What condition must be met by conduits passing through hazardous locations without requiring seals?

The correct choice highlights that conduits can pass through hazardous locations without requiring seals if they have unbroken conduit ends in unclassified locations. This condition is significant because it allows for the physical protection of electrical conductors while preventing the escalation of hazardous conditions within a confined space. Maintaining unbroken conduit ends ensures that no gaps exist where flammable gases, vapors, or dust could enter, thus reducing the risk of ignition sources from wiring within the conduit.

Having unbroken ends means that the continuation of the conduit system effectively isolates the electrical elements from any potential hazardous environment. It is vital in ensuring that the integrity of the electrical installation is maintained and that any potential harmful substances remain outside of the electrical system.

Other factors are relevant to conduit installation, including avoiding couplings or excessive fittings in certain contexts, but those may not qualify for the exemption from sealing requirements. The diameter of the conduit can also vary based on specific applications and not necessarily dictate sealing needs based on its size alone. Each of these details underpins the critical safety measures necessary for working in hazardous locations, primarily focusing on preventing any pathways for ignition from entering those areas.