Standard response sprinklers must be replaced or tested after how many years of service?

Standard response sprinklers are typically designed to have a service life of 50 years, which is why the correct answer is 50 years. This is based on industry standards and guidelines set by organizations such as the National Fire Protection Association (NFPA) and manufacturers' recommendations. The longevity of these components is influenced by factors such as material degradation, environmental conditions, and the inherent reliability of the devices. After 50 years, it is prudent to ensure the sprinklers are still functioning effectively and comply with safety regulations, necessitating testing or replacement.

In contrast, the other options suggest timeframes that are either too short or exceed expected longevity. For instance, 10 years and 20 years are well below the expected lifespan, while 75 years would imply an impractical level of durability beyond standard expectations. Hence, 50 years is recognized as the appropriate threshold for standard response sprinklers, ensuring safety and operational efficiency within fire protection systems.