7
Field-Installed Trim* for Hard/Gypsum Ceilings (cont’d)
3. Dry fit factory-supplied field-installed trim and while in position, mark proper fastening locations
and drill 1/8” hole into AstroHood
™
housing (see Fig. 09).
a. It is of utmost importance to locate holes using the trim as a template to align with the swirl-
weld locations.
b. Failure to do so can create penetrations in the pressure boundary and cause bypass leakage,
compromising the integrity of the filtration system and cleanroom.
4. Remove the trim and apply a continuous, small bead (~ ¼” diameter) of RTV (Dow Corning 732 or
GE 102 recommended) to the ceiling mating surface of the trim.
5. Reinsert the trim, align the holes, and secure in place using blind, closed rivets
(see Fig. 10 & Fig. 11).
a. It is important to use closed end or blind rivets.
b. Otherwise, dirty air may travel along the rivet shaft and into the cleanroom.
6. Remove excess RTV.
Fig. 10 Field-Installed Trim 3
Fig. 11 Field-Installed Trim 4
* Trim is not designed to support ceiling.
** 1-1/2" Field-Installed Trim option is necessary
for units supplied with the 2" foil-backed
insulation option to accommodate insulation
material.
Fig. 09 Field-Installed Trim 2
