Calibration & Repair

Clean Agent 2001 Software

Downloads

Enclosure Integrity Training

Technical Support

Locate a Tester

Testing Enclosures : Sealing Rooms for Clean Agents

This bulletin has been prepared to assist anyone who must seal a room for a Clean Agent
system. Obviously, if a Clean Agent concentration test is to be run, the room will need to
be tight to pass that test. Even so, if no concentration test is required, the room will still
need to be sealed. It is the nature of Clean Agent that it will suppress all flame and fire
spread but it cannot in every instance extinguish the initial source of ignition (for instance,
severe electrical short circuit). Therefore it is critical that the Clean Agent remain in the
protected area until emergency personnel have a chance to deal with a possible continuing
source of ignition.

1. ALL DOORS leading from the Clean Agent protected areas or into another Clean Agent
   zone shall have drop seals on the bottoms, weather stripping around the jams,
   latching mechanisms and door closer hardware. In addition, double doors shall have a
   weather stripped astragal to prevent leakage between doors and a coordinator to
   assure proper sequence of closure. In general, doors shall be treated as though they
   are being weatherproofed for outside use with the least amount of light possible
   passing around all sides. Doors, which for any reason cannot be kept normally closed,
   should be equipped with electromagnets designed to release on alarm.
2. ALL DUCT WORK leading from or into a protected area may be permanently sealed
   off, air tight, with metal plates caulked and screwed in place. Ductwork left in
   service from the building air handling unit must have butterfly blade type dampers
   installed with neoprene seals. Dampers must be spring loaded or motor operated to
   provide 100% air shut-off. It is further recommended that the building air handling
   units be shut down to prevent the spread of smoke or Clean Agent into other areas of
   the building.
3. SELF-CONTAINED AIR HANDLING UNITS within the protected zone may be left in
   service at the owner's option. However, one must consider the possibility that the air
   handling unit could be the source of the fire. Systems not manned 24 hours a day
   should be tied-in to shutdown.
4. PROTECTED AREAS should be enclosed with wall partitions which extend slab-to-slab.
   In areas where this is not possible, the ceiling tiles should be clipped. If the ceiling
   rests on top of the walls, all tiles should be clipped and a caulk be applied around the
   entire perimeter where tile touched the walls. In either case, all tiles should be
   clipped in place within 4 feet of any discharge nozzle.
5. ANY HOLES, CRACKS, OR PENETRATION leading into or out of the protected area must
   be sealed. This includes pipe chases and wire troughs.
   All walls should be caulked around the inside perimeter of the room where the walls
   rest on the floor slab and where the walls intersect with the ceiling slab above.
6. IF A RAISED FLOOR continues out of the Clean Agent protected area into adjoining
   rooms, bulkheads must be installed under the floor, directly under above-floor border
   partitions. These bulkheads must be caulked top and bottom.
   If the adjoining rooms share the same under-floor air handlers, then the bulkheads
   must have dampers installed the same as required for ductwork. See Item #2.
7. ALL FLOOR DRAINS should have traps and the traps should be designed to have water
   in them at all times.
8. POROUS BLOCK WALLS must be sealed slab-to-slab to prevent gas from passing
   through the block. Two or three coats of paint are normally required. Unpainted
   block walls are totally unacceptable.
9. IN GENERAL, the basic intent is to make Clean Agent protected areas as air tight as
   possible during and after Clean Agent discharge. Clean Agent is heavier than air and
   therefore, openings below floors are usually more critical than those above a ceiling.
   However, during discharge the room does get pressurized to some extent and any gas
   that can be pushed out of the room will not return. Smaller rooms are much harder
   to seal then large rooms because each little crack becomes much more significant as
   the surface area to volume ratio changes.
10. ONCE THE GAS IS DISCHARGED, in most jurisdictions, it must remain in the room at
    it’s designed concentration at least ten minutes. The length of time the agent will
    remain is directly proportional to the “air tightness” of the room..

The above 10 points are not all inclusive nor guarantee that the concentration test will pass.
They are, however, presented as the most common items which affect Clean Agent
concentration tests. If, in addition to presenting a few specific areas of concern, they
provoke thought about the overall "air tightness" of the enclosure, then they will have served
a good purpose.

Specialized air sealing materials

Hire contractors who are familiar with airsealing, not unspecialized contractors.