1、BRITISH STANDARD BS 7672:1993 Specification for Compression, stiffness and labelling of anti-embolism hosiery UDC 615.477.5BS7672:1993 This British Standard, having been prepared under the directionof the Health Care Standards Policy Committee, waspublished under the authorityof the Standards Boarda
2、nd comes into effect on 15September1993 BSI 10-1999 The following BSI references relate to the work on this standard: Committee referenceHCC/39 Draft for comment92/55311 DC ISBN 0 580 21848 1 Committees responsible for this British Standard The preparation of this British Standard was entrusted by t
3、he Health Care Standards Policy Committee (HCC/-) to Technical Committee HCC/39, upon which the following bodies were represented: British Medical Association British Retail Consortium Consumer Policy Committee of BSI Department of Health Knitting Industries Federation Ltd. Malaysian Rubber Producer
4、s Research Association National Association of Medical and Surgical Appliance Officers Surgical Appliance Manufacturers Association Surgical Dressings Manufacturers Association Textile Research Council (HATRA) Vascular Surgical Society of GB Coopted experts Amendments issued since publication Amd. N
5、o. Date CommentsBS7672:1993 BSI 10-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 References 1 3 Definitions 1 4 Compression 1 5 Durability of compression after repeated washing 1 6 Stiffness 1 7 Marking and labelling 2 Annex A (normative) Method of test for c
6、ompression value and stiffness of anti-embolism hosiery 3 Figure A.1 Compression testing machine 4 Figure A.2 Back face of measurement head 5 Figure A.3 Side view of jig mounted on the measurement head 6 Figure A.4 Apparatus for calibrating the measurement head 7 Table A.1 Girths of the adjustable f
7、ormer 5 Table A.2 Positions for setting up garments for testing 7 List of references Inside back coverBS7672:1993 ii BSI 10-1999 Foreword This British Standard has been prepared under the direction of the Health Care Standards Policy Committee. Anti-embolism hosiery is intended for use during surgic
8、al operations and on patients confined to bed, as a prophylaxis to prevent the formation of deep venous thrombosis. Anti-embolism hosiery may be less effective for non-ambulant patients not in bed. The garments are based on synthetic elastomeric yarns. Relief of the symptoms of some medical conditio
9、ns may require the higher levels of compression supplied by medical compression hosiery specified in BS6612. The test method described in this British Standard for determining compressive capabilities of hosiery is based on the MarkII hose pressure tester which incorporates an adjustable flat-bed fo
10、rmer. This method was selected after a series of laboratory tests, including a comparison with other methods and an extended interlaboratory trial of several testing machines. The advantages of thismethod were considered to be that calibration was straightforward, that the dimensions at which tests
11、may be conducted could, within limits, be varied andthat the test was rapid and convenient for manufacturers. Sufficient precision/reproducibility and repeatability were evident during the comparative tests to warrant adopting the method in this British Standard. The standard is expected to provide
12、a basis for further clinical and physiological evaluation of anti-embolism hosiery so that in the future the clinical efficacy of garments may be related more reliably to the compression which they exert in wear. The standard is not intended to imply that only garments with these particular qualitie
13、s are those which are effective in a clinical disorder. It is expected that as a result of publication of this standard the clinical relevance of the features which have been identified will be defined more clearly. Attention is drawn also to the method of test for non-prescriptive graduated support
14、 hosiery given in BS7563. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of page
15、s This document comprises a front cover, an inside front cover, pages i and ii, pages1 to 10, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.B
16、S7672:1993 BSI 10-1999 1 1 Scope This British Standard specifies requirements for, and describes Methods of test for, the compression and stiffness of anti-embolism hosiery. It also specifies labelling requirements. 2 References 2.1 Normative references This British Standard incorporates, by referen
17、ce, provisions from specific editions of other publications. These normative references are cited at the appropriate points in the text and the publications are listed on the inside back cover. Subsequent amendments to, or revisions of, any of these publications apply to this British Standard only w
18、hen incorporated in it by updating or revision. 2.2 Informative references This British Standard refers to other publications that provide information or guidance. Editions of these publications current at the time of issue of this standard are listed on the inside back cover, but reference should b
19、e made to the latest editions. 3 Definitions For the purposes of this British Standard, the following definitions apply. 3.1 anti-embolism hosiery hosiery which, when worn on the leg, exerts graduated compression on the leg surface and is intended to reduce the incidence of deep venous thrombosis in
20、 non-ambulant patients 3.2 nominal compression value a single nominal compression figure characterizing the compression performance of a garment at the ankle NOTEThe compression value is assigned by the manufacturer on the basis of measurements on similar garments and is equal to the compression whi
21、ch the garment is intended to exert at the ankle when worn on a leg of a designated size. 3.3 compression profile the pressure exerted by the hosiery along the leg it is intended to fit 3.4 stiffness a measure of the change in the compression exerted by a garment when the girth is increased or decre
22、ased from that designated by the manufacturer by an amount equivalent to a change in the size of the adjustable former of the compression testing machine by one position NOTESeeA.2.1. 3.5 normal measuring positions the positions at the ankle, calf and thigh of a garment at which compression is to be
23、 measured NOTETesting of designated sizes is achieved by use of test equipment which simulates human leg dimensions. Details of the set-up procedure and the corresponding girths are given inAnnex A. 4 Compression When tested by the method described inAnnex A: a) the compression value at the ankle sh
24、all be not less than1.34kPa 1) (10mmHg) and not more than2.4kPa(18mmHg); b) the compression value at the calf shall be not more than80% of that at the ankle, and shall be not less than1.07kPa(8mmHg) and not more than1.87kPa(14mmHg); c) the compression value at the thigh, if present, shall be not mor
25、e than80% of that at the calf; d) the actual compression at the ankle shall not differ by more than 20% from the nominal compression value stated by the manufacturer see7.1 d). 5 Durability of compression after repeated washing After completing30 washes in accordance with the wash procedure of BS492
26、3:1991 stated in the manufacturers instructions see7.1 k), and after drying flat as defined in BS4923:1991, each measuring position of the garment shall retain at least85% of the compression which it exerted before this series of washes. 6 Stiffness When tested by the method described inAnnex A, the
27、 stiffness at any measuring position shall be not greater than25%. 1) 1kPa = 7.5mmHg.BS7672:1993 2 BSI 10-1999 7 Marking and labelling 7.1 The package or a leaflet contained within the package shall contain at least the following information: a) manufacturers or distributors name; b) size of garment
28、; c) manufacturers colour code; d) nominal compression value (see3.2); e) leg length range in centimetres; f) ankle girth range in centimetres; g) calf girth range in centimetres; h) upper thigh girth range in centimetres; i) fibre content; j) washing and care instructions; k) identification of the
29、procedure chosen from BS4923:1991 by the manufacturer to be used for the wash performance test specified in clause5, making clear that the procedure is for test purposes only; l) instructions for storage, fitting and use. 7.2 The garment shall be marked with, or shall bear a label giving, at least t
30、he following information: a) manufacturers or distributors name or logo; b) size of garment; c) manufacturers colour code. NOTEThe garment or label should also be marked with the symbol(s) denoting the relevant washing and care instructions.BS7672:1993 BSI 10-1999 3 Annex A (normative) Method of tes
31、t for compression value and stiffness of anti-embolism hosiery A.1 Principle The garment is loaded onto an adjustable former, simulating the wearing of the garment on a human leg. A measuring head pressed against the stretched fabric at various points along the length of the adjustable former is use
32、d to determine and display a value for the circumferential tension in the fabric. This value is converted to a value for compression. By changing the size of the former, measurements are made of the stiffness of the garment, i.e.the extent to which compression changes with girth. For a fuller descri
33、ption of the functioning of the apparatus see Peat1. A.2 Apparatus A.2.1 Hosiery compression testing machine, comprising two main parts: the adjustable former and the measurement head, and having the features described as follows and illustrated inFigure A.1. a) Adjustable former, comprising the fol
34、lowing. 1) A flat former, consisting of two metal bars arranged to give a simplified leg form, the movable top bar of which can be lowered by a hand lever to enable the garment to be loaded. 2) Pivots at each end of the former which can be moved to different holes to enable the former to adopt any o
35、ne of the girths given inTable A.1. 3) A fixed lower bar having two curved attachments simulating the calf and thigh with clips attached to the movable top and fixed lower bars carrying conventional suspender-type fasteners to hold the garments, the clips being movable along the bars to hold garment
36、s at the correct position according to size. 4) A traverse rail having marked positions to which the measurement head is set, the marked positions locating the measuring positions at100,290,310,330,530,600 and670mm from the sole point. 5) A sole point, representing the sole of the foot on former set
37、ting number4, lying at the intersection of the line of the sole (see inset inFigure A.1) of the simulated foot with a line midway between the outer surfaces of the movable top and fixed lower bars. b) Measurement head comprising the following. a) A movable tongue25mm wide and a guard plate which pre
38、vents excessive movement of the tongue, and designed so as to be sensitive to tension in the garment only in the circumferential direction (seeFigure A.2). b) A motor within the head which balances the force exerted by the fabric on the tongue. c) A digital display which shows a reading proportional
39、 to the fabric tension. A.2.2 Jigs for checking setting of the measurement tongue, as shown inFigure A.3. A.2.3 Feeler gauge, of thickness(0.075 0.01)mm. A.2.4 Equipment for calibrating the measurement head, comprising a pin, spring, tape, reference weight of mass(400 2)g and a small screwdriver for
40、 adjusting the two potentiometers. NOTEThe equipment is shown mounted on the compression test machine inFigure A.4. A.3 Preparation of apparatus A.3.1 Checking the setting of the measurement tongue NOTEThe measurement head is illustrated inFigure A.2. Check the setting of the measurement tongue in r
41、elation to its guard plate at intervals of not more than3months and whenever the head is knocked or otherwise mishandled, using the following procedure. a) Slide the jig supplied with the instrument(A.2.2) over the top of the measurement headA.2.1 b) as shown in Figure A.3 so that the brass plate in
42、side the jig contacts the guard plate at each side. b) Read the display by pressing the operating button. c) Insert the feeler gauge(A.2.3) between the brass plate and the measurement tongue and read the display again. d) If the reading without the feeler gauge is more than200, or the reading with t
43、he feeler, gauge is less than200, the head is out of alignment and the supplier of the instrument should be consulted. NOTEThe reading is a dimensionless number.BS 7672:1993 4 BSI 10-1999 Figure A.1 Compression testing machineBS7672:1993 BSI 10-1999 5 Table A.1 Girths of the adjustable former Dimens
44、ions in millimetres Measuring position (distance of measurement head from sole point) Girths of the former at former setting number a 1 2 3 4 5 6 7 Ankle: all sizes(100) 172 187 204 223 243 265 288 Calf: short (290) 282 302 322 346 370 397 426 Calf: regular (310) 289 309 330 354 379 406 436 Calf: lo
45、ng (330) 296 316 338 362 388 415 446 Thigh: short (530) 351 376 403 432 462 495 531 Thigh: regular (600) 379 406 434 464 497 532 569 Thigh: long (670) 402 430 461 493 527 564 603 a Girths at other positions can be obtained by measurement of the former (seeA.4.5) Figure A.2 Back face of measurement h
46、eadBS7672:1993 6 BSI 10-1999 A.3.2 Calibration of the measurement head When the machine is in use, calibrate the measurement head once a day by the following procedure. a) Remove the lower suspender clip plate, set the former to setting number6 and raise the movable top bar by means of the raising b
47、ar. b) Take the calibration assembly of pin, spring, tape, and reference weight(A.2.4), and insert the pin in the horizontal hole in the movable top bar, adjacent to suspender clip hole number1. Allow the weight to tension the tape hanging across the face of the fixed lower bar, with the bottom of t
48、he weight suspended about25mm higher than the traverse rail as shown inFigure A.4. Adjust the pin, further into or out of the hole to allow the tape to hang very close to the fixed lower bar, but not to touch it. Allow the tape to hang for not less than3min prior to the next step. c) Set the zero by
49、 sliding the head to a position towards the ankle end of the traverse bar at a distance of about150mm from the tape; move the head into contact with the fixed lower bar, and press the operating button to take a reading. Adjust the zero potentiometer to give a reading of000. d) Set the scale by tilting the head away from the fixed lower bar and slide it along to line up the tape with the centre of the head. If the reference weight is disturbed, steady it from swinging before proceeding. Move the head towards the fixed lower bar to contact
