The prevention method starts with quickly finding the characteristics of the fire in the space and ends with extinguishing the fire. The use of rapid smoke detection systems that act as an active system is one of the solutions that engineers design as a prerequisite to prevent and spread fire in server rooms and data centers.
Among the disadvantages of using (Passive Optical Smoke Detection) systems, it is important that due to the depth of the type of fire formed in the PCB circuits of the system racks of the server room and data centers,The use of the above equipment, which is usually installed on the ceiling of the server rooms, is not recommended, and this is because of the long time spent on smoke detection and the overall prolongation of this process, causing more damage and eventually destroying each board. will be.
In the new active methods, a smoke suction system is used. This system uses pipes connected to it and holes that are installed on each channel ((pipe)) with special specifications, it sucks the ambient air into itself at any moment through the said holes and takes samples from them.
This sampling of very fine smoke particles with a size of about 0.005 Obs/m at any point that is being produced is detected by the laser chamber and transmitted through communication cables to the fire alarm panel that controls it and the alarm. or the flasher connected to it announces danger.
The mentioned systems are known as Air Sampling or Air Sampling Smoke Detection Apparatus. There are several ways to design pipes in server rooms or data centers.These pipes can be directed in the ceiling and in the vicinity of the rack, or connected to flexible pipes into the rack or even the UPS, in order to suck the air inside the environment and circulate the air inside the rack.By doing this, instead of waiting for the smoke to reach the ceiling, the fire alarm will sound in the pre-alarm phase at the same moment that the smoke has been produced.
In this case, smoke is detected by the system even at the stage when it is produced and is invisible. In the next steps, with the passage of time and the addition of the volume of smoke produced, higher alarm levels, such as Alarm 1 and Alarm 2, and finally the Action signal will be sent by the system for the final announcement or extinguishing evacuation.
An increase in temperature, short circuit in electronic circuits or power supply equipment, and consumption of more than allowed current can be mentioned as the causes of fire in the server room or data centers. Considering the sensitivity of network and computer equipment and their destruction at temperatures higher than the permissible limit, even when the fire has not spread to all points, the possibility of burning the electronic parts of the equipment is very high.
Since a large amount of cables are used in the server rooms and data centers, and because the cables are directly connected to other equipment at long distances, the fire can spread very quickly. In order to prevent the occurrence of fire due to cables, it is better to use linear heat detectors.
Basically, the cables are placed on the floor of the server rooms and on the cable trays. Linear detectors are laid on the cable trays in a sinusoidal fashion after the necessary engineering calculations on the computer network cables. Now, if the temperature increases illegally at any point of the network cables, the linear detectors or LHD directly sense the heat and send a signal to the fire alarm panel so that the relevant users can take measures to prevent the temperature increase.
Specialist design is considered not only in preventing fire, but also in extinguishing it quickly. Because in all conditions there is a possibility of fire and its spread in server rooms and data centers. Therefore, it is better to use a fire extinguishing system in addition to a suitable fire alarm system.
The noteworthy point is that water extinguishing systems cannot be used in these spaces, because if a fire occurs for any reason and water extinguishing is carried out, all electrical equipment will be seriously damaged or completely disabled. So, as a result, sprinkler water extinguishing system is not applicable in server rooms or database centers.
In the automatic fire extinguishing system, many existing gases, such as carbon dioxide or CO2, which act by removing an important fire factor, i.e. oxygen, are very dangerous for humans and cause suffocation. Therefore, halocarbon gases (FM 200) or pyrogen aerosol (Pyrogen Aerosol) should be used as a suitable extinguishing agent.
Halocarbons: HFC 125, HFC 227ea, HFC 123, FK-5-1-12
Inert Gases: IG01, IG100, IG55, IG54
Regarding the first two groups, i.e. HFC 125 and HFC 227 EA gases, comparisons can be made as follows. HFC 125 compared to HFC 227 EA:
· It has less weight. In an equal volume of space, less amount of gas is required. It benefits from a higher speed for gas distribution. Less space is needed to store cylinders. Less equipment and metal structures are used for installation.
A lower fee is paid for use in the project. Now, below we compare HFC 125 gas and Inert Gas to find out more advantages of HFC 125 gas. HFC 125 compared to Inert Gas:
· It has a variable volume of gas inside the cylinders.
In this way, the volume of inert gas inside the cylinder cannot be adjusted with the space to be extinguished. It has a lower operating pressure. In Inert Gas, a pressure equal to 200 bar is needed to discharge the gas, while this number is 125 times 52 bar for HFC gas.
Cheaper tools are used because they don’t need a lot of pressure tolerance, so the consumables for the construction of the side equipment of this system have a lower pressure tolerance coefficient and the consumable metals have a thicker thickness.
· In an equal volume of space, it uses less number of cylinders (about half).
So, as a result, it occupies less space in the project. It has a lower maintenance cost. The annual repair and maintenance cost of the HFC 125 system is about 3% of the supply cost, while this cost for the inert gas extinguishing system is about 5%.
But the best system that can be used in server rooms is pyrogen aerosol gases, which we will compare with the above gases below:
. The ability to extinguish all fire classes without the need for plumbing
. Without pressure tanks and the possibility of explosion
. Non-toxic and without reducing the oxygen level during fire extinguishing
. High ventilation in the environment for up to 1 hour to prevent the fire from re-igniting
. No corrosive effect at high temperature
. without causing damage to the equipment
. Completely environmentally friendly
. It has the highest impact factor in relation to volume
. Without any possibility of leaks, drips and pressure drop
. Zero electrical conductivity even in strong fields. Invulnerability to vibration and impact