The more effectively sealed a room is, the more likely it is to pass the integrity test. In some cases, however, effective sealing gives rise to another potentially harmful condition that requires corrective action to prevent excessive pressure build-up. When high volume extinguishing agents are used, large volumes of air are displaced, giving rise to pressure spikes which must be counteracted using pressure relief vents to ensure structural stability. Pressure relief is often required for enclosures housing non-inert systems as the level of sealing required to avoid leakage is very high, and they are particularly prone to high pressure spikes.
Pressure Test installs specialist pressure relief vents which allow the safe displacement of air. These vents remain closed under normal circumstance, allowing no back-flow of air from outside the protected area. When extinguishing agent is released the vent opens to relieve excess pressure, then it closes again to maintain room integrity.