Data centers must delicately balance the need for infrastructure and equipment that runs all day and maximizes uptime with the need to manage heat and fire risk associated with electronic equipment. This is particularly true in server rooms. Server rooms are the heart of a data center, the hub of information. If a server room experiences a disaster of any kind, it typically leads to downtime. Server rooms must have proper air conditioning but that is not enough, they must also have appropriate fire suppression measures in place to reduce the risk of damage, injury, and downtime. There are many threats to data center operations but perhaps one of the most significant is fire. Other threats may pose a risk of significant downtime but are likely to only result in moments of downtime. Fire, on the other hand, can cause permanent damage to equipment, injury to personnel, and prolonged downtime as a result. When it comes to fire suppression in data centers, negligence to implement suppression is simply unacceptable – a true recipe for disaster.
The statistics surrounding fires in data centers may not sound all that scary at first glance – according to NetworksAsia, only about 6% of infrastructure failures are caused by fires. That kind of statistic may make you feel comfortable, like you do not really need to worry much about the risk of fire since you take appropriate precautions to ensure that your server rooms are cooled correctly. But, make no mistake, the risk is real and if it happens to you, it may not just lead to downtime, but to your data center closing its doors. Data Center Knowledge provides a wakeup call to all data centers about the very real risk of data center fires, “A small data center in Green Bay, Wisconsin was wiped out by a fire earlier this month, leaving a number of local business web sites offline. The March 19 fire destroyed 75 servers, routers and switches in the data center at Camera Corner/Connecting Point, a Green Bay business offering IT services and web site hosting…But it took 10 days to get customer web sites back online, indicating the company had no live backup plan…While the company discussed the usefulness of its fire alarms, it didn’t address whether the data center had a fire suppression system. But it doesn’t sound like it. The Green Bay Press Gazette describes “racks of blackened, melted plastic and steel.” We’ve previously looked at data center fire suppression tools and how they have evolved with the industry’s recent focus on environmental considerations.”
Fire prevention and fire suppression should be a part of any data center disaster recovery plan. It is important to consider what types of fire your data center is most at risk of, as well as the size of your data center, to determine the appropriate fire suppression system for your disaster recovery plan. Your data center’s form of backup and the specific strategies for your disaster recovery plan will heavily influence the type of fire suppression system that you use. If you have a minimal or “bare bones” disaster recovery plan, you may want the most elaborate and effective fire suppression system because you need it to work as effectively and quickly possible. If you have a comprehensive disaster recovery plan and robust backup/redundancy, uptime is less dependent on your fire suppression system. But, in the end, every single server room must have a fire suppression system that is more effective and comprehensive than “calling 911.”
To understand fire suppression needs and make an informed decision when choosing a fire suppression method, it is important that you understand what types of fires can occur in a server room or data center. TechTarget explains the types of fires data centers are at risk of:
“In North America, there are five fire classes:
- Class A: Fire with combustible materials as its fuel source, such as wood, cloth, paper, rubber and many plastics
- Class B: Fire in flammable liquids, oils, greases, tars, oil-base paints, lacquers and flammable gases
- Class C: Fire that involves electrical equipment
- Class D: Fire with ignitable metals as its fuel source
- Class K: Fire with cooking materials such as oil and fat at its fuel source
No matter where your data center is located, fire can be considered a potential disaster. Data center environments are typically at risk to Class A, B or C fires.”
There are two primary types of fire suppression systems: water sprinklers and gaseous agent fire suppression solution. Water sprinklers are a very traditional type of fire suppression system and they are the most common type. They are particularly popular because they are low cost, may already exist in the server room in the first place, and they are effective. Once they have been activated they will continue to expel water until they have been shut off. The main problem with water sprinklers is that they can cause significant damage to the equipment. With the goal of remaining operational and maximizing uptime while preventing catastrophic fire, dramatic water damage could still lead to downtime. Additionally, water sprinklers could accidentally become activated and cause unnecessary damage. And, while sprinklers systems are inexpensive, the water damage that they cause is not.
For this reason, many data centers and server rooms implement pre-action water sprinklers. Pre-action water sprinklers work in a similar way but take extra steps to prevent accidental activation and the ensuing damage. In traditional water sprinklers, the water is kept in the pipes, right at the nozzle awaiting activation. With pre-action water sprinklers, the water is not kept in the pipes all the way to the nozzle. The upside is that it is still a low cost system and traditional water sprinklers can be converted to pre-action systems. Pre-action systems require two events/alarms to activate the system, rather than one, significantly reducing the risk of accidental activation.
Gaseous agent fire suppressant solutions are a newer technology and are more effective in suppressing a wider and more significant range of fires. Gaseous agents are delivered in a similar fashion to water sprinklers – the agent is stored in a gas tank and then piped into overhead nozzles and administered when activated. This is the preferred method of fire suppression for server rooms because it is more effective at fire suppression when electrical equipment is involved. The Data Center Journal describes exactly how gaseous agent fire suppressant systems work, “The Inert Gas Fire Suppression System (IGFSS) is comprised of Argon (Ar) or Nitrogen (N) gas or a blend of those gases. Argon is an inert gas, and nitrogen is also unreactive. These gases present no danger to electronics, hardware or human occupants. The systems extinguish a fire by quickly flooding the area to be protected and effectively diluting the oxygen level to about 13–15%. Combustion requires at least 16% oxygen. The reduced oxygen level is still sufficient for personnel to function and safely evacuate the area. Since their debut in the mid 1990s, these systems have proven to be safe for information technology equipment application.” In essence, they are able to suppress fires while minimizing risk to electronic equipment. The problem with Halon gaseous agent use is that it is no longer in production due to being a health risk and environmental danger. But, there are Halon replacement agents available that work in a similar fashion without the risk to health or environment. Though more effective than sprinkler systems for certain types of fire suppression, and though they carry less risk of damage, they are more expensive and cannot run continuously until shut off. They will only run as long as the gaseous agent is available. Once the tank is empty – fire suppression will stop.
Server rooms pose the most significant risk of fire in a data center because they typically have the highest concentration of electricity and contain combustible materials. It is absolutely imperative that, should a fire be sensed, fire suppression begins immediately and alarms sound, alerting personnel that it is time to evacuate and take disaster recovery action. A server room is, at its core, the heart of a company’s information structure. If the server room experiences a fire, downtime is highly likely. But, if suppression methods are effectively and efficiently activated, downtime and damage maybe avoidable.