Fire standards, explained and calculated.

538 technical articles on NFPA, BS EN 12845, FM Global and Turkey’s BYKHY; 30 fire calculations that run in your browser. An archive that grows with questions from the field.

ESFR K-factor Water tank NPSH Compartment

technical articles: 538
fire calculations in the browser: 30
FAQ entries: 1700+
NFPA documents with edition years: 422

Standard → calculation → result

From clause to number, in one line.

A clause in the libraries becomes an input in the calculations. Example: from FM Global DS 8-9 to the flow of a single ESFR sprinkler.

Library

NFPA Knowledge Base212 BS EN 12845105 FM Global54 BYKHY35

Fire calculation

ESFR suitability check K-factor flow and pressure Beam rule: obstruction distance Fire water tank volume Are sprinklers required?

Result

Example · ESFR

ESFR K360 (K25.2) · 1.4 bar

Q = K·√P

≈426L/min

Q = 360 × √1.4 ≈ 426 L/min per sprinkler

70 °C
FM DS 8-9 Table 7
9 m ceiling

Open the ESFR calculation

Knowledge Base

Four libraries,
one archive.

Each standard has its own library: clauses, tables, calculation methods and what they mean on site. Archive

212articles

NFPA Knowledge Base

35+ standards in two languages (TR/EN). Sprinklers, standpipes, fire pumps, ITM, fire alarm, smoke control and clean agent suppression.

NFPA 13
14
20
25
72
92
2001

NFPA 13 beam rule 3D explainer: pendent sprinkler A = 3 ft (900 mm) from a concrete beam with the deflector 7.1 in (180 mm) above the beam bottom; Table 10.2.8.2 allows B up to 9½ in (240 mm) for this row.

105articles

EN 12845 Knowledge Base

3 design modes, 2 standards: EN 12845:2015+A2:2026 and EN 12845-2:2024. Hydraulic calculation, pump room, water supply, Annex N/O/P.

CMDA
CMSA
ESFR
K factor

TS EN 12845+A2 Table 19 sprinkler layout plan: OH standard layout at S 4.0 m and D 3.0 m spacing, 12.0 m² per sprinkler.

54articles

FM Global

Property Loss Prevention Data Sheets in 4 DS families: sprinkler installation, water supply, industrial occupancies and storage. Pumps, tanks, ESFR, ASRS, Li-ion.

DS 2-x
3-x
7-x
8-x

In-rack sprinkler 3D explainer: double-row rack, H = 30 ft (9.1 m), 6 in (150 mm) longitudinal and transverse flues, in-rack sprinklers on two levels.

35articles

Turkish Regulation (BYKHY)

The Turkish Regulation on Fire Protection of Buildings: compartments, existing buildings, sprinkler requirements, fire water and hydrants.

15building types

What you need
most often.

Sprinkler flow, glass bulb colours, placement distances and area × density demand (NFPA 13 and EN 12845): the everyday questions from design and site, with the standard's table, in one place.

Sprinkler flow · Q = K·√P

Pick a K-factor, slide the pressure; the flow updates instantly. The full calculator and per-K flow tables are one click away.

K-factorL/min/bar½

Or type any value.

Pressure P0.5–12 bar

bar

Q = 360 × √1.40

426L/min

≈ 112.5 gpm1.40 bar ≈ 20.3 psi

Worked example: FM DS 8-9 Table 7 · Class 1–3 commodities, open-frame racks, min. 4 ft (1.2 m) aisles, wet system, max. ceiling height 30 ft (9.0 m) · K360 (K25.2) quick-response pendent sprinkler, 160 °F (70 °C): 9 sprinklers @ 20 psi (1.4 bar) → Q = 360 × √1.4 ≈ 426 L/min per sprinkler.

Full calculator K360flow table

Flow–pressure curve · K360 (K25.2)

Curves are drawn from Q = K·√P alone; the K-factors match the site's flow tables. For design and minimum pressures, see the relevant standard.

Glass bulb colours and temperatures

Temperature rating selector

NFPA 13-2025 Table 7.2.4.1(a) · EN 12845 Table 37b

Orange57 °C135 °FOrdinaryCeiling ≤ 38 °CEN 12845 57 °C
Red68 °C155 °FOrdinaryCeiling ≤ 49 °CEN 12845 68 °C
Yellow79 °C175 °FIntermediateCeiling ≤ 66 °CEN 12845 79 °C
Green93 °C200 °FIntermediateCeiling ≤ 66 °CEN 12845 93 · 100 °C
Blue121–149 °C250–300 °FHighCeiling ≤ 107 °CEN 12845 121 · 141 °C
Purple163–191 °C325–375 °FExtra highCeiling ≤ 149 °CEN 12845 (mauve) 163 · 182 °C
Black204–343 °C400–650 °FVery extra high · Ultra highCeiling ≤ 191 / 246 / 329 °CEN 12845 204 · 227 · 260 · 286 · 343 °C

NFPA 13 (9.4.2.2): where the maximum ceiling temperature exceeds 100 °F (38 °C), choose the rating by the maximum ceiling temperature in Table 7.2.4.1(a) (“Ceiling ≤” on the cards). EN 12845 (14.4): choose a rating close to, but at least 30 °C above, the highest expected ambient temperature. On fusible-link sprinklers the colour is on the frame arms under EN 12845 (Table 37b), and on the frame arms, deflector or coating under NFPA 13 (7.2.4.1); the selector shows them separately.

Sprinkler placement rules

Distances below the ceiling, from walls and between sprinklers under NFPA, EN 12845 and FM Global, side by side for sidewall, CMDA, CMSA and ESFR.

NFPA 13
EN 12845
FM Global
Sidewall
CMDA
CMSA
ESFR

Area × Density Calculator

Pick the standard and hazard class: density × area, plus the hose allowance for NFPA 13 or hose reels and hydrants for EN 12845. Total flow, pressure and water volume on one screen.

NFPA 13 · LH–EH2
EN 12845 · LH–HHP3
Hose · reels · hydrants

EN · 5.0 mm/min × 144 m²=720 L/min+reels + hydrantsNFPA · 0.20 gpm/ft² × 1,500 ft²=300 gpm+hose 250 gpm Wet system, preliminary sizing; OH2 example (class definitions differ) · d × A: EN 12845 Table 3, NFPA 13 Table 19.2.3.1.1 (SI column) · BYKHY Annex 8/C · NFPA 13 Table 19.2.3.1.2

Latest additions

An archive that grows with questions from the field.

The ten most recently published articles.

All articles Archive

Apps

Five iOS apps,
two web tools.

Five iOS apps that bring NFPA 13, FM Global, BS EN 12845 and BYKHY, plus duct and grille sizing, to mobile; two web tools for quotation management and cleanroom HVAC calculation. All apps

Fire standards, explained and calculated.

From clause to number, in one line.