All fire hydrants shall be opened fully and flowed until all foreign material has cleared or for a minimum of 1 minute at what intervals?

The requirement to fully open and flow fire hydrants until all foreign material has cleared, or for a minimum of one minute, is established to ensure that fire hydrants are functioning correctly and that any sediment or debris that may have accumulated within the water system is flushed out. Conducting this operation annually helps maintain the reliability and functionality of the hydrants, which is crucial during emergencies.

The annual interval allows enough time for any potentially detrimental materials to be removed while balancing maintenance needs with practical scheduling. This ensures that the hydrants remain in optimal condition to provide adequate water supply during crucial firefighting operations. Regular testing at this frequency can also help identify any issues with the hydrants early on, facilitating prompt repairs and enhancing public safety.