How deep should fire service mains be buried in areas subject to freezing?

The depth at which fire service mains should be buried in areas subject to freezing is critical to ensure that the pipes do not freeze and remain operational during cold weather. According to NFPA 24 guidelines, a depth of 42 inches is recommended to provide sufficient protection against freeze damage. This depth is generally determined based on historical frost line data, which indicates how deep the ground typically freezes in a given region.

By burying the fire service mains at 42 inches, it helps to ensure that the water within the pipes remains above the freezing point, thereby maintaining the integrity of the fire protection system and ensuring availability when needed. This depth is a commonly accepted standard that balances installation practicality with the need for protection against frost-related issues.

Understanding the frost line in specific geographic areas and adhering to the recommended burial depths enhances not only the resilience of fire service mains but also ensures compliance with safety regulations.