Automatic sprinklers have an excellent track record, as long as water reaches them. Almost every sprinkler failure traces back to something routine servicing is meant to catch: a closed valve, a failed alarm, a change in what’s stored under the heads, or components that have simply aged past their reliable life.
AS 1851-2012 covers sprinklers in Section 2, and its schedule runs further into the future than any other system in the standard: from monthly alarm tests to sample testing of sprinkler heads at 25 years, and a 30-yearly item. This guide walks through every interval, with the long-interval work (the part most often missed and most often underquoted) covered in detail.
Design and maintenance: two standards
Sprinkler systems are designed, installed and commissioned to AS 2118.1 (the current edition is AS 2118.1:2017, with amendments), which also sets how occupancies are classified. They’re maintained to AS 1851-2012 Section 2. ACT Fire & Rescue’s guideline maps them exactly that way: installed to AS 2118.1 and maintained to AS 1851-2012, Section 2.
Section 2 has separate schedules for each system type (wet pipe, dry pipe, deluge and water spray, and pre-action systems) because each has its own valves and alarm arrangements. Most buildings have wet pipe systems, and that’s the focus here.
Frequencies and tolerances
Building Commission NSW’s good practice guide summarises the sprinkler intervals and the tolerance allowed either side of each scheduled date:
| Interval | Tolerance |
|---|---|
| Monthly | ± 5 working days |
| Six-monthly | ± 1 month |
| Yearly | ± 2 months |
| Five-yearly | ± 3 months |
| 10-yearly | ± 6 months |
| 25-yearly | ± 6 months |
| 30-yearly | ± 6 months |
Sprinklers are the only system in the matrix with a 30-yearly interval. Anything done outside its tolerance is an out of tolerance activity: recorded as a non-conformance in the logbook and carried out as soon as practical.
Before any sprinkler test: managing the impairment
Many sprinkler service activities take part of the system out of service, or send an alarm to the fire brigade if nobody has planned for it. Before any test that impairs the system or operates an alarm:
- Tell the building manager and, where the system is monitored, the monitoring provider, so a test signal doesn’t turn into a brigade call-out.
- Know exactly which valves you’ll operate and which parts of the building they protect.
- Keep isolations as short as possible, and never leave site with a valve closed or the system impaired without the responsible entity knowing.
- For longer impairments (the five-yearly work or a sample test), agree interim measures with the owner in advance.
- Restore everything, confirm pressures are back to normal, and confirm alarms are clear before you leave.
Monthly
The monthly visit proves the system is alive: water at pressure, valves open, and alarms that reach the people who need to know.
- Record the system pressure from each gauge before the alarm function test, and again after it.
- Test the alarm: FPA Australia’s baseline data guide quotes the monthly item as verifying the correct operation of each alarm signal and, where the system is monitored, making sure the alarm has activated the alarm signalling equipment.
- Check the installation’s valves are in their correct position and secured. A closed main stop valve is the single most serious sprinkler finding there is.
For dry pipe, deluge and pre-action systems, the monthly alarm test is carried out by simulation (for example, operating local and fire brigade alarms through the bypass valve) rather than by operating the main valve.
Six-monthly
- Record each gauge reading before the main drain test, then carry it out. The drop in pressure and its recovery tell you about the supply and the valves.
- Functionally test the town main supply.
- For dry pipe, deluge and pre-action systems, the six-monthly schedule includes tests of the alarm valve and its auxiliaries, and of the local and fire brigade alarms, including accelerators or exhausters on dry pipe systems.
Yearly
The yearly service is where performance gets measured against the design. FPA Australia’s baseline data guide identifies the yearly wet pipe items that rely on baseline data:
| Item | What it verifies | Benchmark |
|---|---|---|
| Pressure-reducing valve test (high rise) | Pressures on the low-pressure side are within the range stated at the valve station | Pressure gauge label at the PRV station |
| Water supply proving test | The system’s flow and pressure requirements are satisfied | Block plan or approved design documentation |
| Sprinkler system interface test (fire trips) | Interfaces with other systems function as required | Cause and effect chart |
| Tank quick-fill test, where fitted | The flow matches the required quick-fill rate | Approved design documentation |
| Occupancy survey | The sprinkler design is still right for the occupancy hazard classification and category of storage | Approved design documentation |
| Storage survey | The design is still right for storage heights and encapsulation | Approved design drawings |
The water supply proving test is only meaningful against a benchmark. Building Commission NSW identifies sprinkler flow and pressure performance data as baseline data AS 1851 relies on, and where it’s missing, the test is still done and the missing data reported as a non-conformance.
Five-yearly
Every five years, wet pipe systems get what amounts to an overhaul of their valves and alarms. FPA Australia summarises the five-yearly activities (Table 2.4.2.4, items 4.1 to 4.17) as:
- Replace alarm valve seatings and face plate gaskets.
- Replace washers and gland packing as required, and make sure component parts operate as required.
- Check jacking pumps (hand and electric) operate correctly, and maintain them to the manufacturer’s instructions.
- Repack stop valves and replace check valve seatings.
- Service the water-operated local alarm.
- Verify every pressure gauge reads within ± 30 kPa of a master gauge.
- Overhaul all speciality valves.
- Fully drain tail-end anti-freeze systems and refill with new solution.
- Service air compressors to the manufacturer’s instructions.
- For foam-water systems, confirm foam quality and proportioning ratio, and replenish the foam.
This is a substantial, planned shutdown: valves out of service, system drained in part, impairment management in place. It deserves its own quote and its own date, agreed well in advance.
10 and 25 years: sprinkler sample testing
Sprinkler heads don’t last forever. Corrosion, loading and age can change the temperature at which a head operates, or stop it operating at all. AS 1851-2012 deals with that by sampling (Table 2.4.2.4, items 4.18 and 4.19):
- Dry pendent sprinklers: a representative sample removed and tested every 10 years. FPA Australia notes the sample size depends on site conditions and the number of dry pendent heads installed.
- All other sprinklers: a representative sample of not less than 14 sprinklers, removed and tested at 25 years, then every 10 years after that.
- The samples are tested by a registered testing authority for release temperature, function, and leak resistance at the maximum system design pressure.
FPA Australia’s guidance adds two practical points. The sample should represent the building’s different environments (offices, concealed spaces, plant rooms, car parks, warehousing) because heads in a car park age differently from heads above a ceiling. And the 25-year clock runs from the system installation date shown on the block plan.
Planning a 25-year sample test
- Find the installation date: on the block plan, or from commissioning records. Put it on the asset register years ahead.
- Plan the sample: at least 14 heads, spread across the environments in the building.
- Source replacement heads that match those being removed (the same type, response and temperature rating) so the system goes back into service as designed.
- Arrange the impairment: drain-down, isolation, notifications and any interim measures the owner decides on.
- Remove, label and send the samples to a registered testing authority, with their locations recorded.
- Record the results against the system, and report them to the owner.
If samples fail, the results, together with advice from the testing authority and a sprinkler designer, should guide what comes next, which may mean replacing more heads of that type. Either way, quote the sample test itself as a separate, scheduled project, and flag the possibility of follow-on work early.
30 years: the MJC test
The 30-yearly item isn’t a sprinkler system overhaul, whatever you may read. FPA Australia summarises it as testing a single multiple jet control (MJC) installed for alarm purposes at 30 years, then every 10 years, and notes that replacing the MJC can be considered instead of testing it. If a system doesn’t have one, the item doesn’t apply.
What isn’t in the sprinkler schedule
- A periodic hydrostatic test of sprinkler pipework. AS 1851’s hydrostatic test is a hydrant system activity where a fire brigade booster is installed; Building Commission NSW’s hydrostatic test appendix is written for hydrant systems.
- American rules. You’ll find NFPA 25 requirements online, for example different test ages for fast-response sprinklers. They aren’t AS 1851 requirements.
- A blanket “replace every head at 25 years” rule. The 25-year activity is sample testing; what happens next depends on the results.
Budgeting for the long-interval work
The five-yearly overhaul and the 25-year sample test are the two sprinkler activities most likely to catch an owner by surprise, and most likely to be underquoted by a contractor who didn’t see them coming. Put them in the forward plan early:
| Activity | When | What to plan for |
|---|---|---|
| Five-yearly valve and alarm overhaul | Every five years | Parts (seatings, gaskets, packing), valve shutdowns, gauge checks against a master gauge, and the impairment |
| Dry pendent sample test | Every 10 years, where fitted | Sample removal, replacement heads, registered testing authority fees |
| Sprinkler sample test | At 25 years from installation, then every 10 years | At least 14 heads across the building’s environments, matching replacements, laboratory testing, drain-down and impairment |
| MJC test or replacement | At 30 years, then every 10 years, where fitted | Test or replacement of a single MJC used for alarm purposes |
Owners budget much better for work they can see coming. A forward plan listing each item, its year and an indicative cost turns a 25-year surprise into a line in the owners corporation’s budget.
Block plans
The block plan at the valve set is the sprinkler system’s identity card. Building Commission NSW notes block plans have been required on sprinkler systems in NSW since the 1970s. They carry the hydraulic information the yearly water supply proving test is measured against, and the installation date the 25-year test is counted from.
Where a block plan is missing or wrong, the NSW guide’s method for re-establishing it applies: gather site data (including alarm valve size, number, location and year, water supply proving test results with each supply tested independently, the reduced level of the highest sprinkler head, and the sprinkler hazard classification) and have an accredited or registered hydraulic designer prepare and verify a new one.
Common sprinkler defects
| Finding | Typical classification | Why |
|---|---|---|
| Main stop valve or installation valve closed | Critical | The system has no water, so it can’t control a fire |
| Water supply impaired so the system can’t be fed | Critical | The system can’t deliver its design performance |
| Alarm not reaching the monitoring provider | Usually critical | The brigade won’t be called automatically |
| Storage too close to sprinkler heads | Depends on extent | AS 2118.1 requires clear space below sprinkler deflectors |
| Painted, damaged, corroded or loaded heads | Depends on extent | Heads may not operate as designed |
| Water motor or local alarm not working | Usually non-critical | The system still operates; a warning function is lost |
| Missing spare sprinklers, block plan or legible labels | Non-conformance | Information or features needed for ongoing servicing |
These are typical, not automatic. Classification depends on the building and the system. A critical defect is reported before leaving site, or as soon as possible, and confirmed in writing within 24 hours; the others within one week.
Who can do the work
- NSW: Building Commission NSW lists plumbing work (for example, hydrant and sprinkler systems) as specialist work that must be done under an appropriate licence. A water plumber (fire sprinkler system) licence covers installation beyond the sprinkler valve assembly only.
- Victoria: the Building and Plumbing Commission treats routine servicing, maintenance, testing or commissioning of any part of a water service used for fire fighting as fire protection plumbing work.
- Queensland: QBCC’s water-based fire system install-and-maintain licence covers sprinkler systems.
- ACT: ACT Fire & Rescue recognises nationally recognised units of competency as an appropriate way to demonstrate competence.
Records
- Gauge readings before and after each alarm and drain test, and every yearly flow and pressure result against its benchmark.
- A logbook recording each activity as a pass or fail, the AS 1851 section and interval, defects and corrective action, with a hard copy left on site.
- The system installation date, and the dates and results of the 10- and 25-year sample tests.
- Occupancy and storage survey outcomes, including any change reported to the owner.
- Records kept for at least seven years in NSW.
Frequently asked questions
How often are sprinklers serviced under AS 1851?
Monthly, six-monthly, yearly and five-yearly, with 10-, 25- and 30-yearly items. The monthly tolerance is five working days either side of the scheduled date.
Do all sprinkler heads have to be replaced at 25 years?
No. At 25 years, a representative sample of at least 14 heads is removed and tested by a registered testing authority, and sampling repeats every 10 years. The results decide what happens next.
When does the 25-year clock start?
From the system installation date. FPA Australia points to the date shown on the block plan.
What’s tested at 30 years?
A single multiple jet control (MJC) installed for alarm purposes, then every 10 years, or the MJC can be replaced instead.
Is there a five-yearly hydrostatic test for sprinklers?
Not in AS 1851’s sprinkler schedule. The periodic hydrostatic test belongs to hydrant systems with a booster connection.
Who tests the removed sprinkler heads?
A registered testing authority, which tests the samples for release temperature, function and leak resistance at the maximum system design pressure.
What if the building changes use?
Tell the owner in writing. The yearly occupancy and storage surveys exist to check the sprinkler design still suits the hazard. A change of use or storage may mean the design needs reviewing by a sprinkler designer.
Sources and further reading
- Good practice guide for the inspection, testing, maintenance and repair of fire protection systems in NSW buildings, Building Commission NSW (January 2026)
- AS 1851-2012 post-annual servicing requirements, Fire Protection Association Australia
- Good Practice Guide 05: Baseline data, Fire Protection Association Australia
- FSG-05 Maintenance of fire protection systems and equipment, ACT Fire & Rescue (August 2023)
- Automatic fire sprinkler system, Building Commission NSW plumbing guidance
- Fire protection: water-based fire system licence, Queensland Building and Construction Commission