What are requirements for tubs and tanks storing water for outdoor firefighting in Vietnam?

Pursuant to Section 5.1.5 of the national technical regulations on fire safety for buldings and constructions issued together with the Circular 02/2021/TT-BXD stipulating requirements for tubs and tanks storing water for outdoor firefighting in Vietnam as follows:

1. Functions of tubs and tanks providing water must include circulating, firefighting, occurring of incidents and containing of feed water.

2. If collection of water for firefighting directly from water sources does not conform to economic and technical conditions, tanks and tubs must contain adequate calculated amount of water for firefighting.

3. Volume of water in tanks and tubs must be calculated so as to ensure:

- Provision of water for firefighting from outdoor hydrant boosters and other fire suppression systems;

- Provision of water for specialized fire suppression devices (sprinklers, drenchers, etc.) that do not have separate tanks.

- Maximum water amount for daily routines and manufacturing during firefighting process.

4. Reservoir providing water for fire engines must have access and parking lots with dimensions of no smaller than 12 m x 12 m and surfaces capable of withstanding load of fire engines.

NOTE: When determining volume of water for firefighting in tubs and tanks, may take into account refilling the tubs and tanks during firefighting process in case of water supply systems satisfactory to 5.1.2.7.

5. When supplying water via 1 pipeline, prepare back up water for firefighting, the amount of water shall conform to 5.1.5.3.

NOTE: May not take into account the backup water if the length of a supply pipeline does not exceed 500 m in a residential area with less than 5 000 people and entities requiring no more than 40 l/s of water for outdoor firefighting.

6. Total number of tanks and tubs for firefighting in a pipe network must not be less than 2 (does not apply to tanks and tubs for outdoor water supply of independent structures).

The minimum and maximum level of water for firefighting among all tubs and tanks in the same network must be the same.

Upon shutting a tank or tub, the amount of water for firefighting stored in other tubs and tanks must not be less than 50 % of the amount of water required for firefighting.

7. Storage of water in tubs and tanks or exposed tanks is permitted in case of:

- A residential area with up to 5 000 people.

- Buildings, regardless of purposes, situated separately outside of residential areas having no pipe networks for supplying water for daily routines or manufacturing and for supplying necessary water amount for outdoor hydrant boosters.

- Multi-purpose buildings requiring no more than 10 l/s of water for outdoor firefighting.

- Buildings with 1 to 2 storeys, regardless of functions, having construction area no larger than area of fire compartments applied to the building types.

8. Amount of water for firefighting of tubs, tanks and man-made reservoirs shall be determined based on calculation of amount of water consumed and duration of firefighting according to 5.1.2.2 through 5.1.2.6 and 5.1.3.3.

NOTE 1: When calculating volume of water for firefighting of man-made reservoirs, must take into account possibilities of evaporation and freezing of water. Minimum water level must not be less than 0.5 m.

NOTE 2: Must ensure access for fire engines.

9. Tanks, tubs, outdoor hydrant boosters, natural and man-made reservoirs for firefighting must be situated within following radius:

- 200 m in case of pump trucks.

- 100 m to 150 m within technical operation range of mobile pumps in case of mobile pumps.

- In order to increase operation radius, may install dead end pipes no longer than 200 m from the tanks, tubs and man-made reservoirs satisfactory to 5.1.5.8.

- Distance from points of collecting water in tanks, tubs or man-made reservoirs to buildings with fire-resistance category of III, IV and V or to exposed warehouses containing flammable materials must not be less than 30 m, to buildings with fire resistance category of I and II must not be less than 10 m.

10. If unable to suck water for firefighting directly from tanks, tubs or reservoirs by pump trucks or mobile pumps, provide basins with volume ranging from 3 m³ to 5 m³. Diameter of pipes connecting tubs, tanks or reservoirs with the basins shall be calculated based on factors of calculating water flow rate for outdoor firefighting but no less than 200 mm. Valve boxes must be installed on pipelines to lock water circulation, closing and opening of valves must be performed from the outside of the boxes. The pipe ends located in man-made reservoirs must be installed with sieves.

11. Pressure tanks and tubs for firefighting must be equipped with water level meters, devices reporting water level to pump stations or water distribution stations.

Pressure tanks and tubs of high-pressure pipelines for firefighting must be equipped with devices that automatically stop water from being carried to tubs, tanks and water towers when firefighting pumps are operating.

12. Pressure tanks and tubs that use pressurized compressed air must have back up pressurizing machines in addition to active pressuring machines.

Best regards!