Integrated fire safety solutions for data centres

IN THE DATA CENTRE INDUSTRY, the main concern is business continuity. In other words, companies rely on their information systems to run their operations. If a system becomes unavailable, company operations may be impaired or stop completely. It is therefore necessary to provide a reliable infrastructure for data centre operations in order to minimize any chance of disruption. Information security is also a concern, and for this reason a data centre has to offer a secure environment which minimizes the chances of a security breach.

A data centre must maintain high standards to ensure the integrity and functionality of its hosted computer environment. In addition, it has to be designed, implemented and operated in such a way that a high level of availability (business continuity) can be guaranteed. This means an error-tolerant IT environment with redundancy and maximum availability of 99.995% per year.

Perfect interaction
The most important objective in a data centre is maximum availability (99.995% per year). Simply put, the central task of a fire safety system is to keep the business going even in case of a fire. Early detection plays an integral part. This is because the earlier a fire can be detected, the earlier the operators can be notified of the event and the earlier the required technical and organizational measures can be initiated.
Furthermore, analyses show that a major cause of fire safety failure is the interface between detection, alarming, control and extinguishing. For this reason, perfect communication between all products is essential for the effectiveness of the complete system. In other words, an integrated fire safety system from a single source is crucial for success.

Early, reliable detection is key
Heavy power loads or a defective component in data centre equipment can quickly lead to overheating or a short circuit. A typical fire will start slowly with a long period of overheating and smouldering before erupting into flames. To detect overheating and avoid the onset of flames, very early smoke detection is required. If smoke is greatly diluted by high ventilation, aspirating smoke detection (ASD) will provide the earliest possible warning even when the smoke is barely discernible to people. Air samples are continuously taken at the danger spots, usually in the circular airflow as well as among the server racks, and carried to the sampling device. As soon as smoke particles are detected by the air sampler, a pre-alarm or an alarm is triggered, depending on the smoke concentration. The response characteristic is determined according to the application. Sensitivity ranges from normal to high, allowing even a minimal smoke concentration to be identified unequivocally at an early stage. This saves valuable time needed to clarify the cause and take countermeasures, such as cooling system deactivation, gentle shut-down, data export and selective shut-down.
Shutting down equipment at the earliest indication of fire will stop even corrosive combustion gases from developing further. In a “gentle” shutdown, intelligent server management is activated to divert valuable data to neighbouring server racks. This can only be achieved by combining an appropriate software/hardware environment with the earliest possible fire detection. The final shutdown of power only takes place when the transfer of data is complete.

If such a “gentle” shutdown is considered too risky, an alternative method – aspirating smoke detection with verification by point-type detectors – may be used. In this system, the cooling system is shut down after pre-alarm while the point-type detectors verify the presence of combustion and triggerthe extinguishing system.

As pioneer in detection engineering, Siemens has developed a highly reliable ASD. This new product uses a dual wavelength technology to verify that particles aspirated in very low concent rations are smoke from a fire. Full integration of the device into the fire safety or management system ensures the safest operation possible because all the ASD warnings and possible maintenance messages are available at the management level so corrective measures can be taken.

Safe and quiet extinguishing to prevent damage to HDDs
in operation
The most important factor when designing an extinguishing system in a data centre environment is to make sure that the chosen agent extinguishes the fire without harming sensitive electronic equipment. For this reason, water should be avoided at all times. Furthermore, the agent must be environmentally friendly, safe for people working in the protected area, and not harm the HDDs in operation.

Even though dry extinguishing systems are the best choice to protect data centres, the latest technological findings show that in very rare cases computers and HDDs can face problems after the extinguishing process has been triggered. These problems may range from automatic shutdown of an HDD with no damage after restart to more severe disturbances. It was found that the main cause of these problems was the high noise level caused by the discharge of the agent during the extinguishing process.

To answer this challenge, Siemens developed the unique Sinorix Silent Extinguishing Technology, which includes two solutions to ensure quiet and safe extinguishing in data centres and server rooms. This technology reliably protects IT operations and minimizes the risk of business interruptions following a fire extinguishing system discharge.

The heart of the technology is the Sinorix Silent Nozzle. To reliably protect smaller server rooms, it was combined with other high-quality components into Sinorix Compact - an ideal and cost-effective all-in-one fire safety system. Sinorix Compact optimally protects small server rooms up to 120 m3 and is easy to install, commission and maintain. The Sinorix Silent Nozzle also ensures optimized quiet extinguishing in medium to large-sized data centres when paired with the Sinorix CDT (Constant Discharge Technology) extinguishing system. It can be dimensioned as a single- or multi-sector system, and the cylinder battery can be positioned either centrally or decentrally. Furthermore, Sinorix CDT is suitable for interior rooms with structural restrictions because the size of the overpressure flaps can be reduced by up to 70 percent.

Sinorix Silent Extinguishing Technology offers extinguishing agents that are safe for people, delicate electronics and the environment. Sinorix Compact uses the Novec 1230 fluid, a clean chemical agent that is non-corrosive and non-conductive.

It has an ozone depletion potential of 0, a short atmospheric life of 3 to 5 days and a global warming potential of 1. Sinorix CDT uses the natural gases nitrogen and argon, which are naturally present in the ambient air. They have poor electroconductive properties, are chemically inert and do not create any harmful reaction products.

Complete fire safety from a single supplier
To ensure the highest possible fire safety, it is important to control the interfaces and use the latest scientific findings for the best solution. Having a complete fire safety system from a single supplier guarantees that all the interfaces are tested and installed in millions of applications. Siemens offers a complete portfolio with a variety of options for detection, alarming, control and extinguishing. In addition, the interfaces use standardized industrial protocols (e.g. BACnet) that are open and safe at the same time.