Ruskin® has more than 70 models that can be used with the UL I503 design specification, including the high-performance, low-profile FSD–LP series and DFD-LP

Grandview, MO – (Jan. 26, 2017) –The Ruskin® portfolio of life safety solutions includes more than 70 models of 1½-hour rated fire and combination fire/smoke dampers that can be mounted horizontally in UL design I503. The I503 design is a two-hour fire-rated protective membrane made from steel studs and gypsum board. Until recently, UL555 fire dampers were only to be applied in concrete/masonry construction for horizontal applications.

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life safety dampers available for UL Design I503 horizontal installations
The high-performance DFD-LP is the newest Ruskin®dynamic rated fire damper that can be used in design I503.