To protect various buildings or structures from fire, fire water pipelines are installed. Inside the task, a fire hydrant is equipped, to which a fire-fighting water supply is connected. According to the requirements of SNiPP-30-76, fire water pipelines with fire hydrants are installed in residential multi-storey buildings.
Fire hydrant equipped with:
- a fire valve with a diameter of fifty or sixty millimeters, attached to a branch of the riser;
- hose (hemp sleeve) 10-20 m long;
- quick-closing semi-guns;
- a fire nozzle with a spray (tip) with a diameter of 13 mm, (and can also be a diameter of 16, 19, 22 mm).
The fire hydrant is placed at a level of 1.35 m from the plinth in special cabinets labeled "PC". Paired cranes are placed one above the other at a distance of one meter above the plinth. Like all firefighting equipment, the location of these items is indicated on the fire safety plan. A special sign is placed nearby: a white fire hydrant on redfield.
If there are more than twelve fire hydrants in the fire water pipeline network, they are looped and connected to the networks with two or more inputs. The number of products is determined by the irrigation area of all rooms in the building. The radius of the crane is calculated by the formula: R=L1+L2, where R is the fire hydrant impact radius, L1 - the length of the sleeve (hose) of the fire hydrant;
L2 - the level of the compact part of the jet, equal to the height of the room in which the fire hydrant is installed, but not less than six meters in buildings whose height does not reach 50 m, and not less than eight meters in buildings over 50 m high.
Table 1. The lowest water consumption for extinguishing a fire inside a building
| Buildings and premises | Least water consumption per tap, l/s | Number of fire hydrants per floor | |
| Residential buildings | Corridor length up to 10 m, number of floors 12-16 | 2, 5 | 1 |
| The length of the corridor is more than 10 m, the number of floors is 12-16 | 2, 5 | 2 | |
| Corridor length up to 10 m, number of floors 16-25 | 2, 5 | 2 | |
| The length of the corridor is more than 10 m, the number of floors is 16-25 | 2, 5 | 3 | |
| Administrative buildings | Building capacity up to 25,000 cu. m., number of floors 6-10 | 2, 5 | 1 |
| The volume of the building is over 25,000 cubic meters. m., number of floors 6-10 | 2, 5 | 2 | |
| Building capacity up to 25,000 cu. m., the number of floors is more than 10 | 2, 5 | 2 | |
| The volume of the building is over 25,000 cubic meters. m., the number of floors is more than 10 | 2, 5 | 3 | |
| Public buildings and hostels | Number of floors up to 10, building volume 5000-25000 cubic meters. m. | 2, 5 | 1 |
| Number of floors up to 10, building volume over 25,000 cubic meters. m. | 2, 5 | 2 | |
| The number of floors is more than 10, the volume of the building is 5000-25000 cubic meters. m. | 2, 5 | 2 | |
| The number of floors is more than 10, the volume of the building is over 25,000 cubic meters. m. | 2, 5 | 3 | |
| Administrative and amenity industrial buildings | Building volume 5000- 25000 cu. m. | 2, 5 | 1 |
| The volume of the building is over 25,000 cubic meters. m. | 2, 5 | 2 | |
The radius of impact of a fire hydrant should not be less than sixteen meters (buildings below 50 m) and twenty-six meters (buildings above 50 m). On the floor, fire hydrants are mounted in such a way that any point in the room can be irrigated with jets from at least two devices. The number of simultaneously functioning fire hydrants and the lowest water flow can be seen in table 1.
When using devices at the same time, a twin crane can be installed on one riser. The fire valve is mounted with a diameter of 50 mm. One jet of water requires 2.5 l/s or 5 l/s, the number of jets acting together should notexceed eight.
