APPARATUS FOR CLOSING OFF AN UNDERGROUND PASSAGE

Abstract: The invention relates to apparatus (1) for closing off a space or an area, in the embodiment a passage comprising a device (3) adapted for mounting in the passage (2) and to be deployed against a boundary wall (4) of the passage whilst providing through access for users of the passage (2). In the embodiment the passage (2) is a tunnel of generally circular section. The device (3) is in the form of a gas-impermeable bag or flexible container of fire-resistant material that is housed in a protective housing (5) as by folding. The housing (5) is mounted on the wall (4) of the tunnel (2) at the roof or an upper or overhead (as viewed) (Fig. 1) part and also houses, in addition to the bag (4), a source of pressurised fluid such as a gas which can be air, nitrogen or other suitable gas, and an inflation mechanism (6) for connecting the bag with the source. The bag (3) comprises a toroidal structure with the central circular area (7) in the embodiment holding a flap or cover arrangement (8) whereby the device (3) is adapted to allow passage of personnel (users of the passage) from one side of the deployed device (3) to the other, along the passage (2).

Description: APPARATUS FOR CLOSING OFF AN UNDERGROUND PASSAGE The invention relates to apparatus for closing off a passage. The passage may typically be an underground tunnel or shaft, typically produced by man operated tunnel boring machinery. Such boring operations have significant Health and Safety implications. Thus tunnels and access shafts are usually confined spaces having potential risks associated with for example access and egress, poor ventilation, leading to toxic and flammable gas production, large machinery occupying a significant proportion of the tunnel and access shafts associated with drilling activities at the tunnel face, removal of spoil and installation of the tunnel sections, and accidental exposure to explosions, fire, smoke and fumes. Indeed, the dangers from explosions, fire, smoke and fumes caused by electrical equipment are a serious risk, especially in longer tunnel bores where access to and from the exit shafts is attenuated. It has therefore been the practice hitherto to include rigid fire doors at pre-set intervals along the length of the tunnel. In the event of a fire or explosion these doors can be manually closed, where machinery position allows, to limit the effects of the fire and the passage of toxic combustion products along the tunnel. These fire doors have disadvantages, for example they can restrict movement within the tunnel and can lead to a crush hazard with spoil removal operations on trucks or conveyor belt, they often become damaged and they are difficult to deploy in an emergency, and they are difficult and time consuming to move as the tunnel proceeds. It is accordingly an object of the invention to seek to mitigate these disadvantages. According to a first aspect of the invention there is provided apparatus for closing off space, comprising a device adapted to be deployable against a boundary wall of the space for isolating a part of the space, from another part thereof. The container or containers supplying the gas for inflation may be mounted within or external to the housing. The inflation mechanism can be controlled automatically or manually. Apparatus for closing off a space is hereinafter described, by way of example, with reference to the accompanying drawings. Fig. 1 is a schematic cross-section of a space in the form of a passage including apparatus according to the invention in an undeployed condition; Fig. 2 is an elevational view from one side of the apparatus of Fig. 1 , in a deployed condition; and Fig. 3 is a transverse sectional view of the apparatus of Fig.2. Referring to the drawings, there is shown apparatus 1 for closing off a space or an area, in the embodiment a passage comprising a device 3 adapted for mounting in the passage 2 and to be deployed against a boundary wall 4 of the passage for isolating a part of the passage from another part thereof whilst providing in the embodiment shown, through access for users of the passage 2. In the embodiment the passage 2 is a tunnel of generally circular section. The device 3 is in the form of a gas-impermeable bag or flexible container of fire-resistant material that is housed in a protective housing 5 as by folding. The housing 5 is mounted on the wall 4 of the tunnel 2 at the roof or an upper or overhead (as viewed) (Fig. 1 ) part and also houses, in addition to the bag 4, a source of pressurised fluid such as a gas which can be air, nitrogen or other suitable gas, and an inflation mechanism 6 for connecting the bag with the source. The bag 3 comprises a toroidal structure with the central circular area 7 in the embodiment holding a flap or cover arrangement 8 whereby the device 3 is adapted to allow passage of personnel (users of the passage) from one side of the deployed device 3 to the other, along the passage 2. The housing 4 itself has a cover or closure which is operated on inflation of the device by a mechanism 9 which can be manual or automatic. An automatic mechanism 9 can be operated by temperature or smoke. In use, when the mechanism 9 is actuated, inflation of the bag is initiated by mechanism 6, the protective housing 5 opens and the toroidal gas bag 3 is deployed, as shown in Figs. 2 and 3. The inflated device 3 thus has a toroidal configuration with an external inflated wall sealing firmly at 10 against the tunnel wall 4 and services (e.g. pipework) . The flap mechanism 8 is in the form of a sealable access mechanism flap for passage of personnel through the device 3 and along the tunnel and is also deployed on inflation of the device. When deployed, the device seals off the space so that fire, fumes etc. are contained whilst allowing personnel to evacuate the space. In the embodiment described herein with reference to the drawings, the space is shown as a passage or tunnel, though it could be any generally enclosed space in which one area may be required to be isolated from another, such as an underground or subway platform, a tunnel for an underground, metro or subway train, passenger or personnel access tunnels or passages at underground metro or subway stations, passages or tunnels in public buildings, the fuselage of an aircraft, companionways or passages in ships, a hold of a ship, a submarine, a lift shaft, a mine shaft, or the like area. Thus in a tunnel or tunnel which is being formed, by a cutting or tunnelling machine which may run on a track, the device may in another embodiment be mobile in that it is mounted on the cutting or tunnelling machine. In particular, the device may be mounted on the rear of the machine, at the end thereof opposite the cutting or boring head. If there is a hazard such as a fire on or near the machine, the device is deployed to seal off the part of the tunnel in which the machine currently finds itself, thereby isolating that part from the rest of the tunnel, whilst enabling personnel operating the machine to escape from that part through the deployed device. Alternatively, or in addition, there may be a plurality of devices embodying the invention spaced apart at intervals along the length of the tunnel, whereby to enable areas in the form of sections of the tunnel to be isolated, in, say, an emergency. The gas used to inflate and thus deploy the device may be carbon dioxide, nitrogen, or other inert or non-flammable gas. The housing 5 as shown in the drawings may essentially comprise a closure or lid which is operable as by swinging open or dropping off to allow deployment of the bag. In a development, the housing may have a closure in the form of a roller-shutter device which on actuation by the device 9 opens to allow deploying of the bag, there being a return means such as a tension spring which returns the closure after deployment of the bag so that the closure is not an obstruction to passage of people from one side of the device to the other. The deployed device may, it will be understood, prevent "flash " , and the material from which the bag is made is suitably gas-impermeable, so as to retain the gas, and fire resistant, to assist in prevention of spread of fire from one side of the device to the other and may be made of a material such as Kevlar (Registered Trade Mark) which is virtually unpuncturable. Alternatively, where the material could be punctured, it can be of the kind which is self-sealing whereby to prevent escape of gas. The flap mechanism 8 is also capable of being modified. Thus there may be two pairs of flaps, one flap of each pair being at a respective side of the device when deployed, there being a "slit" between the pairs as shown at 8' in Fig. 2, so enabling the flap pairs to be pushed aside to allow through passage of people from one side of the device to the other. Each flap may be weighted by say chains or other weights at the base to ensure that the flaps hang down to ensure that the flaps close off the passage when personnel are not passing through. There could also be a means to contain pressure build-up from one side of the device to the other for example a water container. The apparatus could also include two toroidal devices 3, one behind the other as considered in a direction from one side of the apparatus to the other. The or each bag may be about a metre thick, as considered in the direction from one side of the device to another, and may also be about a metre high. Whatever the dimension, the bag(s) may be deformable as shown in Fig. 3, and also this ability to deform may allow it on deployment to envelop railway lines, cabling, trunking etc. The device may include brushes or "fingers " which may fill in any gaps when the device is deployed. The device may also be capable of containing an explosion. This may be achieved by providing the cross-section of the toroidal bag to be tapered, or of wedge-shape. When deployed the wedge shape is deployed such that the tapered surface is directed upwardly into the wall in the direction from which a blast is likely to come, the force of any blast thus forcing the apparatus firmly against the wall and retaining the device in position, and thus containing the blast. The apparatus could also include a reinforcement or stiffener to strengthen the bag, plus mounting or attachment points for say a scaffolding or a trestle to assist in maintaining a deployed device in the deployed position. There may also be valve(s) or nozzle(s) to allow exchange of gas or top- up gas. The apparatus could include fire extinguishing means such as means to release foam, to help extinguish fire, carried by the device, porting arrangements for lighting, and communication devices mounted thereon, such as a telephone or intercom. The bag could be rough to provide a modified exterior which can provide a frictional grip on the wall when deployed. The apparatus could also be such that people cannot pass through, whilst providing as before limit or restriction of smoke passage from one side of the device to another, without providing a gas-tight seal. The embodiments of the apparatus thus seals an area in use against passage of smoke, fumes and/or fire, thus providing health and safety for, say, tunnel boring equipment, operators and other personnel. It also has the advantage of providing an automatic or manual method of passage, shaft or tunnel closure to control the passage of smoke, fumes and other toxic, flammable or other gases, gas mixtures and gas-carried particulates whilst allowing user access and egress. Thus a device as hereinbefore described with reference to the drawings which device may be considered as a gas inflatable stopper, may therefore suitably comprise: a flexible or expandable bag or container that is inflated to form a seal against a tunnel wall or walls; a protective housing covering the un-inflated bag or container; a mechanism to attach the device to the tunnel wall; a mechanism to deploy the protective housing; a mechanism to control the injection of pressurised gas into the gas bag; a reservoir of pressurised gas or means of external supply of pressurised gas; a device to monitor stored or externally supplied gas pressure; a mechanism to allow the passage of personnel through or round the inflated bag or container whilst controlling the passage of smoke, fumes, etc. There may be a plurality of devices, or containers. The or each bag or container may suitably have dimensions and shape- that allow it to fit closely against the tunnel wall(s) when inflated. Thus, the or each bag or container may have a rectangular or circular or any shaped cross section according to the cross sectional shape of the tunnel into which the apparatus is fitted. The or each bag or container is preferably constructed from flexible, foldable or expandable material, and that material may be, but not limited to, fireproof or fire resistant material. In use, the apparatus is suitably positioned and fixed at any position on the tunnel wall, typically in positions that do not affect access and egress, and other services, when inflated. The source of fluid for inflating the device may comprise air, nitrogen or other suitable gas. The gas for inflation may be provided by a single or plurality of gas containers or by a separate gas supply. The container or containers supplying the gas for inflation may be mounted within or external to the housing. The inflation mechanism can be controlled automatically or manually.

Claims: CLAIMS 1 . Apparatus for closing off a space, comprising a device adapted to be deployable against a boundary wall of the space for isolating a part of the space from another part thereof. 2. Apparatus according to Claim 1 , the device being adapted to be deployable by comprising an inflatable device which is adapted to provide through access for a use of the space. 3. Apparatus according to Claim 2, the device comprising a toroidal device, whereby to provide said through access. 4. Apparatus according to Claim 2 or Claim 3, comprising non- inflatable access means having a boundary defined by the inflatable device. 5. Apparatus according to Claim 4, the access means comprising a flap arrangement. 6. Apparatus according to any preceding claim, comprising a housing for the device adapted to permit deployment thereof. 7. Apparatus according to Claim 6, comprising a source of fluid under pressure for inflating the device. 8. Apparatus according to Claim 6, the source being housed in the housing. 9. Apparatus according to Claim 7 or Claim 8, comprising means automatically to deploy the device. 10. Apparatus according to any of Claims 2 to 9, the device comprising a plurality of compartments. 1 1 . Apparatus according to Claim 10, the device comprising a fire resistant material. 1 2. Apparatus according to Claim 10, the device comprising a "flash " resistant material. 1 3. Apparatus according to Claim 10, the device comprising a gas impermeable material. 14. Apparatus according to any of Claims 6 to 1 2, the housing comprising a closure which is openable to allow deployment of the bag. 1 5. Apparatus according to Claim 1 4, the closure comprising a roller shutter device with a return means adapted to obviate destruction of the space by the closure after deployment of the device. 16. Apparatus according to any of Claims 5 to 1 5, the flap arrangement comprising two pairs of flaps. 17. Apparatus according to Claim 16, the flaps comprising weights to provide that the flaps hang down. 1 8. Apparatus according to any preceding claim, comprising fire extinguishing means. 1 9. Apparatus according to any preceding claim, comprising porting arrangement for lighting and/or communication devices. 20. Apparatus according to any preceding claim, the device comprising a roughened external surface adapted to provide a frictional grip on a wall when deployed. 21 . Apparatus according to any preceding claim, comprising reinforcement of the device. 22. Apparatus according to any preceding claim, comprising means to fill gaps when the device is deployed. 23. Apparatus according to Claim 22, the means comprising brushes. 24. Apparatus according to any preceding claim, the device being wedge shaped when deployed. 25. Apparatus according to Claim 24, the device being deformable when deployed. 26. A space, tunnel, bore, passage or shaft, including apparatus according to any preceding claim.

Inventors: SMITH ALAN JAMES, WATERS COLIN JOHN, SMITH, ALAN, JAMES, WATERS, COLIN, JOHN
Applicants: SMITH ALAN JAMES, THAMES WATER UTILITIES, WATERS COLIN JOHN, SMITH, ALAN, JAMES, THAMES WATER UTILITIES LIMITED, WATERS, COLIN, JOHN
Application year: 1999
Main classification: E21F17
IPC codes: E21F17