GB2198775A

GB2198775A - Fire resistant door leaf with intumescent surround seal

Info

Publication number: GB2198775A
Application number: GB08630463A
Authority: GB
Inventors: David Sidney Clarke Smith
Original assignee: Imperial Chemical Industries Ltd
Current assignee: Imperial Chemical Industries Ltd
Priority date: 1986-12-19
Filing date: 1986-12-19
Publication date: 1988-06-22
Anticipated expiration: 2006-12-19
Also published as: GB2198775B; GB8630463D0

Abstract

The invention provides a fire resistant door leaf which is less likely to become contaminated in medical, pharmaceutical and other laboratory situations than known constructions. The leaf comprises a rigid, heat resistant panel faced on both sides with metal sheets (3, 4) which extend beyond the edges of the panel and which are bent back to define channel portions (5, 6) surrounding the panel and spaced to form a recess (7) around the door leaf. Intumescent sealing material (8) is disposed in this recess, and this may be covered by a facing material (9) to provide a smooth surface with fewer sites for bacterial lodgement. <IMAGE>

Description

FIRE RESISTANT DOOR lAAF This invention relates to fire resistant door Fire resistant door leafs made from rigid heat resistant panels are known. However, their surfaces tend to become contaminated, for example with microorganisms and they are thus unsuitable for use in certain premises used for medical or pharmaceutical purposes or for example in premises used for certain types of research.

This invention comprises fire door leafs which comprise a rigid, heat resistant panel faced on both sides with metal sheets which extend beyond the edges of the panel and which are bent back towards the panel at their outer edges to define channel portions surrounding the panel, the channel portions of the sheets being spaced apart to form a recess surrounding the door leaf and intumescent sealing material located in the said recess.

Suitably the panel is framed round its edges with metal U channels before application of the facing sheets, thus allowing welding of the facing sheets to the U channels at the inner parts of the recess.

Suitably the intumescent sealing material is faced with a combustion resistant covering (for example a polyvinylchloride plastic strip or sheath or a combustion resistant filler) in order to improve the cleanliness of the door further.

A door of the above construction may be closed by a latch or preferably a conventional door closure device in the absence of a latch if it is desired to avoid further possible sites for bacterial lodgement.

Doors of the above type may be made as double or single doors.

In the former case, expansion of the intumescent seals between the two doors create a seal between them in the event of a fire.

One form of the invention will now be described with reference to the drawings, of which Figure 1 shows an elevation of a rigid heat resistant panel, framed with metal U channels 2. Figure 2 shows a cross section through an assembled door leaf, in which metal facing sheets 3 and 4 are formed with edges bent backwards towards the edges of panel 1 to define channel portions 5 and 6 which surround the panel and which are spaced apart to define a recess 7 which surrounds the door leaf. intumescent sealing material 8 is located in recess 7 and is faced with a polyvinylchloride layer 9. The inner edges of channel portions 5 and 6 are welded to U channels 2.

The door may be a plain leaf or may be provided with a window, suitably triple glazed with at least one, preferably the middle, pane being heat resistant glass and the outer panes being preferably flush with the door faces. It may be provided with a latch or preferably with no latch but being urged into the closed position with a door closure device which is suitably located on the side of the door on which any loss of cleanliness may be most readily tolerated.

The metal sheet is suitably zinc coated mild steel sheet.

Conventional hinges may be employed at the swinging edge of the door, and at the hinges the intumescent seal may be omitted as the hinges themselves provide a satisfactory fire barrier.

When a fire occurs with the door leaf in the closed position the intumescent seal expands sealing the gaps between the door and the door frame and (in case of a double door) between the doors, thus providing a barrier.

Claims

CLAIMS:

1. A fire door leaf, comprising a rigid, heat resistant panel faced on both sides with metal sheets which extend beyond the edges of the panel and which are bent back towards the panel at their outer edges to define channel portions surrounding the panel, the channel portions of the sheets being spaced apart to form a recess surrounding the door leaf, and intumescent sealing material located in said recess.

2. A fire door leaf as claimed in Claim 1, wherein the edges of said panel are framed with U-section metal channels, and the free edges of the channel portions of the sheets are welded to these channels at the inner parts of said recess.

3. A fire door leaf as claimed in Claim 1 or Claim 2, wherein a combustion resistant facing is disposed over the intumescent sealing material.

4. A fire door leaf substantially as hereinbefore described with reference to Figs. 1 and 2 of the accompanying drawings.