Data Centre fire detection and suppression systems
Building a data centre is a considerable investment and populating it with racks, servers, and all the other necessary equipment is a major one. Fire detection should be at the top of your list when it comes to protecting your new asset. Today, the vast majority of data centres, computer rooms and server rooms are regarded as ‘lights out’ facilities and infrequently entered. Therefore it is imperative that the equipment is protected by monitoring the environment for fire.
You need to consider Fire detection systems with multiple detection heads as your minimum requirement. The system should consist of ionisation and optical detection covering the space and any floor or ceiling voids. It should preferably be a standalone system linked to the ‘house’ fire alarm and should incorporate controls to shut down supporting services and plant on 1st and 2nd stage fire alarms. You should also consider an Extinguishing system to work in conjunction with the detection system.
Gas or Water
Extinguishing systems fall into two basic types – water based and gaseous or ‘Clean Agent’ systems. Clean Agent systems are generally preferred for IT environments as they will not damage the equipment and require no cleaning up in the event of a discharge. There are two types of Clean Agent – inert gases such as nitrogen, argon and carbon dioxide and the active gases such as FM 200 and FE 25.
Which Gas
The inert gases are often used in combination and are marketed under various trade names such as Argonite and Inergen. They work by displacing the oxygen while the active gases work by interrupting the chemical chain reaction of combustion and by removing heat.
There is much debate between the manufacturers of the different gases as to which are most effective and which are least damaging to the environment although it must be pointed out that all gases now supplied are classed as having Zero Ozone Depleting Potential (ODP). The argument in favour of the inert gases is that they are naturally occurring while against them is that they require 3 to 4 times as much gas to do the job and therefore require more cylinders, more space and are consequently more expensive. The active agents have the advantage of being faster acting and requiring much less gas but are synthetic and so there could be concerns about their release into the atmosphere.
All classes of Clean Agents are safe to breath and, once discharged, extinguish the fire rapidly and leave no residue and in general the decision as to which one is used comes down to the client’s preference.
Early Warning Systems
High Sensitivity Smoke Detection (HSSD)systems are 100 to 200 times more sensitive than conventional smoke detectors and detect combustion at the incipient stage, i.e. before fire breaks out. They can save thousands of pounds by enabling early action to be taken, preventing a fire and thus avoiding damage and the cost of having to replace the suppression gas after a discharge. They are used in addition to a basic detection system for warning only as their sensitivity can make them vulnerable to false alarms. The best known are VESDA and HART which are aspirating (ASD) systems and work by continually drawing air from strategic points in the data centre then passing it through a laser detector. VIEW systems have numerous detectors distributed around the room connected back to a central controller.
Phoenix Optics can advise on what is the best fire detection, warning and suppression system for your data centre then plan, install and maintain the system to meet your budget and operational needs.