Sprinkler systems control or put out fires automatically, but only if water can reach the heads and the heads are free to work. Inspection, testing and maintenance on a set schedule keeps valves open, gauges normal, heads clear and pipes free of corrosion and ice. The fire code makes owners responsible for having this done and for managing any time the system is out of service.
The rules
The National Building Code of Canada and the provincial building codes decide where sprinklers are required, with installation generally to NFPA 13 or the related residential standards. Once a building is occupied, the National Fire Code of Canada and the provincial fire codes in Alberta, BC and Ontario require water-based fire protection systems to be inspected, tested and maintained, generally by reference to NFPA 25. Check which edition your provincial code references, and any requirements from your local fire authority or insurer.
Types of systems
| Type | How it works | Where it is used |
|---|---|---|
| Wet pipe | Pipes are always full of water; heads open individually from heat | Heated buildings; the most common type |
| Dry pipe | Pipes hold pressurized air; when a head opens, air escapes and a dry pipe valve lets water in | Unheated spaces such as parkades, loading docks and attics |
| Pre-action | Pipes are dry until a separate detection system releases water; heads still need to open | Data centres, archives and other spaces where accidental discharge is costly |
| Deluge | All heads are open; a detection system releases water through all of them at once | Special hazards, such as some industrial processes |
What gets inspected and tested
Frequent checks
Some items are checked weekly or monthly, often by trained building staff:
- Control valves open and sealed, locked or electrically supervised
- Gauges on wet, dry and pre-action systems showing normal pressures
- Dry pipe and pre-action valve rooms heated and the valves in normal condition
- Fire department connections visible, accessible, capped and undamaged
- Alarm devices free of physical damage
- Fire pump running conditions and room temperature, where there is a fire pump
Periodic tests by qualified technicians
- Waterflow alarm tests, confirming the alarm sounds and reaches the monitoring station
- Main drain tests, which compare water supply pressure with previous results
- Valve supervisory switch tests
- Dry pipe valve trip tests and quick-opening device tests on the required schedule
- Fire pump flow tests and regular run tests
- Antifreeze solution testing in antifreeze systems
- Periodic internal inspection of piping for corrosion and obstructions
- Testing or replacing sample sprinkler heads after a set number of years in service
Sprinkler heads
Heads must be able to sense heat and spray water across the area they protect. Look for:
- Paint, corrosion, dust or grease on heads, which can delay or prevent operation
- Damaged, leaking or missing heads, or missing escutcheons
- Storage, shelving, signs or new walls blocking spray patterns
- Required clearance kept below heads, especially in storage areas
- Heads of the wrong type or temperature rating installed during repairs
- A stock of spare heads and the correct wrench on site
Winter and dry systems. Water in a dry pipe system collects at low points and can freeze and burst pipes. Drain low point drains (drum drips) regularly through the cold season, and keep valve rooms and wet pipe areas heated. A frozen pipe can leave a whole zone unprotected.
Impairments
An impairment is any time all or part of the system is out of service, whether planned for repairs or not. The fire code requires owners to manage impairments carefully:
- Notify the fire department, monitoring company and insurer as your code and policy require.
- Limit the area and time out of service as far as possible.
- Put a fire watch in place where required, and stop hot work and other high-risk activities in the affected area.
- Tag closed valves so nobody forgets them.
- Restore the system as soon as work is done, test it and notify everyone it is back in service.
Closed valves are a leading reason sprinklers fail in real fires. Never leave a valve shut after work.
What the main drain test tells you
The main drain test is one of the simplest and most useful periodic tests. The technician records the static pressure on the riser gauge, opens the main drain fully, records the lower residual pressure while water is flowing, then closes the drain and confirms pressure returns. The numbers on their own mean little. Their value is in comparison with previous tests.
A residual pressure that has dropped noticeably compared with earlier results can point to a partly closed valve, an obstruction in the supply piping, or a change in the municipal supply. It is a prompt to investigate, not a reason to file the report. Ask your contractor to show the trend from year to year in each report.
A typical case
A sprinkler contractor replaces a leaking section of pipe on one floor of an office building. The floor's control valve is closed for the repair, the work is finished, and the crew leaves. Nobody tags the valve or reopens it. The valve's supervisory switch sends a signal to the fire alarm panel, but the property manager assumes it is related to the repair and will clear itself.
Two weeks later, at the next weekly valve check, a member of building staff finds the valve closed and reopens it. Nothing happened in those two weeks, but the floor had no sprinkler protection the whole time. The building then adopted a written impairment procedure: every closed valve is tagged with who closed it and why, the impairment is logged, the fire department and monitoring company are notified as required, and the contractor must reopen the valve, run a main drain test and confirm the supervisory signal has cleared before leaving.
Questions to ask your sprinkler contractor
- Which edition of NFPA 25 and which provincial requirements are you inspecting to?
- How do this year's main drain and fire pump results compare with last year's?
- When are the next internal pipe inspection and sprinkler head sample test due?
- Are any heads painted, corroded, obstructed or of the wrong type?
- Has anything changed in storage or layout that affects the system design?
- What is your procedure for closing and reopening valves during work?
Records
Keep inspection and test reports, impairment records and repair records on file. Fire inspectors and insurers will ask for them. Main drain and fire pump test results are most useful when compared year to year. Sprinkler signals are tied into the fire alarm; see fire alarm system inspections and how fire alarm monitoring works.
How ehZee can help
Through our fire inspections, verification and monitoring service, we review sprinkler inspection reports, records and visible system condition, track deficiencies and impairments to closure and coordinate work with your sprinkler contractor. Testing and repairs must be done by qualified sprinkler contractors.
Common questions
Can we paint over sprinkler heads during a renovation?
No. Painted heads must be replaced, not cleaned. Cover heads during painting and remove the covers immediately afterwards.
Does storage near sprinklers matter?
Yes. Storage too close to heads blocks the spray, and the type and height of storage affects the design the system needs. Changes in storage can mean the existing system no longer protects the space.
What is a supervisory signal from a sprinkler system?
It is a signal to the fire alarm panel that something could stop the sprinkler system working, such as a control valve being closed or low air pressure in a dry system. It needs prompt attention, not just acknowledgement.