What is the required frequency for testing the antifreeze solution in a sprinkler system?

The correct frequency for testing the antifreeze solution in a sprinkler system is annually. This requirement is in line with guidelines set forth in various fire protection standards, including those from the National Fire Protection Association (NFPA). Testing the antifreeze solution annually ensures that it maintains the appropriate concentration and efficacy to prevent freezing in the system.

Over time, antifreeze solutions can degrade due to environmental factors, which can compromise their effectiveness. Annual testing helps identify any significant dilution or changes in concentration that may occur, ensuring that the system remains reliable and effective in protecting against fire hazards in cold climates.

While options like monthly, quarterly, and biennially indicate different frequencies, they do not align with the established standards for antifreeze maintenance, which emphasize the importance of an annual check to ensure safety and compliance with fire protection regulations.