Pottorff Company Model SMT-CRD ceiling damper in combination with the noted Delta Electronics fan assemblies, is approved for use in fire-resistance rated floor-ceiling or roof-ceiling assemblies not exceeding a 3-hr fire-resistance rating for non-combustible construction, or not exceeding a 1-hr fire-resistance rating for the combustible assemblies listed below, as an alternative to sheet metal dampers. The maximum number of ceiling dampers in an assembly is based on the approved number of sheet metal dampers in the specified design.
Model SMT-CRD ceiling damper has been approved for use with the following ventilation fans:
Delta Electronics, Inc.
| Delta BreezSmart |
SMT130, SMT130H, SMT130M, SMT150, SMT150D, SMT150LED |
| Delta BreezSlim: |
SLM80, SLM100 |
Model SMT-CRD ceiling damper has been approved for installation in floor/ceiling and roof/ceiling assemblies previously rated with a hinged-door sheet metal damper installed in the ceiling and for use with the following 1-hr fire-resistance rated combustible construction floor-ceiling and roof-ceiling assembly designs:
- L521
- L546
- L558
- L562
- L574
- L576
- L581
- L583
- L585
- P522
- P533
- P538
- P545
Ventilation fans shall be ducted out of the plenum space using any UL 181 Class 0 or Class 1 duct.
