What does this tool do?
TS EN 12845-2 (EN 12845-2:2024) gives ESFR and CMSA sprinkler designs for storage as tables. For the goods class, storage type, storage height and ceiling height you choose, the tool lists the rows that actually exist in the tables: k-factor, orientation, number of sprinklers in the design, minimum operating pressure, water supply duration from Table 6 and the conditions of the row (aisle width, in-rack sprinklers, water delivery time). Where no table row matches, it says “not covered”; it never interpolates or extrapolates (Clause 6.1).
Which tables?
| System | Table | Scope |
|---|---|---|
| ESFR | 7 | HHS1–HHS5, ceiling only, 12 sprinklers |
| ESFR | 8 / 9 | Rubber tyres / roll paper on end |
| ESFR | 10 / 11 | 6.6.1.2 designs with special requirements (up to 12.2 m and 16.8 m ceilings) |
| CMSA | 15 / 16 | STC1: HHS1/HHS2 and HHS3–HHS5 |
| CMSA | 17–20 | STC4.1–STC4.3 open-frame racks |
| CMSA | 21 | Special dry-pipe designs (upright, 141 °C, tree layout) |
| CMSA | 22 / 23–25 | Rubber tyres / roll paper |
ESFR designs combined with in-rack sprinklers (Clause 6.6.2, Tables 12–14) are not included; they depend on the rack geometry.
Selection rules (Clause 6.1)
- No interpolation or extrapolation. A design for a given ceiling height may be used under a lower ceiling provided no other parameter changes, so the tool shows the matching row with the lowest ceiling for each design.
- Unless otherwise specified, HHS3 protection is used for HHS1 and HHS2. A design for a higher category also protects a lower one.
- If more than one single pallet load of a higher category is stored in any 300 m², the design follows that category.
- Goods not covered by the tables, such as flammable liquids and aerosols, are not protected to this standard; EN 12845 applies.
- All flues at least 150 mm, loading aisles at least 1.2 m; in STC3 and STC4.3 at most 6 m between loading aisles.
- At least 1 m clear space between the deflector and the top of storage (5.1.3.7).
Wet or dry?
ESFR sprinklers are used in wet installations only (Clause 4); there is no dry ESFR option and an installation with dry pendent ESFR counts as wet (6.5). CMSA may be used in wet and dry installations. For dry CMSA the water delivery time is 40 s with 4 sprinklers operating unless the table says otherwise (6.7.1).
Duration and design area (Table 6)
| Sprinklers | Duration (min) | Shape |
|---|---|---|
| 9 / 10 / 12 | 60 | 3 × 3 · 3 × 2 + 4 × 1 · 4 × 3 |
| 15 / 16 | 90 | 5 × 3 · 5 × 3 + 1 × 1 |
| 20 / 24 / 25 / 30 | 120 | 5 × 4 · 6 × 4 · 6 × 4 + 1 × 1 · 7 × 4 + 2 × 1 |
With CMSA, roll paper needs 120 min and rubber tyres 180 min regardless of the number of sprinklers (Table 6 NOTES 2 and 3). Table 21 has its own duration column. No favourable design area is required and no diameter reduction to limit the favourable-area demand is allowed.
Spacing and position
- ESFR (5.1.3.2): at least 2.4 m between sprinklers; at most 3.7 m (ceiling ≤ 9.1 m) or 3.1 m (ceiling > 9.1 m); 6.0–9.3 m² per sprinkler.
- CMSA (5.1.3.3): 2.4–3.7 m (3.1 m under combustible obstructed construction); at least 7.5 m² and at most 9.3 m² per sprinkler; 12 m² for STC1 under an unobstructed non-combustible, obstructed non-combustible or unobstructed combustible ceiling.
- The distance to walls is no more than 50 % of the maximum spacing. To avoid an obstruction the spacing may exceptionally be extended by 0.3 m, with up to 10.2 m² per sprinkler (5.1.3.4).
- The maximum distance of the thermal element below the ceiling is in Table 2 (e.g. ESFR K360 425 mm, K400 325 mm); the deflector is at least 100 mm below the ceiling (5.1.3.5.2).
The tables apply only if the sprinkler has been successfully tested for that ceiling height, storage height, goods and storage type (5.1.1). STC classes are defined in prEN 12845-1.
Frequently Asked Questions
What if my exact ceiling height is not in the table?
No interpolation. Under EN 12845-2 Clause 6.1, a design for a given ceiling height may be applied to a lower ceiling height provided no other parameter changes. A 9.8 m ceiling therefore uses the 10.7 m row; the tool shows it with the note “usable under a lower ceiling”.
Can ESFR be used in a dry installation?
No. ESFR sprinklers are used in wet installations only (Clause 4); there is no dry ESFR option and an installation with dry pendent ESFR counts as wet (6.5). For dry installations there are CMSA tables (e.g. Tables 15, 17, 18 and 21).
Which rows apply to HHS1 or HHS2 goods?
Unless otherwise specified, HHS3 protection is used for HHS1 and HHS2 (6.1). CMSA Tables 15, 17, 18 and 21 give separate rows for HHS1/HHS2; the tool lists them together with the HHS3 rows.
How is the water supply duration found?
Table 6 gives the duration from the number of sprinklers in the design: 9, 10 and 12 sprinklers 60 min; 15 and 16 sprinklers 90 min; 20, 24, 25 and 30 sprinklers 120 min. With CMSA, roll paper needs 120 min and rubber tyres 180 min; Table 21 has its own duration column.
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