to protect against moisture ingress and to ensure that the internal environment remains secure. Sealing the raceway prevents water, pests, and other environmental factors from entering the building's interior, which could compromise electrical systems and overall safety.

The requirement for sealing is usually dictated by building codes and industry standards that seek to ensure the integrity and functionality of electrical systems. This is particularly important in areas where exposure to outdoor conditions can occur.

Different types of raceways may have specific materials or methods for sealing that are mandated by local codes or regulations. However, the core idea behind this requirement is to maintain a barrier between the external environment and internal systems to prevent potential hazards.

Other options may involve the type of conduit or seal used, but the fundamental requirement is indeed the necessity of sealing the raceway appropriately to protect the system.