What is the minimum total combined hose stream allowance required for a hydraulically calculated sprinkler system in an extra hazard area?

In a hydraulically calculated sprinkler system serving an extra hazard area, the minimum total combined hose stream allowance is set at 500 gallons per minute (gpm). This requirement is based on the recognition that extra hazard areas present a higher level of risk due to the potential for greater fire loads and more significant hazards, necessitating a more robust response from the fire protection system.

The 500 gpm figure is significant as it ensures that the system can adequately support the demands placed during a major fire scenario, allowing both the sprinkler system and fire department hoses to work effectively together. This allowance provides a buffer for extra water flow that might be necessary to control or extinguish a fire more effectively in environments where combustible materials or hazardous conditions are present.

By adhering to this minimum requirement, fire safety professionals ensure that the sprinkler system is appropriately equipped to handle the unique challenges posed in high-risk areas, enhancing overall fire protection and safety.