Fire Protection in Server Rooms

Server rooms are the heart of a company’s information structure. They are extremely critical assets because the loss of data can be devastating and one of the most important objectives of a company is business continuity. 
The constant presence of the ignition source (electricity) and combustible material put at stake people’s life and costly business critical assets. About 6% of infrastructure failures in data centers are related to fire.
The average loss for a data center due to downtime is approx. $7,300 per minute or $609,500 for one downtime event
Using the wrong fire safety concept might lead to a higher financial damage than a fire itself can cause. Highly sensitive fire detectors are able to detect even the lowest smoke concentrations which may be caused by a malfunction of an electric or electronic element, for example. In the event of a fire, the fire protection system needs to react reliably and appropriately, triggering a coordinated alarm which leads people out of the danger area
and activates extinguishing systems. An automated extinguishing system can provide optimal protection for sensitive electronic equipment – with specially designed nozzles not impacting on computer hard disk drives and people safe, environmentally friendly extinguishing agents. 

Data centers and server rooms are at the heart of the modern
business world. Millions of servers worldwide process ever-increasing quantities of data throughout a global network of several billion devices. Losing  data can be devastating for companies ‒ the potential consequences range from losing money and damage to their reputations to having to close down. To keep up the unlimited availability of data is most important and in the event of a fire, the damage needs to be kept to an absolute minimum. Thus, keeping a data center safe from fire means ensuring business continuity. 
Server rooms in which IT infrastructure is housed, have to comply
with a higher security standard. They are designed in such a way: 
• That only authorized personnel can access the room, which prevents vandalism. 
• That the room is a separate fire zone and therefore there is no direct risk of fire from a           neighboring area. 
• That the room is air-conditioned according to system requirements. 
• That the central systems are connected to an emergency power supply. 

Basic conditions

Objective
• Detecting an unusual aerosol concentration and informing a technician so that
the situation can be tackled with most appropriate measures (e.g. controlled shut down of the device). 
• In the event of a significant aerosol development pointing to an incipient fire, damage has to be minimized, e.g. by shutting down the systems and extinguishing the fire with an automated extinguishing system.
• If there is a fire in the server room, the spreading of the fire to other areas must
be prevented. 
• Timely alarming and evacuating of all people at risk.  
• Safe extinguishing to protect delicate electronic equipment, people and irreplaceable data. 
Typical Fire Hazards 
• Overload or short circuit of electrical components (e.g. switch or inverter power supply). 
• Failure of the cooling system so that electronic components overheat considerably (e.g. power supplies and power electronics). 
Typical development of a fire 
In a server room that exclusively contains electrical and electronic components and devices, there is a very typical development of a fire.  
• If electrical or electronic components overheat, small quantities of aerosol are generated. If the power supply is disconnected in this phase, no fire will develop and damage can be kept to a minimum. 
• If the power supply is not disconnected, a smoldering fire will develop during which visible smoke is generated increasingly. If such a fire is detected in an early stage, it can be extinguished without problems and damage is can be kept to a minimum. 
• If no appropriate measures are taken, the smoldering fire will develop into an open fire which will cause significant damage.
 Critical points
• An increased aerosol concentration has to be detected before a smoldering fire starts.  
• During a smoldering fire, only a little amount of heat is generated, meaning the
aerosols do not spread throughout the whole room. 
• If the systems are cooled with increased ventilation, the aerosol concentration is diluted significantly by high air flows. 
• The extinguishing process must not cause additional damage (e.g. water damage, destruction of electronic appliances, harming of hard disks due to a high noise level during a discharge). 
• The fire has to be contained in the server room.

Solution

Maximum availability of an electronic data processing system is crucial. It is therefore recommended that the data center has the highest level of fire and security protection in the building. Very early fire detection plays an integral part in data center fire protection. With the help of very fast detection, operators can quickly be informed about an event and all required technical and organizational measures can be started immediately. Fire prevention is ideally based on the interaction of different elements, amongst others: fire detection, evacuation, extinguishing and building management systems to prevent the development of the fire. The following things are critical: very fast and reliable detection, avoiding false alarms and providing the exact location in order to assure an appropriate response, like reliable extinguishing of the fire. The fire safety concept with the corresponding response

procedures must always be defined in cooperation with the experts responsible for the data center. National fire safety guidelines and recommendations have priority over the Siemens guidelines. 

As the lowest aerosol concentrations have to be detected in such an area, an ASD (aspirating smoke detection) with very high sensitivity is recommended for fire detection. If local regulations stipulate a multiple zone dependency (simultaneous alarm signals across two zones in the same area), in addition to the ASD a sensitive smoke detector has to be used as a minimum. An ASD can cover several hundred square meters. In this way, the

server room can be monitored with one system. If additional point type detectors are required, their number and position will depend on the size of the room and the ventilation conditions. 

In addition to the automatic fire detectors, a manual release button is installed so that the extinguishing system can also be triggered manually. 

Automated dry extinguishing systems (i.e. systems using inert gases or clean agents) provide best protection for delicate and expensive electrical and electronic equipment in IT rooms. But as a hard disk drive is noise sensitive and can be disrupted by the release of the extinguishing agent into the flooding zone, Siemens recommends using Silent Extinguishing for reducing the noise level during a discharge in order to ensure data integrity. For more information on Silent Extinguishing, please refer to our Whitepaper on www.siemens.com/sinorix. 

The system design of automated extinguishing systems depends strongly on the size of the room and the structural conditions.