You have decided to install a gas extinguishing system to protect one of the rooms in your building against fire hazards.
A suitable system was determined and the system design was completed according to the standards. The design was verified with the hydraulic calculation software. Then it was installed and commissioned completely. However, the system failed to extinguish the fire.
The most important reason for the failure of the extinguishing system in the areas protected by the gas extinguishing system is the openings that were not prescribed during the design. In case of fire, the escape of the extinguishing gas discharged into the area through these openings often causes failure to extinguish the fire. To make sure that the system will work, these openings must be closed and the area must be sealed. The sufficiency of the sealing of the area is determined by conducting the Room Integrity Test.
To understand the problem clearly, first of all, the working principle of the gas extinguishing systems that protects the area should be known.
In the gas extinguishing systems that protect the area, there is a relationship between the extinguisher concentration, the height of the protected devices and the duration of the protection. Extinguishing gas stored in pressurized cylinders is discharged into the area through nozzles at the time of fire. After the fire is contained, the gas must be kept in the area for a particular time to prevent sparks. However, this criterion is not sufficient alone. The gas concentration at the highest point of the fire-protected devices must be able to maintain the minimum design concentration at the end of this period as well. If these conditions are fulfilled, it is accepted that the system is able to protect the area against fire; otherwise, it cannot.
The most significant factor that prevents the formation of these conditions is the openings available in the area. Some of the gas discharged with a certain pressure escapes through these openings. Such openings can be large in size, such as cable passages, or they can be small in size and can be found at the overlooked points.
Room integrity tests must be conducted to determine whether the seals will prevent the gas extinguishing system from operating. The test principle is based on the negative and positive pressures created by all gas extinguishing systems at the time of discharge. It is understood whether the sealing is sufficient or not by first increasing the pressure of the protected room, then decreasing the pressure and assessing the information obtained according to the standards.
The following devices are used when conducting the test:
The portable door frame is installed on a suitable door opening into the room, and the fan is placed on the frame. After the meters are installed, the fan is connected to the power supply. The type of extinguishing gas, volume information and design standard of the system are entered into the test software. The room is pressurized with the fan, and the meters are read. The same process is repeated to reduce the pressure of the room by reversing the fan. When the readings are entered into the test software, the prescribed residence time of the gas in the room is obtained.
The TS ISO 14520-1 standard requires that this test should be conducted at least once per year for the areas protected by the gas extinguishing system. It is also mandatory to repeat this test after making any modifications in the room.
In the gas extinguishing systems designed for protection of areas, room integrity is as important as the system design. Neglecting the room integrity tests means that you have no assurance of fire protection. Our company conducts room integrity tests with certified specialized staff and calibrated devices. Contact us now to make sure that your facility is protected against fire with gas extinguishing systems.
