How to prevent valuable data in a server room from going up in smoke
The installation of proper fire detection and suppression systems is critical in hi-tech areas such as server rooms to protect both costly equipment and valuable data in the event of any fire, comments ASP Fire CEO Michael van Niekerk. “More often than not it is the data and equipment you want to preserve.”
Fire detection in such a critical environment must account for many factors, from the actual value of the equipment and the data it contains, to the potential sources of ignition, which includes the presence of electricity.
Here a gas fire-suppression system is the best option due to the sensitivity of the equipment. “Obviously, a sprinkler or water-mist system is not really ideal due to the presence of electricity,” van Niekerk explains. “You want to ensure you are putting in a suppression medium that is not going to create more damage than the fire itself.”
In terms of gas fire-suppression systems, there are several options. The first is to flood the server room with an inert gas such as Carbon Dioxide Gas (CO2), Argonite (IG-55), comprising argon (50%) and nitrogen (50%), or Inergen, a mixture of nitrogen (52%), argon (40%), and carbon dioxide (8%). Clean, safe gases such as FM 200 or NOVEC 1230 will not cause any damage to HDDs and they will not cause any noticeable adverse effects on humans at the design concentration.
The CO2, Argonite and Inergen systems are high-pressure systems that flood the interior to a 60% concentration of the gas in question. “The problem, of course, is that if you have human occupants still inside and they cannot escape quickly enough, they will succumb to asphyxiation,” warns van Niekerk.
Therefore, a key element of any fire-suppression system for a server-room environment is that, in the event of a system discharge, any occupants receive sufficient warning to escape, with a corresponding delay in the actual activation of the system itself.
Another issue that has to be taken into consideration is the potential damage that can be caused to such equipment itself by these high-pressure systems, which can operate at up to 300 bar. A related issue is damage due to thermal shock, as the equipment runs at a high temperature, and then cools down so rapidly it can be damaged in the presence of the much colder, high-pressure gas.
High-pressure systems are traditionally a third to double the price of low-pressure clean-gas systems. Here FM-200 is a popular option, a colourless, odourless gaseous halocarbon. These systems also operate at a much lower pressure of 20 to 25 bar. Anything above 50 bar is considered a high-pressure system. “You actually need to be certified by the Southern Africa Compressed Gases Association (SACGA) in order to be able to work on these systems,” adds van Niekerk.
FM-200 is deemed a clean, safe gas as it leaves no residue. It reduces the oxygen level in the server room to about 12% from a normal 23%, too low for a fire to be sustained but allowing humans to breathe long enough to evacuate.
The challenge posed by server rooms is that they often feature sunken floor voids or a roof void with a suspended ceiling to accommodate cabling. These volumes also need to be filled with gas, or the required concentration will not be achieved. Therefore, the volume of space in a server room can be much larger than anticipated, which means more careful planning is required.
An in-cabinet system instead discharges gas into the server cabinet containing the server itself, as opposed to filling up the entire room. Here a common gas is Novec 1230, a low Global Warming Potential (GWP) halon replacement. An alternative is Pyroshield, a mixture of nitrogen and argon. However, an in-cabinet system does not account for other potential ignition sources such as distribution boards or Uninterrupted Power Supply (UPS) units.
The size of the server room and the equipment installed in the room determines the type of solution opted for, especially of there is a UPS installed in the room. Server rooms are required to be constructed from fire rated materials so that a fire does not spread from within the room or from the surrounding area into the server room. ASP Fire can conduct a full fire-risk assessment in any server-room environment to derive at the optimal fire detection and suppression solution.
In terms of fire-detection equipment in server rooms, van Niekerk recommends a monthly service inspection, as the building maintenance team often does not have the time to carry this our properly. “We activate the detectors to ensure they are all in proper working order and check all components such as solenoids so that the activation system is deemed 100% operational,” concludes van Niekerk.
