Seals
Edges of a fire door usually need to have fire rated seals which can be composed of:
An intumescent strip, which expands when exposed to heat
Gaskets to prevent the passage of smoke
Neoprene weatherstripping
When intumescent seals are used in the door design, use of the correct seal is crucial in the fire rating performance the door assembly. Seals may vary in chemical composition, expansion rate, expansion volume, and/or charring characteristics.
