TS EN 12845 is the standard that describes not only how to install a sprinkler system, but also how to keep it operating throughout its lifetime On this page, we are translating the standard for readers who are not designers: what the hazard classification determines, what the minimum line is on the water and pump side, which test is performed at what frequency, and what documents should be requested when someone writing this standard into the specification takes over the work.
TS EN 12845 is a European standard that defines the design, installation, and maintenance of automatic sprinkler (spray) systems in a single document. In Turkey, the Regulation on Fire Protection of Buildings specifies which buildings require sprinklers; it leaves how the system shall be calculated and how it shall be kept operational to this standard. Whether sprinklers are mandatory in your building can be checked from the page where we explained Article 96 thresholds; this page describes what comes after the requirement.
Hazard classifications: LH, OH, HH logic
The entire calculation of the standard derives from a single question: how rapidly does the fire grow in this space and how much fuel is available? The answer is divided into three classes. The class determines how many liters of water per minute per square meter will be sprayed (design density) and how many square meters will be wetted simultaneously (operating area):
- LH — Low Hazard: spaces with low fire load and divided into small compartments; such as school and office spaces that meet certain conditions. Design density is on the order of 2.25 mm/min. Because conditions are stringent, it is rarely used in practice.
- OH — Ordinary Hazard (OH1–OH4): hotels, hospitals, shopping centers, parking garages, and most manufacturing spaces. The majority of sprinklered buildings in Turkey fall into this class; density is 5 mm/min, operating area increases according to the subclass.
- HH — High Hazard: divided into two categories. HHP covers hazardous processes (paint booths, lines using solvents), HHS covers high-pile storage. In storage, the class is determined jointly by material type and pile height; density starts at 7.5 mm/min and multiplies according to the storage arrangement.
Practical consequence: the class changes when the space use changes. If a volume calculated as office becomes storage or rack height increases, the system becomes invalid on paper even if the pipe in the ceiling is not touched. In this case, what is needed is not maintenance but recalculation.
Water supply and pump requirements
The standard does not assume water "is present"; it requires duration and reliability. With tank supply, the tank must be capable of providing the design flow rate for a minimum period according to class: 30 minutes for LH, 60 for OH, 90 for HH. City mains can be considered a sole source only if pressure and flow continuity can be proven.
- Pump shall be dedicated solely to fire; when line pressure drops automatic action occurs,but can only be stopped manually — no automatic scenario can shut down the pump during a fire.
- For electrical outage scenarios, an electric + diesel combination or reliable dual supply is established; the diesel motor must be capable of six consecutive start attempts automatically; if unsuccessful, a "failed to start" fault shall appear on the panel.
- A jockey pump that maintains constant pressure is not a substitute for the main pump; frequent engagement of the jockey, or even leakage, is a sign of trouble.
- On the suction side, positive suction where the tank is above the pump level is preferred; a pump drawing air from suction cannot deliver the design flow in the field.
Application details of tests in the pump room fire pump maintenance page.
Test and maintenance schedule
TS EN 12845 maintenance is divided into two: a user program to be carried out by building personnel and comprehensive work to be performed by qualified service. The regulation does not write the period itself; frequency is determined by this schedule and your maintenance contract must match this schedule exactly:
| Period | Test to be performed | Whose responsibility |
|---|---|---|
| Weekly | Reading of water and air pressure gauges, tank water levels, valve open position verification; alarm gong test (water motor alarm operated for at least 30 seconds); pressure reduction test of automatic pump start-up, diesel fuel–oil level; freeze protection in cold periods | Building personnel (with training) |
| Monthly | Diesel starting battery electrolyte level and density, charging system check | Building personnel |
| Quarterly | Review of space use and stacking changes; inspection of heads, pipes and supports; real flow data test-drain line alarm valve and flow switch test; operation of all shut-off valves; electrical supplies | Service |
| Semi-annually | Operation of dry alarm valves; testing of alarm transmission to fire department / monitoring center | Service |
| Annually | Full load flow-pressure test of pump and comparison of results with factory curve; diesel fail-to-start scenario; tank float valves and suction strainers | Service |
| Less frequently | Internal-external inspection of tanks every three years with revision of shut-off and check valves; sampling and testing of heads beyond certain age | Service |
What this schedule translates to in the field — closed valve hunting, flow switch signal tracking, head inspection — sprinkler system maintenance we explained step by step on the page. Intervals should be tightened in dusty, humid, and heavily used facilities.
Summary of differences with NFPA 13
- Classification does not correspond one-to-one. NFPA uses Light/Ordinary/Extra Hazard; EN 12845 treats storage separately as HHS. Mappings like "OH3 = Ordinary Group 2" are approximate and do not substitute for calculation.
- The address of maintenance is different. In the NFPA world, test-maintenance is a separate document (NFPA 25); EN 12845 carries the above schedule within itself.
- Calculation parameters are different. Design densities, operating areas, and layout rules do not overlap; mixing two standards in the same project creates hydraulic inconsistency — a single standard is selected and followed through to the end.
- NFPA regulates seismic hanger in detail; in EN 12845 this scope is limited.
You can find article-by-article comparison in our NFPA 13 and EN 12845 comparison article.
If TS EN 12845 appears in the specification, what will you demand?
Writing the standard name in the specification is easy; unless these documents are requested upon handover, the reference remains on paper:
- Hazard class declaration and hydraulic calculation report — which space in which class, density and operating area. The sentence "complies with EN 12845" does not substitute for calculation.
- Water supply duration calculation — demonstration that tank volume meets the 30/60/90 minutes required by the class.
- Pump characteristic curve and commissioning record — along with flow-pressure points measured in the field.
- Component certificates — heads, alarm valve, and monitoring switches shall be documented according to EN 12259 series.
- User program and maintenance log — adapted version of the schedule for your building; together with training records of personnel who will perform weekly tests.
- As-built project, valve layout diagram, and spare head cabinet.
The standard that keeps the system alive, not just commissioned
The real test of TS EN 12845 is not commissioning day but the fifth year: if weekly pump testing is forgotten, a closed section valve is not reopened after modification, even the most correct calculation becomes non-functional. ASPEK, with its Ankara Yenimahalle-based team, conducts planned regional tours nationwide and remote preliminary diagnosis to test sprinkler systems according to this schedule and produce reports; in facilities not wanting to stay limited to sprinklers, it consolidates all systems from detection to gas suppression in a single maintenance contract, adding CCTV maintenance if desired. Site survey is free within Ankara: You can call or our contact pageA zone monitoring module connects an entire conventional detector line to the addressable loop. Critical areas are renewed with addressable devices while secondary zones continue to operate with their existing wiring. This provides significant cost advantage in capacity upgrade and renovation projects.
Frequently Asked Questions
Is TS EN 12845 mandatory in Turkey?
The obligation derives from the Regulation on Fire Protection of Buildings: the regulation specifies which buildings require sprinklers and regulates their design by reference to this standard. In other words, the answer to "should sprinklers be installed" is in the regulation, and the answer to "how shall they be installed and kept operational" is in TS EN 12845. The maintenance frequency is determined by the standard's own schedule, not by the regulation.
Can we perform weekly tests with our own staff?
Yes — the standard's user program exists precisely for this. Reading pressure gauges, checking reservoir levels, checking valve positions, alarm gong and pump automatic start test can be performed by trained building personnel and recorded in the log. Quarterly and less frequent items (alarm valve flow test, full load pump test, reservoir inspection) are the responsibility of qualified service. We provide this training to your staff in the initial contract.
Our system was designed to NFPA 13; should maintenance be performed to EN 12845?
Testing and maintenance must follow the same family document as the design standard — on the NFPA side, this is a separate document called NFPA 25. The two schedules largely overlap in practice (weekly pump test, quarterly flow tests, annual full load test) but acceptance criteria differ. What matters is not mixing the two standards and stating in the report which standard the test was performed to; our team works in both programs.
How do we find out our building's hazard class?
The correct sources are the system's hydraulic calculation report and as-built drawing; the class, design density and area of application are stated there. If these documents are lost or the building has changed hands, a current condition assessment is performed: the current use of spaces, stack heights and stored materials are evaluated and compared with the current sprinkler head layout. If use has changed, the result is often "maintenance is insufficient, recalculation required" — knowing this is cheaper than learning it during a fire.
Is weekly testing of the fire pump really mandatory?
The standard's user program requires the pump's automatic start to be tested weekly by pressure reduction, and there is good reason: a fire pump is a machine that may run once a year and is most often damaged by standing idle. Start battery, fuel line and pressure switch failures only reveal themselves during testing. A clean-looking pump room at a facility without weekly tests proves nothing.
How do we know if our existing system complies with TS EN 12845?
Assessment is performed at three levels: documentation (hydraulic calculation, duration calculation, commissioning record present), field (sprinkler head layout matches current use, valves are accessible, water supply meets duration requirement) and operations (is the weekly user program actually being carried out, are records being maintained). We provide this assessment as a single-visit status report; inspection is free within Ankara, elsewhere it is added to our planned regional tours.