What precaution should be taken when running conductors vertically?

When running conductors vertically, employing proper securing methods is crucial to ensure the safety and integrity of the installation. This involves using appropriate fasteners and supports to maintain the position of the conductors and prevent them from sagging or moving, which could lead to damage or potential safety hazards. Proper securing minimizes the risk of physical damage from impact or environmental factors and also helps to mitigate issues such as excessive bending or stress on the conductors, which can affect their performance and longevity.

The other options do not align with best practices or NEC guidelines for vertical conductor installation. For instance, there is no specific requirement for conductors to be placed a certain distance apart vertically, nor is there a restriction limiting installation to only new buildings. Additionally, overhead supports are often necessary depending on the specific application and environment in which the conductors are installed.