At what height must sprinklers be installed within rack storage?

• A. 25 Feet
• B. 15 Feet
• C. 30 Feet
• D. 40 Feet

Answer: (A)

In rack storage, sprinkler height is chosen to ensure the water from the heads can effectively reach the flames inside the densely packed shelves. If the heads are placed too high, the spray may have to travel through more obstruction and through hot, rising air, reducing reach and distribution effectiveness. If they’re placed too low, the water may not reach the upper levels of the racks or could be readily blocked by stored goods.

The 25-foot height represents a practical balance commonly used in warehouse rack configurations: high enough to cover multiple rack levels and dense packing, yet still within the spray and reach capabilities of standard sprinklers to control or suppress a fire in the goods. When storage heights exceed what standard ceiling sprinklers can adequately cover, designers often switch to specialized rack sprinklers or in-rack protection to maintain effective water distribution.