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Venting data for Enclosure Only <br />There was no PRV installed for pressure relief so the Total Enclosure Leakage measured was extrapolated to the <br />reference pressure of 125 Pa and used in further calculations as the only available leakage for peak pressure <br />relief. <br />In the case where the leakage area of the PRV only was to be used for pressure relief, but leakage area for <br />enclosure and vent was entered as the venting area dataset, to determine leakage area for pressure relief by <br />PRV alone, the leakage of the enclosure would have been subtracted from the leakage of the venting dataset. <br />In the case where the leakage area of the enclosure and PRV was to be used for pressure relief, but leakage area <br />for vent only was entered as the venting area dataset, to determine leakage area for pressure relief by the <br />enclosure and PRV, the leakage of the enclosure would have been added to the leakage of the venting dataset. <br />Positive direction data <br />The positive free vent area provided by the Enclosure Only is 334 sq in, for the enclosure set up in its Positive <br />Discharge Period Condition, with all dampers or installed PRV fixed in the position they would assume under <br />+125 Pa. <br />The leakage of the Enclosure Only in the positive direction was obtained by measuring, and this leakage was <br />manipulated as necessary to determine the leakage area of the Enclosure Only required for positive pressure <br />relief. <br />Negative direction data <br />Peak negative pressure will not form with agent Nitrogen [IG-100]. <br />Peak Pressure data <br />Peak pressure was calculated using the leakage of the Enclosure Only and equations from the Fire Suppression <br />Systems Association (FSSA) "Pressure Relief Vent Guide". FSSA equations depend on experimentally derived <br />curves for peak pressure based on a Leak to Volume ratio for the enclosure. <br />Peak negative pressure will not form with agent Nitrogen [IG-100]. <br />Design details <br />Enclosure pressure limit, [Pa]: 1,000 <br />Discharge time, [s]: 60 <br />Pressure relief vent type: no pressure relief vent (PRV) <br />Peak Pressure relief using: Enclosure Only <br />Peak Positive Pressure <br />Peak positive pressure, [Pa] <br />589 <br />Leak to volume ratio, LVRpoS [sq in/cu <br />ft] <br />62.8 <br />Venting summary — Positive Direction <br />Minimum required leakage, [sq in] <br />206 <br />Venting area used, [sq in], (describes <br />Enclosure Only) <br />334 <br />Additional PRV area needed, [sq in] <br />0 <br />Page 9 of 12 <br />