Local Applications

Instead of protecting an entire data facility, fire suppression systems can be built to protect a smaller, localized part, or specific equipment inside the area. This saves money over building an entire total-flood suppression system.

Local targets within a Data Center can include areas with potential fire sources, such as HVAC, power and communication cables (often located in subfloors or above floor cable trays) and power rooms (including backup generators, UPS, and battery rooms).

During the design and installation of a localized water mist system, closed, fusible-link, discharge heads must be carefully chosen and positioned to provide maximum coverage. Calculations should include consideration for activation temperature, flow, and distribution patterns for the concerned area. In the event of a fire, the system should only deploy water mist in the spaces where a heat signature is detected.

Many Data Centers prefer to deploy inert gas fire suppression systems. Generally, these systems protect extremely expensive gear. High-end computers, for example, are far more costly to replace than standard X86 servers. In practice, inert gas fire suppression systems replace the water via sprinkler nozzles. The discharge from an inert gas system, however, has also been shown to damage Data Center servers. Inert gas systems are far superior for protecting IT equipment because they do not compromise electronic circuits, even under full operation. In addition, inert gas systems can extinguish deep-seated fires, including those inside the racks.

Sellers of the system have worked to improve the delivery system for the release of the inert gasses by redesigning nozzles and improving sensors to reduce false signals. The Uptime Institute agrees that improvements have been made.

 

Recommendations From Vendors Regarding the Use of Inert Gas Systems:

  • Installing racks that have doors to muffle the noise
  • Installing sound-insulating cabinets
  • Using high-quality servers, or solid-state servers and memory
  • Slowing the rate of inert gas discharge
  • Installing walls and ceilings that incorporate sound-muffling materials
  • Aiming gas discharge nozzles away from servers
  • Removing power from IT gear before testing inert gas fire suppression systems
  • Muffling alarms during testing
  • Replicating data to off-site disk storage

 

Despite improvements of inert gas fire suppression systems, pre-action fire suppression (which are water-based or carbon dioxide) systems have become more common. The use of water means that facility owners are insured against the total loss of a data center, and the dry-pipe feature—protects facilities from an accidental discharge in white spaces. It is because they are more economical choices, especially as local codes and ordinances require the use of a water suppression system, whereas the inert gas system is a fairly expensive back-up option.

Still, inert gas fire suppression systems have some followers, and they may make business sense for some companies. Data Center operators can use inert gas applications where water is scarce, or when a Data Center has very expensive and unique IT gear, such as supercomputers in HPC facilities, or old school tape-drive storage. In these instances, it is prudent that organizations would be better off developing improved backup and business continuity plans.

Those Centers considering inert gas suppressions are happy to learn that vendors have made considerable revisions to minimize damage from discharges of inert gas, and improved sensors that register fewer false positives. In addition, they have developed stricter procedures to minimize inadvertent discharge due to human error, which is the most common cause of accidental discharges.

It is recommended that IT management teams work with risk managers to make sure that all stakeholders have an understanding of a facility’s fire suppression requirements and alternatives before choosing a fire suppression system. Operational considerations should also be included so that the system is fitted to an organization’s risk exposure and the business requirements.

 

Conclusions

Most Data Centers should take advantage of a combination of pre-action (dry pipe) sprinkler system and high-sensitivity smoke detection. Most authorities having jurisdiction (AHJs), risk managers, and insurance companies will agree with this choice as long as other operating requirements are met, such as having a highly-trained staff providing building safety protocols. Local and government safety agencies are quite familiar with water-based fire suppression systems, as they are used by a vast majority of installations in the U.S. They may not, however, always be well-versed with pre-action systems.

Finally, Data Center operators should regularly examine their fire suppression systems and remove inert gas systems from spaces where sensitive equipment is no longer located. Deploying the system where it is no longer needed is no longer practical.

Reference links:

http://news.tmcnet.com/topics/articles/2020/03/02/444640-challenges-fire-suppression-a-data-centre-environment.htm

https://journal.uptimeinstitute.com/fire-suppression-systems-bring-risk/

https://www.missioncriticalmagazine.com/articles/93098-data-center-fire-suppression