What should the ends of conduit stubs be to prevent dirt and moisture from entering?

To effectively prevent dirt and moisture from entering conduit stubs, they should be capped. Capping the ends of conduits provides a solid barrier that protects against environmental factors that could compromise the integrity of the wiring contained within. Moisture can lead to corrosion or electrical shorts, while dirt can cause blockages and interference with the electrical systems. Capped ends ensure that the internal wiring remains clean, dry, and functional over time, adhering to safety standards and extending the lifespan of the electrical installation.

While options like having the ends curved might seem beneficial for drainage, they do not offer the protection that capping provides. An open end would expose the conduit to all sorts of contaminants, while a coating may not create a complete seal necessary to keep out moisture and debris. Thus, capping is the most effective solution for this scenario.