BS-EN-13726-1-2002.pdf

BRITISH STANDARD BS EN 13726-1:2002 Test methods for primary wound dressings Part 1: Aspects of absorbency The European Standard EN 13726-1:2002 has the status of a British Standard ICS 11.120.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 08:52:15 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 13726-1:2002 This British Standard, having been prepared under the direction of the Health and Environment Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 15 April 2002 © BSI 15 April 2002 ISBN 0 580 39510 3 National foreword This British Standard is the official English language version of EN 13726-1:2002. The UK participation in its preparation was entrusted by Technical Committee CH/117, Medical textiles, to Subcommittee CH/117/1, Test methods for non-wovens for use in compresses, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. 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. aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 16, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. DateComments Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 08:52:15 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN 13726-1 March 2002 ICS 11.120.20 English version Test methods for primary wound dressings - Part 1: Aspects of absorbency Méthodes d'essai pour les pansements primaires en contact avec la plaie - Partie 1: Absorption Prüfverfahren für primäre Verbandstoffe (Wundauflagen) - Teil 1: Aspekte des Saugverhaltens (Absorption) This European Standard was approved by CEN on 25 February 2002. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels © 2002 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13726-1:2002 E Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 08:52:15 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13726-1:2002 (E) 2 Contents page Foreword3 Introduction.4 1Scope 5 2Terms and definitions5 3Test methods for absorbency.5 3.1Test conditions 5 3.2Free swell absorptive capacity.5 3.3Fluid handling capacity (absorbency plus moisture vapour transmission rate, liquid in contact).7 3.4Fluid affinity of amorphous hydrogel dressings8 3.5Gelling characteristics 11 3.6Dispersion characteristics12 3.7Dispersion/solubility of hydrogel dressings.13 Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 08:52:15 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13726-1:2002 (E) 3 Foreword This document EN 13726-1:2002 has been prepared by Technical Committee CEN/TC 205 “Non-active medical devices“, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2002, and conflicting national standards shall be withdrawn at the latest by September 2002. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). EN 13726 will consist of the following parts under the general title Test methods for primary wound dressings: - Part 1 : Aspects of absorbency - Part 2 : Moisture vapour transmission rate of permeable film dressings - Part 3 : Waterproofness - Part 4 : Conformability - Part 5 : Bacterial barrier properties - Part 6 : Odour control According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 08:52:15 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13726-1:2002 (E) 4 Introduction EN 13726 specifies test methods and does not contain performance requirements. Part 1 of this standard describes test methods for different aspects of absorbency. Test methods for other aspects of primary wound dressings are described in other parts of EN 13726. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 08:52:15 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13726-1:2002 (E) 5 1 Scope Part 1 of EN 13726 specifies test methods recommended for the evaluation of some aspects of absorbency of primary wound dressings. 2 Terms and definitions For the purposes of this European Standard the following terms and definitions apply. 2.1 alginate dressing dressing containing salts of alginic acids which interact with physiological fluids to form a gel 2.2 amorphous hydrogel semi-solid gel that contains hydrophilic polymers and water 2.3 fluid affinity of a wound dressing ability to absorb fluid from or donate fluid to a simulated wound 2.4 fluid handling capacity sum of the fluid absorbed and the fluid transpired through the dressing 2.5 free swell absorptive capacity total absorptive capacity in the presence of excess test liquid and in the absence of any applied load 2.6 primary wound dressing material or combination of materials, in any shape, form or size that is intended to remain in direct contact with a wound NOTE Primary wound dressings are used as mechanical barriers, for the absorption or transmission of exudates, to manage the micro-environment of the wound, and can enable the wound to heal by primary or secondary intent. Devices which have a metabolic, pharmacological or immunological interaction as their primary intent are excluded. 3 Test methods for absorbency 3.1 Test conditions Unless otherwise stated, condition the test samples and carry out the tests at a temperature of (21 ± 2) °C and a relative humidity of 60 % RH ± 15 % RH. 3.2 Free swell absorptive capacity 3.2.1 Significance and use The test is intended to assess the performance of dressings, typically used on moderately to heavily exuding wounds, where total absorptive capacity is an important feature. It is only appropriate for dressings which will stay physically intact and which will reach their maximum absorptive capacity within 30 min, under the test conditions. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 08:52:15 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13726-1:2002 (E) 6 NOTE The test is suitable for use with, for example, most types of alginate dressings in either the sheet or rope (packing) form. In the case of alginate dressings, the ratio of test liquid to sample weight is an important factor due to the interaction which takes place. 3.2.2 Equipment 3.2.2.1Petri dishes, (90 ± 5) mm in diameter. 3.2.2.2Laboratory oven, with forced air circulation, capable of maintaining a temperature of (37 ? 1) °C. 3.2.2.3Test solution A, consisting of sodium chloride and calcium chloride solution containing 142 mmol of sodium ions and 2,5 mmol of calcium ions as the chloride salts. This solution has an ionic composition comparable to human serum or wound exudate. It is prepared by dissolving 8,298 g of sodium chloride and 0,368 g of calcium chloride dihydrate in deionised water and making up to 1 litre in a volumetric flask. 3.2.2.4Balance, capable of weighing 100 g with to the nearest 0,000 1 g. 3.2.3 Procedure 3.2.3.1Place a single, weighed 5 cm x 5 cm (as presented to the wound) or 0,2 g (for cavity dressing) sample in a Petri dish. 3.2.3.2Add a quantity of test solution warmed to (37 ? 1) °C corresponding to 40 times the mass of sample being examined, ? 0,5 g. 3.2.3.3Transfer to the oven and allow to stand for 30 min at (37 ? 1) °C. 3.2.3.4Using forceps suspend the sample being examined, either by one corner or by one end as appropriate, for 30 s and then weigh it. 3.2.3.5Repeat 3.2.3.1 to 3.2.3.4 with a further nine samples 3.2.4 Calculation of results Express absorptive capacity as the average mass of solution retained per 100 cm2 (as presented to the wound) or per gram of sample (for cavity dressing). 3.2.5 Test report The report shall include at least the following information: a) type of dressing, including lot number; b) any deviations from the test method; c) individual and average absorptive capacity results; d) date of test; e) identity of the person(s) who carried out the test. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 08:52:15 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13726-1:2002 (E) 7 3.3 Fluid handling capacity (absorbency plus moisture vapour transmission rate, liquid in contact) 3.3.1 Significance and use This test is intended to assess the fluid handling capacity of waterproof wound dressings typically used for more than 24 h and when absorption of exudate and management of the micro-environment are important. 3.3.2 Equipment 3.3.2.1Five clean, dry cylinders, made of corrosion-resistant material with an internal diameter of (35,7 ± 0,1) mm (cross-sectional area 10 cm2) having a flange at each end and able each to accommodate 20 ml of test solution. (An example of a cylinder that has been found to be adequate is given in Figure 1). At one end of the cylinder is an annular clamping plate with an orifice area of 10 cm2. To prevent transpiration through the edges of the dressing an impermeable tape or alternative sealant may be used in this area. At the other end of the cylinder is a solid metal plate the full diameter of the flange. A sealing ring is also advisable to ensure an effective seal against the flange. The plates at both ends are clamped in position against the flanges. 3.3.2.2Test solution A, as specified in 3.2.2.3. 3.3.2.3A calibrated pipette. 3.3.2.4Oven or incubator, having a circulating fan and capable of maintaining a temperature of (37 ± 1) °C, and being of a design to distribute the air evenly throughout the oven or incubator so as to maintain relative humidity at less than 20 % RH throughout the test. 3.3.2.5Humidity meter, capable of detecting whether or not the 20 % RH limit has been exceeded. 3.3.2.6Balance, as specified in 3.2.2.4. 3.3.3 Procedure 3.3.3.1Cut a circular sample of dressing suitable to be clamped over the test apparatus to prevent leakage. If appropriate, remove the release liner and affix to the upper flange of a cylinder with the wound contact surface facing inwards. 3.3.3.2Place the retaining ring on the outer surface of the dressing and fasten in place. 3.3.3.3Weigh the cylinder together with the base and clamps (W1). Invert the cylinder and, using a suitable pipette, add approximately 20 ml of test solution A. Fix the solid plate in position and reweigh (W2). Repeat the procedure four times so as to prepare five samples. 3.3.3.4Place the assembled cylinder in the incubator. 3.3.3.5After 24 h, remove the cylinders from the incubator, allow them to equilibrate at room temperature for 30 min and reweigh (W3). 3.3.3.6Remove the solid plate from each cylinder, gently pour out any excess fluid and leave the cylinder to drain in the inverted position for (15 ± 2) min. Reweigh the cylinder and all its associated components, including the dressing (W4). 3.3.3.7Repeat steps 3.3.3.1 to 3.3.3.6 using fresh samples for a contact time of 48 h. 3.3.4 Calculation of results 3.3.4.1Calculate the mass of moisture vapour lost through the dressing (W2-W3) and the mass of fluid absorbed by the material (W4-W1) for the 24 h and the 48 h periods. Licensed Copy: sheffieldun sheffieldun, na, Sun Oct 29 08:52:15 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 13726-1:2002 (E) 8 3.3.4.2Record the vapour lost through the dressing and the fluid absorbed by the dressing. Additionally, record the sum of the two measurements, which is the fluid handling capacity of the dressing at 24 h and 48 h. 3.3.4.3The test is invalid if the humidity levels within the oven / incubator rise to more than 20 % RH during the test period. 3.3.5 Test report The report shall include at least the following information: a) type of dressing, including lot number; b) any deviations from the test method; c) individual and average results; d) date of test; e) identity of the person(s) who carried out the test. 3.4 Fluid affinity of amorphous hydrogel dressings 3.4.1 Significance and use This test method measures the ability of hydrogel wound dressings to donate liquid to or absorb liquid from test substrates made from gelatine or agar respectively. NOTE This test method is suitable for the evaluation of the hydroaffinity of amorphous hydrogel wound dressings. 3.4.2 Equipment 3.4.2.1Ten syringes, of nominal graduated capacity 50 ml or 60 ml, having an internal diameter of (30 ± 2) mm with the nozzles cut off, and a low-profile plunger (see Figure 2). 3.4.2.2Test solution A, as specified in 3.2.2.3. 3.4.2.3Gelatin powder, (175 bloom) 3.4.2.4Agar powder, (bacteriological agar type 1)1 3.4.2.5Selection of suitable laboratory