Basic Documentation

Ventilation Systems
Siemens Industry, Inc. 125
Topic Requirement(s) Commentary
Periodic
Inspection
and Testing
- Canada
(Continued)
• Containment Level 4 Additional Room Integrity Testing:
Integrity of containment to be tested by pressure decay testing. Acceptance criteria:
two consecutive tests with a minimum of 250 Pa (1 in. w.g.) loss of pressure from
an initial 500 Pa (2 in. w.g.) over a 20 minute period.
This test is not a mandatory requirement for recertification if no modification or
changes have been made that will affect the integrity of the laboratory, and if a
visual inspection of the containment barrier membrane indicates that the integrity
has not been compromised; if the perimeter integrity is suspect upon visual
inspection, the requirement for repeating the pressure decay test should be
determined in consultation with the laboratory supervisor, Biological Safety
Officer/Institutional Biosafety Committee.
5.2.2 Room Pressure Decay Testing
The basic procedure for room pressure decay testing under negative pressure is as
follows:
• Isolate the area by closing and securing all doors, valves and bubble tight dampers
at the containment barrier (avoid temporary sealing measures in doors, windows
and services that would cover permanent seals and not permit their testing for
leakage); plug all pressure sensor lines, e.g., magnehelic gauges.
• Install a calibrated inclined manometer across the containment barrier such that it
is not affected by air distribution. Manometer to have minimum accuracy of 10 Pa
(0.05 in. w.g.) and capable of reading pressure up to 750 Pa (3 in. w.g.).
• Install a ball valve in the piping between the vacuum pump/fan and the room to
allow the room to be sealed once the test pressure has been attained.
• Connect a vacuum source to the room and create a 500 Pa (2 in. w.g.) negative
pressure differential; allow room to stabilize and close the valve between the
vacuum pump/fan and the room to seal room at 500 Pa (2 in. w.g.).
• Dynamically trend pressure loss starting at 500 Pa (2 in. w.g.) negative pressure
differential; record the differential pressure at 1 minute intervals for 20 minutes.
• If repeat test is required, allow 20 minute wait period.
• Disconnect the vacuum pump/fan and open the ball valve slowly to allow room
pressure to return to normal condition.
• If leak rate exceeds the acceptance value:
• pressurize the room to a pressure adequate to locate leaks;
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