A dry pipe system with a QOD is permitted to hold how many gallons?

A dry pipe system with a Quick Opening Device (QOD) is designed to provide a rapid release of water to the sprinkler system in case of a fire while preventing the water from entering the system during non-activation conditions. According to codes and standards governing sprinkler systems, particularly those from the National Fire Protection Association (NFPA), a dry pipe system is limited in the amount of water it can hold.

The correct answer, which states that a dry pipe system with a QOD is permitted to hold 750 gallons, aligns with the NFPA guidelines regarding the volume limitations for these types of systems. This limitation is necessary to ensure that the system is effective and responsive in emergency situations, as larger volumes could lead to increased system lag time due to the longer time it would take to discharge water.

This specific volume restriction allows for a balance between adequate water storage for fire protection and operational efficiency, making it a critical aspect of wet pipe systems equipped with QOD. Other options exceeding this volume could compromise the fast activation feature that the QOD is designed to facilitate.