Which of the following best describes the testing frequency for a dry standpipe system without a backflow preventer?

The testing frequency for a dry standpipe system without a backflow preventer is best described as annually. This is in accordance with the National Fire Protection Association (NFPA) regulations, which outline the requirements for the inspection, testing, and maintenance of standpipe systems.

Annually testing is essential for ensuring that the dry standpipe system is operational, as it helps identify any potential issues that might interfere with its use during an emergency. This frequency allows for a thorough assessment of the system, including checks for obstructions, valve operation, and structural integrity, which are crucial for fire safety.

Options such as quarterly or daily suggest a testing frequency that is typically associated with other systems or components that might require more frequent monitoring due to their operational nature or critical role in safety. Bimonthly does not align with industry standards for dry standpipe systems either. Thus, the annual testing requirement aligns with established protocols aimed at maintaining the reliability and safety of fire protection systems.