What is the required temperature rating for ordinary hazard sprinklers?

Ordinary hazard sprinklers are designed to operate effectively in environments with a specific level of heat exposure. The required temperature rating for ordinary hazard sprinklers is 155°F (68°C). This temperature classification corresponds to the expected thermodynamic conditions in common occupancy types classified as ordinary hazards, such as warehouses or small manufacturing facilities.

The 155°F rating ensures that the sprinklers will activate in a timely manner during a fire event, thereby providing adequate suppression capabilities for settings where the risk of fire is intermediate, neither too low nor excessively high.

Other temperature ratings are designated for different categories of hazards—lower temperatures for light hazard applications and higher temperature ratings for extra or high hazard environments. These distinctions are crucial for ensuring that the fire protection system is tailored appropriately to the specific risks present in a facility.