What is the testing interval for dry-type sprinklers after they have been in service for 50 years and passed their previous test?

The testing interval for dry-type sprinklers after they have been in service for 50 years, assuming they have successfully passed their previous tests, is indeed 5 years. This is rooted in the need to ensure the reliability and effectiveness of sprinkler systems that have been in operation for several decades. As materials age, they may become more susceptible to wear, corrosion, or other forms of degradation that can compromise their performance during a fire event.

Regular testing helps to detect any potential issues that may arise over time, ensuring that the system remains in optimal working condition. The 5-year interval reflects a balance between maintaining safety standards and acknowledging the longevity of the system, as it allows for regular assessments without being excessively burdensome. This requirement aligns with industry standards that prioritize both functionality and safety for older systems.