- Dr. Arindam Bhadra

Preventive maintenance (PM) is the regular and routine maintenance of equipment and assets in order to keep them running and prevent any costly unplanned downtime from unexpected equipment failure. Testing, servicing, calibration, inspection, adjustment, alignment, and installation are the seven elements of a preventive maintenance plan.

Regular maintenance and inspection of fire sprinkler systems are crucial to ensure their proper function in the event of a fire emergency. 

According to NFPA 13 - 2022 edition (28.5.2.1.1), Branch lines shall not exceed eight sprinklers on either side of a cross main and shall be sized in accordance with light and ordinary hazard occupancies.

Where more than eight sprinklers on a branch line are necessary, lines shall be permitted to be increased to nine sprinklers by making the two end lengths 1 in. and 11∕4 in. , respectively, and the sizes thereafter standard.

Ten sprinklers shall be permitted to be placed on a branch line, making the two end lengths 1 in. and 11∕4 in., respectively, and feeding the tenth sprinkler by a 21∕2 in. pipe.

The distance between sprinkler deflector and the ceiling shall be (1 in) minimum and (12 in) maximum throughout the area of coverage of the sprinkler.

This guide provides step-by-step instructions on how to check your fire sprinkler system effectively.

1. Check Water Supply:

Verify that the water supply to the fire sprinkler system is turned on and that the main control valve is fully open.

Monitor the water pressure gauge to ensure that it indicates adequate pressure within the system.

Inspect any water storage tanks, fire pumps, or pressure-reducing valves for proper operation.

2. Conduct Flow Tests:

Perform flow tests on selected sprinkler heads to ensure they activate and discharge water as intended.

Use a flow test valve or flow meter to measure the flow rate from individual sprinkler heads.

Compare the observed flow rates with the system's design specifications to identify any deviations or irregularities.

3. Visual Inspection:

Start by visually inspecting all components of the fire sprinkler system, including sprinkler heads, pipes, fittings, valves, and alarm devices.

Look for signs of damage, corrosion, leaks, or obstruction that may affect the system's performance.

Ensure that there are no obstructions blocking the sprinkler heads and that they are free from dust or debris.

4. Test Alarm Systems:

Test the functionality of alarm devices, including water flow alarms, pressure switches, and supervisory signal devices.

Activate the alarm system manually or simulate a flow condition to trigger alarms and verify their proper operation.

Ensure that alarm signals are transmitted to the building's fire alarm panel or monitoring service as required.

5. Inspect Control Valves:

Check all control valves, including main control valves, zone control valves, and test valves, for proper positioning and operation.

Exercise control valves periodically to prevent them from seizing or becoming stuck due to lack of use.

Verify that valve tamper switches or supervisory switches are functioning correctly.

6. Document Findings:

Maintain detailed records of all inspection and testing activities performed on the fire sprinkler system.

Document any deficiencies, repairs, or corrective actions taken during the inspection process.

Keep inspection records readily accessible for review by building owners, fire officials, or insurance representatives.

How to Check a Fire Sprinkler System

1. Review System Documentation:

•  Start by reviewing the system documentation, including the original design drawings, hydraulic calculations, and maintenance records. Understanding the system layout and components will help guide the inspection process.

2. Inspect Sprinkler Heads:

•  Check each sprinkler head for proper orientation, alignment, and clearance. Ensure that there are no obstructions, such as storage shelves or decorations, blocking the spray pattern.

•  Look for signs of physical damage, corrosion, or paint buildup on the sprinkler heads, which can affect their operation.

3. Examine Piping and Fittings:

•  Inspect all piping and fittings for leaks, corrosion, or signs of deterioration. Pay close attention to areas where pipes pass through walls, ceilings, or floors, as these are common locations for leaks to develop.

•  Verify that pipe hangers and supports are secure and properly spaced to prevent sagging or misalignment.

4. Check Valves and Water Flow Devices:

•  Test all control valves, including main control valves, zone control valves, and alarm valves, to ensure they open and close properly.

•  Verify that water flow devices, such as water flow switches or meters, are functioning correctly by simulating a flow condition and observing the response.

5. Test Alarm Systems:

•  Activate the fire alarm system to ensure that it triggers audible and visual alarms throughout the building.

•  Test supervisory signal devices, such as tamper switches and low air pressure switches, to ensure they transmit alarm signals to the monitoring station.

6. Verify Water Supply:

•  Check the status of the water supply, including the availability of water sources such as municipal water mains, water storage tanks, or fire pumps.

•  Monitor water pressure and flow rates to ensure they meet the system's design requirements and local fire code regulations.

7. Perform Flow Tests:

•  Conduct flow tests on selected sprinkler heads to verify that they activate and discharge water at the expected flow rates.

•  Use calibrated flow meters or flow test kits to measure and record the flow rates from individual sprinkler heads.

8. Review System Labels and Signage:

•  Ensure that all system components are properly labeled and identified, including control valves, alarm devices, and sprinkler zones.

•  Check for missing or illegible signage and replace as necessary to facilitate quick identification in an emergency.

9. Document Findings and Recommendations:

•  Document all inspection findings, including any deficiencies or areas requiring corrective action.

•  Provide recommendations for repairs or upgrades based on industry best practices, code requirements, and the system's current condition.

10. Schedule Regular Maintenance:

•  Establish a schedule for regular maintenance and testing of the fire sprinkler system, in accordance with manufacturer recommendations and regulatory requirements.

•  Ensure that maintenance activities are performed by qualified technicians trained in fire protection systems and equipment.

Regular checks and maintenance of fire sprinkler systems are essential to ensure their reliability and effectiveness in protecting life and property from fire hazards. By following these steps and conducting thorough inspections, building owners and facility managers can identify potential issues early and take proactive measures to keep their fire sprinkler systems in optimal condition.

The SPRINKLER FIRE SAFTEY AWARENESS AND WELFARE FOUNDATION was founded in 2022 at India by a group of eminent Security Safety & Automation professionals. Anyone can contacts them to provide training or consulting about Fire safety.

(This "Expert Talk" Published in June 2024 Edition)