What requirement exists for the installation of cables through bored holes in joists and rafters?

The requirement that holes must be at least 1 1/4 inches from the edge of joists and rafters is crucial for maintaining the structural integrity of the wood. By following this guideline, you reduce the risk of compromising the joist or rafter's strength, which could potentially lead to structural failures.

When holes are drilled too close to the edge, it increases the likelihood of splitting and can weaken the member significantly. The 1 1/4 inch distance acts as a safeguard, ensuring that the structural member maintains enough material around the hole to support loads safely.

In a well-constructed installation, adhering to these specifications not only enhances safety but aligns with building codes and standards that govern electrical and structural work. This is important for compliance and ensures durability in the long run. Other options may overlook these crucial safety and structural considerations, making them less appropriate.