How much vertical clearance should be maintained under a sprinkler head?

Maintaining an 18-inch vertical clearance under a sprinkler head is important to ensure effective functioning of the fire protection system. This clearance helps to prevent any potential interference with the spray pattern of the sprinkler, ensuring that the water is distributed evenly and effectively over the intended area. If objects are too close to the sprinkler head, it may impede the flow of water, leading to insufficient coverage during a fire event. This requirement is consistent with the standards set forth in fire safety codes, which emphasize the importance of unobstructed spray for maximum effectiveness in fire mitigation. Maintaining this distance helps to promote safety and minimize the risk of damage during a fire by allowing the sprinkler system to operate at peak performance.