| 摘要 |
A fire retardant transom or fire retardant mullion 80 for a door or window frame includes two elongate members 86, 88 having transversally projecting portions 82. It further includes an impeding feature, preferably a hole 84, acting as a thermal break between the elongate members. The projecting portions are arranged to form a channel for receiving intumescent material 46, 72, 76, 90 from either or both of the impeding feature and the portion of the door corresponding to the transom or mullion. The arrangement is such that the intumescent material is abutted by the projecting portions so that opening, bowing or dishing of the door or window is resisted. |
