Sprinkler systems computer rooms

Some authorities having jurisdiction require sprinklers below the operating floor even when the plenum is 2 or less. This is not a proven practice. Tests were performed in Europe to determine the acceptability of sprinklers below computer room floors. They proved to be ineffective and much better protection was provided by gaseous extinguishing systems. There is a fine line between when sprinklers or a gaseous extinguishing system should be provided below the operating floor. It depends on the clearance, obstructions, accessibility and continuity of combustibles. 

Fine water spray systems may be potentially superior to CO9 apphcations and may replace halon environments such as telephone central offices and computer rooms. In the fine spray dehveiy system, water is delivered at relatively high pressure (above 100 psi [0.689 MPa]) or by air atomization to generate droplets significantly smaUer than those generated by sprinklers. Water flow from a fine spray nozzle potentially extinguishes the fire faster than a sprinkler because the droplets are smaUer and vaporize more quickly. Preliminaiy information indicates that the smaller the droplet size, the lower the water flow requirements and the less chance of water damage. 

If a sprinkler system is installed in a computer room or similar area, provisions must be made to automatically de-energize all electrical power to the room and equipment, except power to lighting, in the event of sprinkler operation. Ensure that de-energizing activity leads to a fail-safe condition. Preferably, this should take place prior to water application to minimize damage to exposed electronic circuits. This can be accomplished automatically by smoke detection systems. Manual activation is tolerable for constantly attended locations. Where automatic sprinklers are installed in areas containing minimal combustibles as described above, a sprinkler density of 0.10 gpm/ft (0.38 Ipm/m ) should be provided. Refer to NPEA 75. 

Are security personnel trained in sprinkler system operation and cutoff In fire extinguisher use Are computer operating and records rooms, laboratories, and other sensitive areas secured by modem personnel identification systems (card access, hand print, eye retina) ... 

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