FR2793147A1 - Protective garment for operating in polluted atmosphere comprises supple airtight suit with air feed, mask and valve to evacuate used air - Google Patents

Abstract

The garment consists of a supple airtight suit (1) covering the whole of the wearer and connected to a source (S) of breathable air. It is equipped with a mouth and nose mask (3) with an intake (4) for the breathable air inside the suit, and a valve (5) for evacuating used air through a tube (9) and outlet (6). A second outlet (7) with a valve (7a) allows rapid release of surplus air from the suit. The breathable air source can be a container of compressed air or a system for filtering outside air to remove pollution. The mask intake can also be fitted with a filter.

Description

 The invention relates to a device for protecting a subject evolving in a polluted environment, while preserving his mobility and his breathing.

 It is known to protect a subject evolving in a polluted atmosphere by enclosing him in an air suit consisting of a flexible and waterproof integral envelope preserving his motor skills, means being provided for introducing breathable air inside the 'envelope.

The breathing function can be, in a known manner, provided by:
A. Regeneration of the air contained in the spacesuit
by elimination of carbon dioxide and contribution
oxygen,
B. Supply of compressed air distributed to the diver
by a pneumatic device called on demand,
the exhaled gases being discharged into the spacesuit,
which, in order not to increase in volume, comprises
an overflow valve.

C. Provision of a continuous air flow in the
diving suit, high enough flow so that
the subject's CO2 released by breathing is diluted
to the point that the average C02 level in the
diving suit remains below the normalized threshold of 1%.

Sophisticated method A requires devices
regulating oxygen flows and a filter
special for absorbing carbon dioxide.

Method B assumes an air supply under a flow
potential equal to the maximum peak inspiratory flow of the
subject either> 3001 / min. for an average ventilation of
1001 / min.

 Method C, so as not to exceed a maximum carbon dioxide rate of 1 * i, must receive a continuous flow of at least 200 l / min.

 The present invention provides a solution which makes it possible to limit the supply of air to a flow rate equal to the average ventilation, the air contained in the spacesuit remaining free of carbon dioxide.

 This is achieved according to the invention, by incorporating into the device an oronasal mask capable of being worn by the subject inside the envelope, said mask being provided with an air inlet communicating with the interior of the envelope under the control of an inspiratory valve and being provided with an air outlet communicating with the outside of the envelope under the control of an exhalation valve to evacuate the air exhaled by the subject.

In advantageous embodiments, the device also has one or more of the following characteristics:
-the said envelope has a connected air outlet
by a sealed duct at the air outlet of the mask,
-the said envelope has a second outlet
air fitted with a calibrated valve to ensure
the rapid escape of any overflow of air
inside the envelope,
-the said envelope is provided with an air inlet
connected by a sealed duct to an air source
outside the envelope,
- said air source ensures a continuous flow
of breathing air at least equal to the average of the
subject's expiratory flow,
the breathing air source is an air network
compressed,
the breathing air source is a ventilator
portable vacuum cleaner that takes outside air,
filter it off and send it to the
clothes,
the oronasal mask includes at the inlet of the valve
an additional safety filter.

 The use of a simple fan constitutes a preferred embodiment.

 In fact, except in the event of a fire where the ambient air may have a lower than normal oxygen content, the ambient air, even polluted, generally contains 21% of oxygen and is breathable if it is filtered. The gas masks are made for this but the pressure losses due to the filters penalize breathing. In the solution according to the invention, the pressure drop, taken into account only by the fan, is reduced by the maximum peak flow / average flow ratio, namely, by a factor of at least 3.

 A description of such an embodiment will be described below, with reference to the single figure of the attached drawing which diagrammatically represents a diving suit consisting of a flexible integral envelope 1 in which there is a subject wearing an oronasal mask 3.

 The suit is supplied with breathable gas (for example oxygen or air) through a conduit 8 which comes from a source S of breathable gas and which leads to an inlet 2 of the envelope 1.

 The envelope has a gas outlet 7 provided with an overflow valve 7a.

 The mask is provided with a gas inlet 4 equipped with an inspiratory valve and which opens into the envelope, and with a gas outlet 5 equipped with an expiration valve and which is connected by a sealed conduit 9 to a output 6 of envelope 1.

 The source S is, for example, an electric fan, the air intake outlet of which is fitted with a filter suitable for cleaning up the air taken up by the fan.

 The invention is not limited to this embodiment.

 It applies in particular to subjects evolving in atmospheres polluted by gases or dust. (C02, asbestos, radioactivity, etc.).

Claims (8)

 evacuate the air exhaled by the subject.  under the control of an exhalation valve for  (5) communicating with the outside of the envelope  an inspiratory valve and an air outlet  with the inside of the envelope under control  being provided with an air inlet (4) communicating  subject inside the envelope, said mask  oronasal mask (3) able to be worn by a  characterized in that the device comprises a  envelops a gas containing breathable air,  (5,8,2) to introduce inside  allowing him to move and means  waterproof able to contain the entire subject and  consisting of a flexible integral envelope (1) and  breathing, which involves an air suit  polluted by preserving its mobility and  CLAIMS 1) Device to protect a subject in the middle 2) Device according to claim 1, wherein said  envelope (1) has an air outlet (6)  connected by a sealed conduit (9) to the outlet  air (5) from the mask. 3) Device according to claim 1, wherein said  envelope (1) has a second air outlet  (7) provided with a valve (7a) calibrated to ensure  the rapid escape of a possible overflow  of air inside the envelope. 4) Device according to one of claims 1 to 3  where said envelope (1) is provided with an inlet  air (2) connected by a duct (8) to a source  air (S) outside the envelope. 5) Device according to claim 4 wherein said  air source (S) provides continuous air flow  breathable at least equal to the average flow  expiratory of the subject. 6) Device according to claim 4 or 5, wherein the  air source (S) is a compressed air network. 7) Device according to claim 4 or 5, wherein the  air source (S) is a vacuum fan  portable that extracts outside air, cleans it up  by filtering and sends it to the garment. 8) Device according to one of claims 1 to 7,  where the oronasal mask has at the input of the  inspiratory valve (4) an additional filter  of security.