In TS EN 12845+A2:2026 marking is collected in Clause 18, headed "Signs, notices, and information" (TS p.118-120 / EN p.115-117). Clause 18.1 covers the block plan and 18.2 the plates and notices. This article gives all the subheadings of the clause, the letter heights and colour rules that appear in the text with their sources, and also shows that the frequently confused spare sprinkler cabinet provision is not in Clause 18 but in Clause 20.1.4.
Clause 18.1: Block plan
The standard (TS p.118 / EN p.115): a block plan of the premises shall be placed near a main entrance or in another position where it can readily be seen by the fire brigade or by other persons responding to an alarm. The plan shall show:
- a) the installation number and the location of the relevant control valve set and water motor alarm;
- b) each separate hazard classification area, the relevant hazard class and, where appropriate, the maximum storage height;
- c) the area covered by each installation, by colour shading or hatching, and, if required by the fire brigade, an indication of the routes through the premises to those areas;
- d) the location of any subsidiary stop valves.
The block plan is not a sign at the control valve; its place is the main entrance or a point visible to the fire brigade. The standard gives no provision on the size, material, lettering height or fire resistance of the block plan.
The hazard class naming in item b) of the block plan is based on Clause 6.2 (TS p.34-35 / EN p.31-32): LH; OH1 to OH4; HHP1 to HHP4; HHS1 to HHS4.
Clause 18.2: Signs and notices
18.2.1 Location plate
A location plate of weather resistant material and lettering shall be fixed to the outside of the external wall as close as possible to the entrance nearest to the control valve sets (TS p.118 / EN p.115). The plate shall bear the following wording:
| Wording | Minimum letter height |
|---|---|
| SPRINKLER STOP VALVE | 35 mm |
| INSIDE | 25 mm |
The lettering shall be white on a red background.
18.2.2 Signs for stop valves
A sign bearing the following words shall be fitted close to the main and any subsidiary stop valves (TS p.118 / EN p.115):
'SPRINKLER CONTROL VALVE'
The sign shall be rectangular, with white letters at least 20 mm high on a red background.
Where the stop valve is in a room with a door, the sign shall be fixed to the outside of the door and a second sign bearing the words 'Keep door locked' shall be placed on the inside of the door. The second sign shall be circular, with white letters at least 5 mm high on a blue background.
This is the only place in the standard where a letter height of 5 mm appears.
18.2.3 Control valve set
18.2.3.1 General (TS p.118 / EN p.115): where the sprinkler system consists of more than one installation, each control valve set shall be clearly marked with a number identifying the installation it controls.
18.2.3.2 Control valve notice (TS p.119 / EN p.116): a durable notice shall be fixed to the rise pipe adjacent to each control valve set. The notice shall contain the following information:
- the installation number;
- the hazard classification or classifications of the installation;
- for each hazard class area within the installation: 1. the design requirements (area of operation and discharge density); 2. whichever is applicable, the pressure/flow requirement at the flow testing installations or the pressure/flow requirement at the pump outlet pressure gauge, for the most and least favourable areas of operation.
The source of the design requirements to be written on this notice is Table 3 (Clause 7.1, TS p.39 / EN p.36). Example rows: for OH3, a density of 5.0 mm/min and an area of operation of 216 m² in a wet/pre-action system and 270 m² in a dry/alternate system; for HHP1, 7.5 mm/min and 260 m² (dry/alternate 325 m²). For HHS the area of operation comes from Table 4 (TS p.41 / EN p.38): 260 m² for design densities in the range 7.5 to 17.5 mm/min and 300 m² in the range 20.0 to 30.0 mm/min.
18.2.4 Water supply connections to other services
A label shall be fixed to stop valves controlling water supplies to other services from the sprinkler system supply pipes or mains; the label shall be marked appropriately, for example 'Firefighting hose reels' or 'Domestic water supply', in raised or printed letters (TS p.119 / EN p.116).
18.2.5 Suction and booster pumps
18.2.5.1 General (TS p.119 / EN p.116): a nameplate shall be fixed to each suction or booster pump bearing the following information:
- a) the outlet pressure in bar at the inlet condition and flow rate specified in Table 16, together with the corresponding rated speed and flow rate in litres per minute;
- b) the maximum power absorbed at any flow rate at the relevant speed.
18.2.5.2 Fully calculated installations (TS p.119 / EN p.116): installer data in accordance with EN 17451 shall be displayed at the pump: the pump supplier's data sheets; a schedule listing the technical data specified in 4.4.4.4; a copy of the installer's pump characteristic sheet.
18.2.6 Electrical switches and control panels
18.2.6.1 Alarms transmitted to the fire brigade (TS p.119 / EN p.116): where water flow into an installation initiates an automatic alarm to the fire brigade, a notice stating this shall be fixed adjacent to the alarm test valve(s).
18.2.6.2 Diesel pump set (TS p.119-120 / EN p.116-117): the alarms specified in Clauses 10.8.5.1 and 10.9.2 shall be marked appropriately both at the pump set control unit and in the location with responsible personnel:
- a) diesel fire pump starter switched off;
- b) diesel fire pump failure to start;
- c) pump running;
- d) diesel controller fault.
The manually operated shut down mechanism shall be labelled: 'SPRINKLER PUMP SHUT-OFF'.
18.2.6.3 Electric motor driven fire pump (TS p.120 / EN p.117): each switch in the dedicated power supply to the electric sprinkler pump set shall be labelled:
'SPRINKLER PUMP MOTOR SUPPLY - NOT TO BE SWITCHED OFF IN THE EVENT OF FIRE'
The letter height and colour of the same label are given in Clause 10.8.3.2 (TS p.68 / EN p.65): the letters on the notice shall be at least 10 mm high and white on a red background; the switch shall be locked to protect it against interference.
18.2.7 Testing and operating devices
All valves and instruments used for testing and operating the system shall be labelled appropriately. The corresponding identification shall be included in the documentation (TS p.120 / EN p.117).
This clause is directly linked to the commissioning documentation: Clause 19.2 (TS p.121 / EN p.118) requires the 'as-built' design documents the installer provides to the user to include the identification of all valves and instruments used for testing and operating.
The marking on the water motor alarm
There is one more marking provision outside Clause 18: Clause 16.1.1 (TS p.113 / EN p.110) requires each water motor alarm gong to be clearly marked with the number of the installation it controls. A single alarm motor and gong may be shared by a group of wet alarm valves; in that case an indicator showing that it has operated is fitted to each alarm valve.
The spare sprinkler cabinet: not in Clause 18 but in Clause 20.1.4
The spare sprinkler provision is neither in Clause 14 nor in Clause 18. Clause 14 ends at 14.9. The correct address is Clause 20.1.4 Replacement sprinklers (TS p.121-122 / EN p.118-119).
The standard requires the following:
- A stock of spare sprinklers shall be held on the premises for use in replacing operated or damaged sprinklers.
- The spare sprinklers, together with the sprinkler spanners supplied by the supplier, shall be kept in a cabinet or cabinets in a conspicuous and readily accessible position where the ambient temperature does not exceed 27 °C.
- The number of spare sprinklers per system shall not be less than:
| Installation class | Minimum number of spare sprinklers |
|---|---|
| LH installations | 6 |
| OH installations | 24 |
| HHP and HHS installations | 36 |
- The stock shall be replenished immediately after spares have been used.
- Where the installations include high temperature sprinklers, sidewall sprinklers or other sprinkler pattern variations, or where there are multiple controls, a sufficient number of spares of these shall also be held.
The numbers depend on the hazard class; there is no table in the standard graded by the total number of sprinklers. Nor does the standard require the cabinet to be locked, to be located next to the control valve set, or to have a defined clear space in front of it.
Counting the spares also appears in the maintenance schedule: Clause 20.3.2.9 (TS p.124 / EN p.121) requires the number and condition of the replacement parts held in stock to be checked in the quarterly routine carried out at intervals of not more than 13 weeks.
What Clause 18 does not cover
The following do not appear in the text of TS EN 12845+A2:2026; if they are to enter a specification, their source shall be shown as something other than EN 12845:
- A paper or board size requirement (A3 and the like) for the block plan or the signs
- Fire resistance duration, reflectivity or a specific size (for example 600 × 400 mm) for the signs
- Pipe painting colours, flow direction arrows on pipes or the word 'SPRINKLER' at set intervals
- A requirement for the signs to be legible under emergency lighting
- A defined clear space in front of a sign or a cabinet
- A separate checklist for yearly cleaning and legibility checks of the signs
Field note
The notice required by Clause 18.2.3.2 is the only document that keeps a summary of the design at the head of the valve: installation number, class, density, area of operation and pressure/flow. Keeping the values of this notice identical to the as-built, together with the "corresponding identification in the documentation" requirement of Clause 18.2.7, fixes the reference against which the values measured in the quarterly and yearly tests will be compared. (This paragraph is engineering commentary.)
Frequently Asked Questions
Where is the block plan displayed and what does it show?
TS EN 12845+A2:2026 Clause 18.1 (TS p.118 / EN p.115): a block plan of the premises shall be placed near a main entrance or in another position where it can readily be seen by the fire brigade or by other persons responding to an alarm. The plan shall show: a) the installation number and the location of the relevant control valve set and water motor alarm; b) each separate hazard classification area, the relevant hazard class and, where appropriate, the maximum storage height; c) the area covered by each installation by colour shading or hatching and, if required by the fire brigade, the routes to those areas; d) the location of any subsidiary stop valves.
What is the letter height of the 'SPRINKLER STOP VALVE' sign?
Clause 18.2.1 Location plate (TS p.118 / EN p.115): a location plate of weather resistant material and lettering shall be fixed to the outside of the external wall as close as possible to the entrance nearest to the control valve sets. The plate shall bear the words 'SPRINKLER STOP VALVE' in letters at least 35 mm high and the word 'INSIDE' in letters at least 25 mm high. The lettering shall be white on a red background.
What does the sign next to the control valve set say?
There are two separate signs. Clause 18.2.2 (TS p.118 / EN p.115): a sign bearing the words 'SPRINKLER CONTROL VALVE' shall be fitted close to the main and any subsidiary stop valves; the sign shall be rectangular, with white letters at least 20 mm high on a red background. Clause 18.2.3.2 (TS p.119 / EN p.116) requires a durable notice to be fixed to the rise pipe adjacent to each control valve set: the installation number, the hazard classification of the installation, and for each hazard class area the design requirements (area of operation and discharge density) together with the pressure/flow requirement for the most and least favourable areas of operation.
How many spare sprinklers shall be held?
Clause 20.1.4 (TS p.121-122 / EN p.118-119): the number of spare sprinklers per system shall not be less than 6 for LH installations, 24 for OH installations and 36 for HHP and HHS installations. The number depends on the hazard class, not on the total number of sprinklers. Where the installation includes high temperature sprinklers, sidewall sprinklers or other pattern variations, or multiple controls, a sufficient number of spares of these shall also be held.
Where is the spare sprinkler cabinet located?
Clause 20.1.4 (TS p.121 / EN p.118): the spare sprinklers, together with the sprinkler spanners supplied by the supplier, shall be kept in a cabinet or cabinets in a conspicuous and readily accessible position where the ambient temperature does not exceed 27 °C. The standard does not require the cabinet to be locked or to be located next to the control valve set.
References
- TS EN 12845+A2:2026 Clause 18.1 Block plan, 18.2.1 Location plate, 18.2.2 Signs for stop valves, 18.2.3.1 (TS p.118 / EN p.115)
- TS EN 12845+A2:2026 Clause 18.2.3.2 Control valve notice, 18.2.4, 18.2.5.1, 18.2.5.2, 18.2.6.1, 18.2.6.2 (TS p.119 / EN p.116)
- TS EN 12845+A2:2026 Clause 18.2.6.2 b)-d), 18.2.6.3, 18.2.7 (TS p.120 / EN p.117)
- TS EN 12845+A2:2026 Clause 10.8.3.2 Label letter height and colour (TS p.68 / EN p.65)
- TS EN 12845+A2:2026 Clause 16.1.1 Water motor alarm marking (TS p.113 / EN p.110)
- TS EN 12845+A2:2026 Clause 6.2 Hazard classes (TS p.34-35 / EN p.31-32)
- TS EN 12845+A2:2026 Clause 7.1, Table 3 (TS p.39 / EN p.36)
- TS EN 12845+A2:2026 Table 4 (TS p.41 / EN p.38)
- TS EN 12845+A2:2026 Clause 19.2 Completion certificate and documents (TS p.121 / EN p.118)
- TS EN 12845+A2:2026 Clause 20.1.4 Replacement sprinklers (TS p.121-122 / EN p.118-119)
- TS EN 12845+A2:2026 Clause 20.3.2.9 Replacement parts (TS p.124 / EN p.121)
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Download MEP Calc on the App StoreTS EN 12845+A2:2026 (EN 12845:2015+A2:2026) Fixed firefighting systems — Automatic sprinkler systems — Design, installation and maintenance; TS EN 12845-2:2025 (EN 12845-2:2024) ESFR and CMSA sprinkler systems. Every figure in this article is taken from the published standard text; clause, table and page references are listed under References. General information only, not a substitute for the standard or for a design review.