Fire break for duct - has two banks of fire resistant pivoting louvres with air gap between housing actuating linkage

摘要

The fire break comprises two parallel banks of louvres (3,3') formed from fire-resistant material and carried on metallic backplates. These backplates pivot about an axis (9) and are actuated simultaneously by a central linkage (5,6) in turn operated by a fusible link. - The louvres are fixed to the backplates off centre so that their lower edges seal on the top edges of the adjacent backplates. For fire dampers intumescent seals (8) are fitted.