Which systems require regular maintenance according to NFPA standards?

The correct answer emphasizes that all sprinkler systems require regular maintenance according to NFPA (National Fire Protection Association) standards. These standards are designed to ensure the reliability and functionality of fire protection systems, which are crucial for safeguarding lives and property in the event of a fire.

Regular maintenance includes inspection, testing, and maintenance (ITM) procedures that help to identify any issues that may impair the system's operation. This can involve checking the water supply, verifying that control valves are accessible and operational, inspecting sprinkler head conditions, and testing the alarm and notification systems. The NFPA provides detailed guidelines within their codes, particularly NFPA 25, to specify the frequency and type of maintenance activities needed for different components of sprinkler systems.

While residential water supply systems, private fire service mains, and portable fire extinguishers each have their own maintenance requirements, they do not fall under the same rigorous and comprehensive maintenance protocol that NFPA establishes for all sprinkler systems. Hence, the emphasis on the importance of regular maintenance for sprinkler systems ensures that these life-saving devices function as intended when needed.