Canon PSC 2000 - Manual (Page 34)

2000 Fire Door-Fan Manual updated 2002-05-28
Page 34 of 58
This will only help if there is continual mixing during the retention period. If the air-
handlers are shut off at discharge, more agent will give less retention time.
Rooms with suspended ceilings will double the retention time usually when agent is
discharge above the ceiling for mixing and no mixing cases.
Extended discharges will increase retention time for the duration of the discharge.
Eliminate Static pressure during retention
In cases where this is large, reducing it can increase the time.
Reduce High Static Pressures if present
Have the building HVAC shut down on discharge if possible. Test run the enclosure without the
static pressure to see if it will make enough difference to have it done.
Reduce the Minimum Protected Height
Determine what exactly needs to be protected in the room for the required retention time.
Open up the cabinets to see if they have anything in them or can a lower level be chosen.
Reduce the Minimum Required Retention Time
Base this on the response time of the fire department or local operators who would be trained
to deal with the fire event. See Step 12 in the Guide for help.
Improper training of testing technician
Learning how to operate the software and hardware and analyse room problems is often a huge
factor in passing enclosures and avoiding future problems.