Basic Documentation

Table Of Contents
Laboratory Ventilation Codes and Standards
Siemens Industry, Inc. 74
Term Definition Commentary
Containment
Levels and
Ventilation
Requirements:
Canada
(Continued)
21. Airflow control devices and duct sensors located downstream of the exhaust
HEPA filter and upstream of the supply bubble tight backdraft damper or
HEPA filter, or if located upstream, duct penetrations to be sealed in
accordance with:
22. Bubble tight backdraft dampers and HEPA filters to be located in close
proximity to the containment perimeter.
Although the phraseology regarding the
location of duct penetrations that need to be
sealed is rather ambiguous, it would seem to
be good practice to seal all control device
duct penetrations as well as duct
penetrations made for any other purpose.