GB2191099A - Hood for use in fire protection, in emergency or evacuation - Google Patents

Abstract

A smoke hood, particularly for wearing on the head in a fire protection situation, includes a hood portion 12, 14 of heat resistant sheet or film material. At least a part of this is transparent. The hood also includes neck closure means 20, 30 whereby an open end of the hood can be closed around the neck of the wearer. The hood portion has a filter compartment 22 which encircles the hood. Such a compartment is defined by a pair of walls one of which may be the hood material. The filter compartment has an inlet 26 from the exterior and an exit 28 to the interior of the hood, preferably being diametrically opposite each other. <IMAGE>

Description

SPECIFICATION Hood for use in fire protection, in emergency or evacuation This invention relates to a hood which may be worn on the head in fire protection situations orwhen a person is to be evacuated from a room or an aeroplane where there is a fire orwhere there is danger of suffocation.

Many kinds of protective hoods and respiratory devices have been disclosed. These are often intended to enable the wearer to breathe in the situations outlined above. Examples of these are asfollows: British Patent 1587121 (Head gearand respirator for air crew) British Patent 1593360 (Hood of plastics material having special arrangement ofwelded seams) British Patent 1352982 (Stretchable hood) PCTApplication International Publication No. WO 82/02665 (Smoke hood) August 1982.

One particular importantfeature of smoke hoods for use in emergency situations is that hood should have sufficient filter medium to provide reasonable quality of breathable gas in the interior of the hood and yetthe design of the compartment containing thefiltermedium must be such thatthe opportunity ofgasto by-pass the filter medium is minimised.The conventional arrangement of a filter pad located over the nose or mouth of the wearer (e.g. US Patent 4231118) has frequently been found ineffective in meeting this need.

According to the present invention, a smoke hood includes a hood portion of heat-resistant sheet orfilter material at least a part of'which is transparent, and neck closure meanswherebyan open end ofthe hood can be closed aroundtheneckofthewearer when the hood is being worn,the hood portion having a filter compartment which encircles the hood, preferably substantially at mouth or nose level when the hood isworn,the compartment being defined by onewall formed by the material ofthe hood and a second wall arranged adjacent thereto, the compart ment having an inlet connecting it to the exterior of the hood and, preferably substantially diametrically opposite, an exit to the interior ofthe hood.

The filter compartment may contain both means for removing particles such as smoke particles from any gas passing through the compartmentand means for removing certain gases from the gas passing through. The compartment preferably contains a powerful gas filtering agent such as carbon cloth or afibre material carrying or impregnated with activated carbon.

In a preferred embodiment of the invention, the walls ofthe compartment are welded together by intermittent or scattered spot welds in order to ensure that any gas travelling between inlet and exit ofthe compartment follows a tortuous path through and/or pastthefiltering agent.

The said second wall may be made of the same material as the hood. Forexamplethese parts may be made of the synthetic plastics heat resistant film known by the Trade name MYLAR. The neck closure means may be formed by two loops of tape or cord located in a peripherai tube defined by folding over a marginal portion ofthe open end ofthe hood portion.

Furtherfeatures of the invention will become apparentfrom thefollowing description of an illust- rativeembodiment, given with referencetotheac- companying drawings and without intention of limitation, since equivalent specific designs can employ the principle of the present invention.

In the drawings: Figure lisa diagrammaticfront elevation of one example of smoke hood in accordance with the invention; Figure2 is a cross-section on the line Il-Il through the hood shown in Figure 1; Figure 3 is a rearview of the hood shown in Figure 1; Figure4is a diagrammatic plan showing the neck closure means.

The illustrated hood 10 has a hood portion defined a front sheet 12 and a rear sheet 14 of heat resistant synthetic plastics material, for example "Mylar".The illustrated hood also includes a neck closure means 16which is essentially made up of a loop oftapeor cord 18 and a second loop of tape or cord 20. The neck closure means will be described in more detail later, in connection with Figure 4.

The hood portion has a filter compartment 22 which encircles the hood. As seen in Figures 1 and 3, the filter compartment is located substantially at mouth or nose level when the hood is being worn by a wearer. As best seen in Figure 2, the peripherally outerwall ofthis filter compartmeiit is constituted by portions of the sheets 12and 14and the peripherally innerwall ofthis compartment is constituted byan encircling sheet 24 of heat resistant plastics material, which may be the same mylarfilm.

In an alternative embodiment of the invention, the peripherallyinnerwall of the filter compartment could be constituted by the sheet material of the hood portion andthe peripherally outerwall could be an encircling strip of material. The strip, in either case, is welded (or adhesively seamed, but welding is currently preferred) to the walls 12 and 14so defining a closed ortubular peripherally encircling filter compartment. This contains a filter medium which encircles the hood.

As seen best in Figures 1 and 2, holes 26 are provided in thewall 12to constitute an inlettothefilter compartment 22. Holes 28, see Figures 2 and 3, are providsed in a partofthewall 24 which is diametrically opposite to the holes 26 when the hood is in its normal worn position. These holes 28 consitute exits for filtered gas from the filter compartment to the space within the hood, it being readily seen that this arrangement ensures that any gas entering the hood according to the invention via the inlets 26 passes either clockwise or anti-clockwise around the filter compartment and leaves the filter compartment, entering the interior of the hood, via the holes 28. This arrangement ensures that any gas which reaches the interior of the hood has been thoroughly exposed to thefiltermedium.

The neck closure means 16 hastwo loops 18,20 which are seen best in the plan view of Figure 4. One partof each loop is located within an encircling tubular space 30, Figure 2, provided by folding over a marginal portion of the sheet material 12, 14 adjacentto the open end of the hood. A part of each loop extends outwardly laterally from the hood and by pulling these free portions ofthetwo loops the neck portion ofthe hood can be closed onto the neckto any desired extent. The particularform of neck closure forms no part of the novelty ofthe present invention, and it will be appreciated that other neck closure arrangements may be employed.

According to a preferred embodiment of the invention, a numberof scattered through welds (not shown) may be made joining the wall of 24 with the walls 12 and 14atspaced regions. The purpose of this is to hold the opposed walls ofthe filter compart- menttogether at spaced locations, with thefilter medium trapped there between, in order to ensure thatthere is a tortuous path forthe gases from the inlet holes 26 to the outlet holes 28. Reference has been made to spot welds but it will be understood that short bar welds are equally suitable. Naturally such spot or barwelds will be located sufficientlyfar apart fro each otherthatthe resistance to gas flow due to the tortuousness ofthe path is not made unacceptably high.

Claims (8)

1. A smoke hood including a hood portion of heat-resistantsheetorfilm material at least a part of which is transparent, and neck closure means whereby an open end of the hood can be closed around the neck ofthewearerwhen the hood is being worn,the hood portion having afiltercom partmentwhich encircles the hood (preferably sub- stantially at mouth or nose level when the hood is worn), the compartment being defined by one wall formed by the material ofthe hood and a second wall arranged adjacentthereto, the compartment having an inlet connecting it to the exteriorofthe hood and, preferably substantially diametrically opposite, an exit to the interior of the hood.

2. A hood according to claim 1 inwhichthefilter compartment contains both means for removing particles such as smoke particles from any gas passing through the compartment and means for removing certain gases from the gas passing through.

3. A hood according to claim 2 in which the compartment contains a gas filtering agent such as carbon cloth or a fibre material carrying or impregnatedwith activated carbon.

4. A hood according to claim 1,2 or3 in which the walls ofthe compartment are welded together by intermittentorscattered spot welds in ordertoensure that any gas travelling between inlet and exitofthe compartment follows a tortuous path through and/or pastthefiltering agent.

5. A hood according to any preceding claim in which the said second wall is made of the same material as the hood.

6. A hood according to any preceding claim in which the neck closure means is formed by two loops oftape or cord located in a peripheral tube defined byfolding over a marginal portion oftheopen end ofthe hood portion.

7. A smoke hood substantially as herein described with reference to and as illustrated in the accompanying drawings.

8. Any novel combination or sub-combination disclosed and or illustrated herein.