FireSafetySupplementXtralis October2016_PSI_may15 10/10/2016 16:05 Page 2
FIRE SAFETY
Major Data Centre providers are looking towards colder countries to reduce power and cooling costs, meaning that the UK and Ireland (among other countries) are enjoying an even greater status as homes for these facilities. That’s the view of Jim Thompson, regional manager for the UK and Ireland at Xtralis
Xtralis is working with all the global leaders in the Data Centre industry to ensure that the legislated design principles are adhered to and the best equipment is specified in order to create efficient, reliable and costeffective solutions. More information on the use of VESDA in Electronic Data Processing areas can be found at: www.xtralis.com/ applicationbrochures
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VESDA: Addressing Smoke Detection Challenges in Data Centres election of location ties directly to transitions in terms of cooling strategies largely driven by two factors: increased heat loads and lower PUE (Power Usage Effectiveness), where the total power being used is compared to the actual power used for the computing equipment itself. The objective is the ratio is as low as possible. From a fire detection perspective, cooling strategies and innovations continue to evolve, with many configurations outpacing prescriptive requirements and capabilities of traditional detection technologies. Fire detection design is often further confused by blue chip service providers constructing standardised facilities in multiple countries with varying fire protection codes and standards, but at the same time wanting a standardised design concept. In the UK, we’re very accustomed to BS 5839, but perhaps our knowledge of BS 6266 Fire Protection for Electronic Equipment installations is somewhat lacking. Additionally, many of the larger providers invariably have a requirement for compliance with NFPA 72 (similar to BS 5839) and NFPA 76 (similar to BS 6266). To further complicate matters, Ireland has its own IS3218 standard which is almost identical to BS 5839, but has no specific electronic data processing standard at all. The airflow distribution path plays a significant role in terms of smoke detection placement. During the incipient stage of fire development, which is ideally the best time to detect an impeding fire, smoke being diluted and having little thermal energy is buoyant and highly influenced by airflow. The key to smoke detection in areas subject to forced air cooling is placement within the airflow distribution path at a point where smoke is likely to intersect the sensor or port prior to leaving the compartment, such as at return air grilles or within air containment aisles. In over 90% of tested facilities, detection within the airflow distribution path is first to respond. In a fullyfunctional
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Data Centre, it’s actually very often the only detection that responds. So why VESDA? When properly implemented, Aspirating Smoke Detection (ASD) uniquely addresses detection challenges, providing effectiveness in terms of performance and cost. ASD, but much better known as VESDA, enables a much more sensitive detection level or levels. It can work effectively in high air velocity environments and actively draws air/smoke into the detector. Additionally, ASD benefits from a cumulative effect (ie a small amount of smoke enters more than one sampling point on the pipe, meaning a larger sample of smoke is taken and enables diluted smoke to be detected more easily). The aforementioned standards recognise this and most Data Centre facilities will be categorised as high or critical risk. Correct specification of fire standard and risk category of these facilities would ensure that High Sensitivity Smoke Detection is installed to monitor airflow distribution paths, thereby giving effective detection. It’s also recommended that detection spacing across the ceiling is decreased, typically to 25 sq/m per detection point/sampling hole. It’s important that this principle isn’t overlooked. As an industry, we need to be more aware of and drive acceptance of these more specialised (but now increasingly common) standards. Xtralis has striven for many years to promote a very early warning performance-based detection philosophy through CPD courses and regular VESDA-accredited training courses. The ASD industry has taken great steps forward in recent years. Xtralis has been the pioneer and market leader for many years, with the widest portfolio and global experience. The latest VESDA technology innovations allow us to not only identify smoke, but also work towards identifying what type of particles are being produced. This is enabled by the patented Flair technology in the VESDA E Series range of detectors. This technology not only opens a world of future possibilities for the way in which we look at smoke detection, but also drastically reduces the risk of false alarms while still providing the highest possible level of detection.
www.risk-uk.com