Room Integrity Testing Services
Under International Standard No 14520 it is a requirement that a room Integrity Test is carried out at the time of the fire suppression installation. It is also a recommendation that a room Integrity Test is carried out on an annual basis as part of the routine maintenance schedule. This test is designed to ensure that an extinguishing concentration is held for a sufficient time (normally 10 minutes) to prevent re-ignition in the event of a fire.
Studies reveal that the predominant cause of failure of gaseous extinguishing systems is inadequate room sealing. It is also found that room integrity performance reduces with time, usually due to changes in construction, cabling or services.
It is important to ensure that good room integrity is established and maintained within the data centre space, particularly bearing in mind the potential consequences of system failure. Annual integrity inspection and testing are also required by the BFPSA and are routine practice at most major commercial institutions. The benefits of ensuring room integrity are widely recognised by insurers and regulatory authorities, who frequently require such testing.
Fire Suppression Integrity Test Overview
‘Door fan’ Integrity Testing methodology provides a means of predicting the retention time without the need to release the extinguishing gas. The door fan test methodology is in accordance with the general requirements specified in BS 5306, BS:ISO 14520, NFPA 12A, NFPA 2001 and the BFPSA Code of Practice for Gaseous Extinguishing Systems.
Door Fan Test
Small pressure differentials between the enclosure and surrounding areas are achieved by positioning the fan equipment in the data centre doorway. Pressure and airflow measurements are taken, from which the leakage characteristics of the enclosure are established. The predicted retention time is calculated from these leakage characteristics and the enclosure and extinguishing system data.
Room Integrity Test
- The enclosure is measured, a plan made and the type and quantity of extinguishant recorded. The height of the highest hazard in the enclosure (risk height) is noted.
- Where relevant, doors within the enclosure are opened and several false floor and ceiling tiles are removed so that the protected enclosure is tested as one space. A return air path is established outside the enclosure by opening doors/windows as appropriate.
- The door fan equipment is set up in a suitable door opening. Personnel may continue to work within the enclosure during the test and may enter and leave, subject to access, except when pressure readings are being taken.
- Any air handling equipment involving supply into, or extract from, the enclosure will need to be set by the client or end-user into the same condition as would occur on system discharge (usually dampers closed and fans off). This need occurs only whilst pressure readings are taken. Recirculation and a/c units without fresh air make-up may be left operating throughout the test to prevent temperature build-up in the enclosure. Details of the arrangements are noted
- The extinguishing system and enclosure data obtained earlier is entered on to the computer. This calculates the design concentration and the column pressure (typically between 4 and 20Pa) that would be exerted by the gas after discharge.
- The door fan(s) is used to pressurise and depressurise the enclosure to the column pressure and the fan pressure required in each case is recorded. For certain system design a series of pressure readings are taken.
- The pressure data is entered on to the computer which calculates the airflow, equivalent leakage area and the retention time.
- If the result satisfies the specified retention time (usually 10 minutes) the enclosure is deemed to have passed the test.
- If the retention time is less than that required, a detailed inspection is undertaken to establish the main leakage paths. This includes floor and ceiling voids as relevant.
- On occasions, chemical smoke pencils may be used in conjunction with the door fan equipment to assist leakage identification. These produce only very small quantities of smoke at the perimeter of the enclosure and are not used in the vicinity of any sensitive electronic equipment.
- Should the leakage path distribution be found to be other than the worst-case situation assumed in the initial computer calculation, the retention time is recalculated accordingly. Also, if practicable, major leaks may be temporarily sealed, new pressure readings taken and a revised retention time calculated. Retention times meeting requirements are recorded as passes, subject to any necessary corrective actions; those not doing so are reported to have failed.
- A written test report will be submitted. The report contains details of the enclosure, extinguishing system parameters, pressurisation results and predicted retention time graph. Recommendations are given advising the sponsor of any leakage areas or other features requiring remedial action.
Note – The duration of the test is approximately two hours per enclosure.