GB2422426A

GB2422426A - Clean air apparatus

Info

Publication number: GB2422426A
Application number: GB0525583A
Authority: GB
Inventors: Stephen Edworthy; Paul Alan Riley
Original assignee: ATLAS CLEAN AIR Ltd
Current assignee: ATLAS CLEAN AIR Ltd
Priority date: 2004-12-16
Filing date: 2005-12-16
Publication date: 2006-07-26
Also published as: GB0525583D0; GB0427666D0

Abstract

A clean air apparatus 1 comprises a filtering unit 2 having an inlet for taking in air, a filter for the removal of contaminants from the air and expelling the air through an outlet (20, fig 2) into an adjacent environment 3, an adjustable device 5 for mounting the filtering unit 2 relative to a support structure, and the adjusting device 5 permitting manoeuvring of the filtering unit 2 to a position where clean air is required. Environment 3 may be enclosed by a transparent curtain 4 that may be rigid, semi-rigid or flexible, may be removable or disposable, may have a central cutaway 30 to permit access, and may have pockets 32 for the storage of sterile dressings and implements for use in the environment 3. Unit 2 may comprise of a fan housing 6 having a fan mounted on plate (15), a filter housing 7 having a replaceable HEPA filter held between upturned extensions (22) of a peripheral rim (22) around outlet (20), and lights disposed in lighting housings 8 which shine through a translucent cover plate (26). The support structure may be fixed to a building or comprise a moveable stand (34, fig 4). Adjustable device 5 may comprise an arm formed in two or more parts with at least one pivotable joint (33b, fig 3). The apparatus 1 may be used alongside hospital beds and suitable for wound management.

Description

CLEAN AIR APPARATUS

This invention relates to clean air apparatus to establish a clean air environment in particular, although not exclusively for use in surgical or medical procedures such as wound management.

Conventionally, clean air environments are used in a variety of industries e.g. food processing, electronics manufacturing and pharmaceutical manufacturing, to prevent contamination of products by air- borne particles.

Such clean air environments are achieved in enclosed working areas by installations which create a filtered laminar air flow where air is passed through a filter and expelled as clean/sterile air into the working area before being recycled through the filter.

Clean air environments are also used in hospitals, particularly in * I. enclosed sterile treatment rooms such as operating theatres, to avoid I. 1 5 infection by air-borne contaminants. Fixed overhead air filtration and * recirculation units are used to provide a curtain of downwardly directed clear air streams within the room.

:..::: There is a requirement for precautionary measures to prevent crosscontamination in hospitals in relation to invasive medical and surgical procedures performed outside sterile rooms, such as handling of open wounds (wound management) in hospital wards.

There are numerous infections acquired by patients while they are in hospital and due to the high level of antibiotic use some bacteria become resistant e.g. Methicillin-Resistant Staphylococcus Aureus (MRSA). This makes hospital-acquired infections potentially dangerous and sometimes life-threatening. As a result of this, higher standards of cleanliness are being called for.

As a consequence, it is common practice for example, to provide washing facilities and disinfectants alongside patients' beds for use by nursing staff when attending to wounds. This does not however deal with air-borne infection. This could be addressed by attending to wounds within sterile rooms but from a cost and convenience perspective that may not always be feasible.

An object of the present invention is to provide apparatus whereby a clean air environment can be established inexpensively and conveniently suited to localised use particularly for performing invasive medical or surgical procedures such as the handling of open wounds.

1 5 According to one aspect of the invention therefore, there is a a provided a clean air apparatus comprising a filtering unit having an inlet for taking in air, a filter for removal of contaminants from said air and a a:: :* means for expelling resultant clean air through an outlet into an adjacent environment, characterised by the provision of an adjustable device for mounting the filtering unit and the enclosing structure relative to a support structure, the adjustable device being adapted to permit manoeuvring of the filtering unit and enclosing structure into a localised position where clean air is required.

With this arrangement, a clean air environment can be readily established at a localised position e.g. around a patient's wound, or a part of a patient's body where a simple invasive medical or surgical procedure is to be performed. The clean air environment can therefore be defined in a convenient and inexpensive manner without relying on expensive installations in sterile rooms whereby, suitably, the apparatus may be provided, for example, on a temporary or permanent basis alongside a patient's bed in a hospital ward or within a non-sterile treatment room or the like.

Preferably, the unit is suspended by the adjustable device particularly such that the unit is supported on the supporting structure only or substantially only via the adjustable device with the unit uppermost and the said outlet directed downwardly whereby the clean air * . . is directed downwardly into the said environment.

1 5 If desired an enclosing structure may be mounted relative to said * unit to define an enclosed said environment. Where the unit is suspended * * as aforesaid the enclosing structure may be supported with the unit only * or substantially only via the adjustable device on the supporting structure so as to depend from the unit.

The enclosing structure may be rigid, semi-rigid or freely flexible and may be adapted to enclose wholly the environment i.e. such that access is only possible through an openable section such as a flap or the like, or it may only partially enclose the environment so that it has a free opening thereto.

In one embodiment the said enclosing structure comprises a depending flexible curtain with a free bottom opening thereto.

Thus, according to a second aspect of the invention which may be combined with the first aspect, there is provided a clean air apparatus comprising a filtering unit and an enclosing structure mounted relative to said unit to define an enclosed environment, said filtering unit being positioned above said environment and having an inlet for taking in air, a filter for removal of contaminants from said air and a means for expelling resultant clean air through an outlet into said environment, characterised in that said apparatus is manoeuvrable into a position where clean air is required and said enclosing structure is a flexible structure with an open bottom end thereto.

II

With this arrangement the apparatus can be readily positioned over 1 5 a wound or an area which is to undergo any invasive medical or surgical * procedure, to provide a clean air environment prior to the opening up of the wound or embarking on the invasive procedure, thereby improving cleanliness and reducing the chance of cross-contamination. *41

With the first and second aspects of the invention the filtering unit may comprise a fan housing disposed above a lower filter housing such housings containing respectively the said means of expelling comprising a fan and the filter. A lighting unit may also be provided to direct illumination into the said environment. This lighting unit may be attached to the filtering unit or may be integrated therewith.

A control panel may be mounted on the filtering unit for controlling the operation of the clean air apparatus, e.g. by controlling switching on and off of the aforesaid fan and lighting unit.

Provision may be made for connection of the apparatus to a separate power supply via a power cable. Alternatively, an internal battery power supply may be provided.

Where the enclosing structure is flexible as aforesaid this may be defined by a drape or curtain of flexible material such as a non- permeable plastics sheet material (e.g. PVC). The drape may extend wholly around the periphery of the filtering unit so as to be closed on each side. One side may be cut away or may have a flap or the like to facilitate access.

Most preferably, the enclosing structure has at least one viewing portion to allow inspection of the environment through the enclosing 1 5 structure. Thus, the enclosing structure may be transparent or may have a transparent window therein.

In addition, at least one pocket may be provided within the enclosing structure for storage of articles such as sterile dressings or implements for use in the environment.

The enclosing structure may be removable for disposal and replacement.

Where the filtering unit and the enclosing structure are adapted for mounting on a support structure via an adjustable mounting device, as aforesaid, the support structure may be a fixed building structure such as a wall or ceiling alongside a patient's bed and the mounting device may comprise an arm with a movable preferably pivotable joint or joints between two or more parts thereof and/or one or more extendable or displaceable parts to permit positional adjustment of the filtering unit and enclosing structure, such adjustment being vertical (for height) and/or angular (for inclination) and/or laterally (to move the filtering unit and enclosing structure towards and away from the support structure). There may also be capability of sufficient positional adjustment to move the filtering unit and enclosing structure between operational and stowed positions. In the stowed position the filtering unit and enclosing structure may be on or close to the support structure.

Alternatively, the filtering unit and the enclosing structure may be :: mounted on a movable stand such as a wheeled stand so that positional 1 5 adjustment is achieved by moving this stand and/or by adjusting a 5 suspension structure of the stand.

The invention will now be described further by way of example 1: only and with reference to the accompanying drawings in which: Figure 1 is a diagrammatic perspective view of one form of a clean air apparatus according to the invention; Figure 2 is a cross-sectional view of the apparatus of Figure 1; and Figures 3 and 4 are perspective views of a modified version of the arrangement of Figure 1.

According to one embodiment of the invention shown in the drawings, a clean air apparatus 1 comprises a filtering unit 2 and an environment 3 defined by an enclosing structure 4. The filtering unit 2 is suspended from an adjustable mounting device 5 attached to a support structure (not shown) whereby the unit 2 is positioned above the environment 3 with the unit 2 extending horizontally and the structure 4 hanging downwardly therefrom, the unit 2 and structure 4 being separate from the support structure and supported thereon only via the mounting device 5.

The filtering unit 2 comprises an upper rectangular box-shaped fan housing 6 disposed above a lower rectangular box-shaped filter housing * S. 7, and two rectangular box-shaped lighting housings 8 disposed respectively along two opposite sides of said filter housing 7. The fan * 1 5 housing 6 is tack welded at contacting points to the filter housing 7, the filter housing 7 being tack welded to the lighting housings 8 at contacting points.

The fan housing 6 has a rectangular top wall 9 which has an opening 10 in its central region, four rectangular downwardly projecting sides 11, and a rectangular base wall 1 2, the base wall 1 2 containing an off-centre rectangular aperture 13.

A fan (not shown) is mounted within the fan housing 6 on a mounting plate 1 5 fixed to one side 11 a. The fan is operable to draw air in through the central opening 10 of the top wall 9 and expel this downwardly through the aperture 1 3 preferably providing a laminar air flow. A power supply is provided to the fan via a power cable (not shown).

The central opening 10 of the top wall 9 is covered with an air permeable covering or grid.

A control panel 1 6 is mounted on the fan housing 6 of the filtering unit 2 for controlling operation of the fan with appropriate electrical switches.

The filter housing 7 has a rectangular top wall 17 which has a central opening 1 8 and four rectangular downwardly projecting sides 1 9.

* The base 20 of the housing being generally open.

The central opening 18 of the top wall 17 is bounded by a peripheral inturned flange 21.

* 1 5 The open base 20 is bounded by a peripheral rim 22 defining an outlet. The rim 22 has four upturned extensions 23 respectively located * I,.

* at a central position on each of the four sides of the base 20.

A filter (not shown) is held in place within the filter housing 7 over the outlet defined by the open base 20 between the extensions 23 such that air expelled through the aperture 1 3 passes through the filter, and clean air is expelled through the outlet of the open base 20.

The filter is a HEPA (High Efficiency Particulate Air) filter which conforms with standard EN 1822-1 1998 (Class H14), providing air cleanliness levels as defined in ISO 14644-1 1999 and is in the form of a panel which is replaceable.

The lighting housings 8 each has a rectangular top waIl 24, four downwardly projecting sides 25, and an open base 26.

The outermost long side 25 is rectangular and has an aperture 27 along its length which is covered by a removably attached plate 1 8 with an inwardly projecting flange 29.

The open base 26 is covered with a translucent cover plate.

The inner flange 29 provides a mounting means for a lamp (not shown). The lamp is connected to the power cable for the fan via the control panel 1 6 whereby operation of the lamp can be controlled by an appropriate switch on the panel. The lamp is positioned such that, when $ I. switched on, light is directed downwardly through the translucent cover plate in the open base 26. * I I

* 1 5 The structure 4 defining the environment 3 is a one-piece non-rigid :. structure and comprises a curtain or drape of flexible translucent PVC with good optical quality, which extends wholly around the unit 2. The curtain is fixed at its top edge region along the lower edges of the outer walls of the lighting housings 8 and along the lower edges of the front and rear sides of the side walls of the filter housing 7 and the adjacent end walls of the lighting housings 8.

The curtain thereby has four rectangular sections which have straight edges, the top edges and the bottom edges lying in respective planes. The top edges bound an open top to the structure 4 which is closed or covered by the unit 2. The bottom edges 31 bound an open bottom to the structure 4 which remains freely open.

The front section has a central cutaway part 30 at its lower edge region.

Two pockets 32 are provided in the inside middle region of one of the side sections of the structure 4.

The drape can be detached for disposal and replacement.

The aforesaid adjustable mounting device 5 may comprise an adjustable arm attached to the filtering unit 2 at one end and attached at the other end to a fixed wall or ceiling structure. The arm is mounted via joints 33 on the unit 2 and/or the wall or ceiling structure and/or is articulated with separate arm sections linked by internal joints so that the unit and the structure can be manoeuvred into a desired position. The (or * 15 each) joint may comprise a hinge or pivot joint with a vertical axis whereby the unit 2 and structure 4 are retained in the aforementioned horizontal/vertical disposition at a fixed height throughout manoeuvring. I, I*

Other movements are however also possible. Thus, there may be an extendable link or other adjustable joint or section, e.g. a parallelogram linkage to permit height adjustment. Also, there may be a ball joint or universal joint to permit change in inclination out of the horizontal/vertical disposition in one or more planes.

A locking device may be provided to lock the adjustable mounting device in an adjusted position. Thus a screw or other tightening means may be provided to fix relatively movable parts as by friction gripping or an abutment or the like. Alternatively or additionally a movement resisting hydraulic cylinder or counterbalance spring or the like may be provided.

The apparatus so far described may be used in a hospital ward whereby the wall or ceiling structure to which the arm is attached may be behind or adjacent to a patient's bed.

Alternatively, the adjustable mounting device, which may be an arm as described above or other device, may be attached to a wheeled stand which can be brought to a patient as and when required.

With this arrangement, during wound management for a patient in * I. :::: the bed provided with the apparatus the unit 2 and structure 4 are manoeuvred into position so that the wound is located within the 1 5 confines of the open bottom end of the drape, the flexibility of the drape readily permitting close contact between the drape and the patient's body around the wound.

The filtering unit is then switched on to replace the air in the environment 3 with clean air. The lamps in the lighting housing 8 are also switched on to illuminate the environment. The wound can now be treated, e.g. by opening up the wound or removing a dressing, working through the cut away section 30. The laminar air flow ensures minimum disruption in the work environment. Conveniently fresh dressings or other articles can be stored in the pockets 32. The unit 2 remains switched on to maintain the clean air environment until the procedure is complete and the open wound is covered. The apparatus can then be moved away and, if desired, the drape can be removed and replaced prior to the apparatus being used on another patient. The unit can be easily manoeuvred out of the way when not in use and in use can be usefully manoeuvred over an area to be treated.

Since the apparatus is of relatively small size and low power suited to localised use, rather than large scale sterile room use or the like, it can be relatively inexpensive and convenient to use and install.

Instead of using a readily flexible, loose hanging drape, a curtain which is semi-rigid, or wholly rigid may be used. In this case, if desired the unit and structure need not be suspended vertically but may be at any desired angle to the vertical.

1 5 The arrangement shown in Figures 3 and 4 is similar to that of Figures 1 and 2, and the same reference numerals are used for corresponding parts. However, the enclosing structure 4 is wholly omitted. Instead the clean air environment 3 is defined simply by virtue of the clean air flow taking place downwardly from the outlet 1 3 of the fan housing 6 to exit through the open bottom of the filter housing 7.

This downward flow of air is sufficient to maintain a clean air environment below the fan housing 6 at least over the cross-sectional area of the housing. An effective clean air environment up to 500mm below the housing is readily attainable.

As shown in Figures 3 and 4, the unit 2 is suspended from a wheeled stand 34 via an arm 5 fixed to the fan housing 6 via a stirrup member 35 with two joints 33a, 33b in the arm 5 permitting pivoting about vertical axes, and an adjustable, lockable link 33c between the arm and an upright 36 of the stand 34 permitting height adjustment.

One of the pivot joints 33a permits movement of a forward part of the arm relative to a rearward part so that the unit can swing from side to side, whereas the other joint 33b permits rotation of the unit about a vertical axis centrally through the unit.

A grab handle 37 is provided on the front of the unit 2 to facilitate adjustment of the position of the unit 2 on the stand by pivoting around the joints 33a, 33b and by varying height with the link 33b.

It is of course to be understood that the invention is not intended * * 1 5 to be restricted to the details of the above embodiment, which is described by way of example only.

Thus, for example, although it is visualised that the apparatus will find particular application in bed side wound management other applications are also possible. The apparatus may be used at hospital locations other than bedside, it may be used for medical or surgical procedures other than wound management, and it may be used other than in hospitals.

Claims

1. A clean air apparatus comprising a filtering unit having an inlet for taking in air, a filter for removal of contaminants from said air and a means for expelling resultant clean air through an outlet into an adjacent environment, characterised by the provision of an adjustable device for mounting the filtering unit and the enclosing structure relative to a support structure, the adjustable device being adapted to permit manoeuvring of the filtering unit and enclosing structure into a localised position where clean air is required.

2. Apparatus according to claim 1 characterised in that the unit is suspended by the mounting device.

3. Apparatus according to claim 2 characterised in that the unit is supported on the supporting structure at least substantially only via 1 5 the mounting device with the unit uppermost and the said outlet directed downwardly.

4. Apparatus according to any one of claims 1 to 3 characterised in that an enclosing structure is mounted relative to said unit to define an enclosed said environment.

5. Apparatus according to claim 4 characterised in that the enclosing structure comprises a depending flexible curtain with a free bottom opening thereto.

6. Apparatus according to claim 5 characterised in that the curtain is removable.

7. Apparatus according to claim 5 or 6 characterised in that the curtain has at least one viewing portion.

8. Apparatus according to any one of claims 1 to 7 characterised in that the filtering unit comprises a fan housing disposed above a lower filter housing.

9. Apparatus according to any one of claims 1 to 8 characterised by the provision of a lighting unit to direct illumination into the said environment.

10. Apparatus according to any one of claims 1 to 9 characterised in that the support structure is a fixed building structure.

11. Apparatus according to any one of claims 1 to 9 characterised in that the supporting structure comprises a movable stand.

1 2. Apparatus according to any one of claims 1 to 11 characterised in S. .5 that the adjustable device comprises an arm.

1 3. Apparatus according to claim 1 2 characterised in that the arm is S formed in two or more parts with at least one movable joint S.,.

therebetween.

1 4. Apparatus according to claim 1 3 characterised in that the (or at least one) said joint is a pivotable joint.

1 5. A clean air apparatus comprising a filtering unit and an enclosing structure mounted relative to said unit to define an enclosed environment, said filtering unit being positioned above said - 16- environment and having an inlet for taking in air, a filter for removal of contaminants from said air and a means for expelling resultant clean air through an outlet into said environment, characterised in that said apparatus is manoeuvrable into a position where clean air is required and said enclosing structure is a flexible structure with an open bottom end thereto.

1 6. A clean air apparatus substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings. * *. *1*a *. .. * * S 6 6

S S IS,,