Fast deliveryNationwide
Factory pricesDirect from the mills
Free advice / ZaloQuote in 5 minutes
Hotline / Zalo0933 160 169
VIENZHJAKO
Fill in once; every calculator uses it and prints it with the results. Stored only on your device.

Indoor fire hydrants: jets and flow

Choose the building type and enter floors, height and volume. The tool looks up the simultaneous fire jets, flow per jet, valve size, minimum compact jet and water reserve.

Updated Technical review: KS. Dương Văn TiếnFree, no sign-up
Quick answer

Production buildings, warehouses: 2 jets × 5.0 L/s = 10.0 L/s. DN65 valve, compact jet ≥ 6 m, 1-hour water reserve 36.0 m³.

Inputs

fl.
m
Ground to top floor level
m³
Length × width × height, or from the design file

Enter your data, then press Calculate (or Enter).

Preliminary results

Jets × flow2 × 5.0L/s
Total flow10.0L/s
ValveDN65
1-hour water36.0m³
StepResultBasis
Table lookupProduction buildings, warehouses2 × 5.0 L/sTCVN 3890:2023 bảng 12 ⚠
Total flow2 × 5.010.0 L/s—
1-hour reserve3,6 × 10.0 × 1 h36.0 m³TCVN 3890:2023 ⚠
Valve, hose sizeq = 5.0 L/s > 4DN65QCVN 06:2022/BXD 5.2.7 ⚠
Minimum compact jetH = 12 m≥ 6 mQCVN 06:2022/BXD 5.2.7 ⚠
Preliminary riserQ = 10.0 L/s, v ≤ 3 m/sDN65—
  • Every point must be reached by the required jets; max 2 jets per cabinet.
  • Valve centre 1.20 m ± 0.15 m above floor, at stair lobbies, corridors, exits.
  • More than 12 hydrants or an automatic system: ring main with at least 2 supply lines.
  • Buildings of 17+ floors: a fire-brigade inlet per zone.
Sources and assumptions. Jets and flow per TCVN 3890:2023 Table 11 (residential, public) and Table 12 (production, warehouses), inherited from TCVN 2622:1995; car parks per QCVN 13:2018/BXD; compact jet and valve size per QCVN 06:2022/BXD 5.2.7; 1-hour reserve for a stand-alone hydrant system ⚠. ⚠ = code table value to be checked against the original standard. Preliminary results for material selection and budgeting; not a substitute for an approved fire protection design.

Suggested materials

Fire hydrant angle valve DN65per drawing
DN65 fire hose 20 m + nozzleper drawing
Fire hose cabinet (valve, hose, nozzle)per drawing
Galvanised steel riser pipe DN65per drawing

Jets × flow (L/s) for production buildings, warehouses

Fire resistance · class0.5–55–5050–200200–400400–800 thousand m³
I, II · A, B, C2 × 2.52 × 5.02 × 5.03 × 5.04 × 5.0
I, II · D, ENot requiredNot requiredNot requiredNot requiredNot required
III · C2 × 2.52 × 5.02 × 5.0Special designSpecial design
III · D, ENot required2 × 2.5Special designSpecial designSpecial design
IV, V · C2 × 2.52 × 5.0Special designSpecial designSpecial design
IV, V · D, ENot requiredSpecial designSpecial designSpecial designSpecial design

Outlined cell = applied cell. "Special design": outside the table, calculated by the designer.

Next: fire water tank + pumps →

Frequently asked questions

How many hydrant jets does a factory need?

A grade I–II, class C factory of 5,000–200,000 m³ needs 2 jets of 5 L/s each (DN65 valves). The number of cabinets depends on the layout: every point must be reached by 2 jets with 20 m hoses.

When DN50 and when DN65?

Up to 4 L/s per jet (usually 2.5 L/s) use DN50 valves and hoses; 5 L/s jets use DN65.

Does a cold-machining workshop need indoor hydrants?

Grade I–II production buildings of class D or E do not need indoor hydrants per the table, but still need outdoor fire water and extinguishers.

ZaloChat on ZaloOrder hotline0937 664 114