Strike termination devices shall be placed at intervals not exceeding ____________ on ridges or pitched roofs.

The correct interval for placing strike termination devices on ridges or pitched roofs is 20 feet. This requirement is established to ensure that adequate protection is provided against lightning strikes, which is critical for safety in structures that may be susceptible to such events. By positioning these devices at 20-foot intervals, it helps create a reliable and effective system for lightning protection, ensuring that the area is well-covered and reducing the risk of damage or injury.

The choice of 20 feet strikes a balance between effectiveness and practicality, allowing for sufficient coverage without becoming cumbersome to install or maintain. This standard also aligns with industry practices that have emerged from research into lightning behavior and the performance of strike termination systems.