AATCC 174-1998(2007)地毯抗微生物活性的评定(英文)

Copyright © 2006 American Association of Textile Chemists and Colorists 312TM 174-1998AATCC Technical Manual/2007Developed in 1991 by Committee RA31;revised 1992; editorially revised and re-affirmed 1993; reaffirmed 1998; editori-ally revised 2004.1. Purpose and Scope1.1 This test method is designed to determine the antimicrobial activity of new carpet materials and consists of three procedures:1.1.1 A qualitative antibacterial assess-ment.1.1.2 A quantitative antibacterial assess-ment.1.1.3 A qualitative antifungal assess-ment.1.2 This test method may also be used to evaluate the effect of a cleaning process (agreed upon by the interested parties) on the antimicrobial resistance of carpets.2. Principle2.1 This test method consists of three procedures, the principles of which are given in Sections 6, 14 and 22.3. Terminology3.1 activity, n.—of an antimicrobial agent , a measure of effectiveness of the agent.3.2 antibacterial agent, n.—any chem-ical which kills bacteria (bactericide) or interferes with the multiplication, growth or activity of bacteria (bacteriostat).3.3 antifungal agent, n.—any chemi-cal which kills or inhibits the growth of fungi.3.4 antimicrobial agent, n.—any chemical which kills or inhibits thegrowth of microorganisms.3.5 bacterial resistance, n.—in tex-tiles , resistance to the development of visible bacterial growth and accompany-ing odors, resulting from bacterial degra-dation of fibers or soil on them, as distin-guished from musty fungal odors.3.6 mildew resistance, n.—in textiles ,resistance to the development of un-sightly fungal growths and accompany-ing unpleasant, musty odors on carpet materials exposed to conditions favoring such growths.3.7 rot resistance, n.—in textiles , re-sistance to deterioration of a carpet mate-rial as a result of fungal growth in or on it.3.8 zone of inhibition, n.—clear area of no growth of a microorganism, cul-tured onto the surface of agar growth medium, in proximity to the borders of a specimen placed in direct contact withthis agar surface.NOTE: A zone of inhibition occurs as result of the diffusion of an antimicrobial agent from the specimen.4. Safety PrecautionsNOTE: These safety precautions are for information purposes only. The pre-cautions are ancillary to the testing proce-dures and are not intended to be all inclu-sive. It is the user’s responsibility to use safe and proper techniques in handling materials in this test method. Manufac-turers MUST be consulted for specific details such as material safety data sheets and other manufacturer’s recommenda-tions. All OSHA standards and rules must also be consulted and followed.4.1 This test should be performed only by trained personnel. The U.S. Depart-ment of Health and Human Services pub-lication Biosafety in Microbiological and Biomedical Laboratories should be con-sulted (see 27.1).4.2 CAUTION: Some of the microor-ganisms used in these tests are allergenic and pathogenic; i.e., capable of infecting humans and producing disease. There-fore, every necessary and reasonable pre-caution must be taken to eliminate this risk to the laboratory personnel and to personnel in the associated environment.Wear protective clothing, respiratory pro-tection, and impervious gloves when working with the organisms. NOTE:Choose respiratory protection that pre-vents penetration by the spores.4.3 Good laboratory practices should be followed. Wear safety glasses in all laboratory areas.4.4 All chemicals should be handled with care.4.5 An eyewash/safety shower should be located nearby for emergency use.4.6 Sterilize all contaminated samples and test materials prior to disposal.4.7 Exposure to chemicals used in this procedure must be controlled at or below levels set by government authorities (e.g.,Occupational Safety and Health Admin-istration’s [OSHA] permissible exposure limits [PEL] as found in 29 CFR 1910.1000 of January 1, 1989). In addi-tion, the American Conference of Gov-ernmental Industrial Hygienists (ACGIH)Threshold Limit Values (TLVs) com-prised of time weighted averages (TLV-TWA), short term exposure limits (TLV-STEL) and ceiling limits (TLV-C) are recommended as a general guide for air contaminant exposure which should be met (see 27.2).5. Uses and Limitations5.1 This test method is designed for use only for new carpets and must not be used for carpets that have been laid down and worn.I. Qualitative Assessment of Antibacterial Activity on Carpets:Single Streak Method 6. Principle6.1 Specimens of the test material,including corresponding untreated con-trols of the same material (if available but not required), are placed in intimate con-tact with nutrient agar which has been previously streaked with a bacterial cul-ture. After incubation, a clear area of interrupted growth underneath and along the sides of the test material indicates antibacterial activity of the specimen.Standard strains of bacteria are used with Staphylococcus aureus (Gram positive)and Klebsiella pneumoniae (Gram nega-tive), the representative organisms.7. Test Organisms7.1 Staphylococcus aureus , American Type Culture Collection No. 6538 (see 27.3).7.2 Klebsiella pneumoniae , American Type Culture Collection No. 4352 (see 27.3).8. Culture Medium8.1 Suitable broth/agar media are Nu-trient, Trypticase Soy and Brain-Heart In-fusion (BHI).8.2 Nutrient Broth Beef Extract 3 g Peptone 5 g Distilled water to 1000 mL 8.3 Heat to a boil to disperse ingredi-ents. Adjust to pH 6.8 with 1N sodium hydroxide (NaOH) solution. (This is not necessary if prepared, dehydrated me-dium is used.)8.4 Dispense in 10 mL amounts in con-ventional bacteriological culture tubes (i.e., 125 × 17 mm) plug and sterilize at 103 kPa (15 psi) for 15 min.8.5 Nutrient Agar (see 27.4). Add 1.5% bacteriological agar to nutrient broth. Heat to boiling. Check pH and ad-just to 7.0-7.2 using NaOH solution if necessary. Dispense in 15 mL amounts in conventional bacteriological culture tubes, plug and sterilize at 103 kPa (15psi) for 15 min.AATCC Test Method 174-1998Antimicrobial Activity Assessment of CarpetsCopyright The American Association of Textile Chemists and ColoristsProvided by IHS under license with AATCCLicensee=Hong Kong Polytechnic Univ/9976803100Not for Resale, 03/24/2007 04:07:53 MDTNo reproduction or networking permitted without license from IHS--`````,``````,,``,`,,,```,,``-`-`,,`,,`,`,,`---标准 下载Copyright © 2006 American Association of Textile Chemists and Colorists AATCC Technical Manual/2007TM 174-19983139.Maintenance of Culture of TestOrganisms9.1 Using a 4 mm inoculating loop,transfer the culture daily in nutrient broth for not more than two weeks. At the con-clusion of two weeks, make a fresh trans-plant from stock culture. Incubate cul-tures at 37 ± 2°C (99 ± 3°F).9.2 Maintain stock cultures on nutrient agar slants. Store at 5 ± 1°C (41 ± 2°F)and transfer once a month to fresh agar (see 27.5).10. Test Specimens10.1 Test specimens (non-sterile) are cut by hand or with a die. They may be any convenient size although oblong spec-imens cut 25 × 50 mm are recommended.10.2 If possible, test a specimen of the same material treated in exactly the same way with whatever other finishing agents were used, but without the antibacterial agent. However, this is not essential for the validity of the test. Many standard fin-ishing chemicals will give strong antibac-terial activity even after many cleanings.11. Procedure11.1 If durability data are desired, car-pet specimens must be tested before and after being cleaned by a test method agreed upon by the interested parties.11.2 Dispense sterilized nutrient agar cooled to 45 ± 2°C (113 ± 4°F) by pour-ing 15.0 ± 2.0 mL into each 100.0 mm di-ameter flat bottomed Petri dish. Allow agar to gel firmly before inoculating.11.3 Prepare inoculum by transferring 1.0 ± 0.1 mL of a 24 h broth culture into 9.0 ± 0.1 mL of sterile distilled water contained in a test tube or small flask.Mix well using appropriate agitation.11.4 Using a 4 mm inoculating loop,load one loopful of the diluted inoculum and transfer it to the surface of the sterile agar plate by making one long streak of approximately 75 mm in length across the center of the plate. Do not break the sur-face of the agar while making the streak.11.5 Gently press the test specimen transversely across the inoculum streak to ensure intimate contact with the agar sur-face. An easy technique is to press the specimen to the agar surface with a biolog-ical section lifter or with a spatula which has been sterilized in a flame and then air-cooled immediately before use. Test both the pile (face fibers) and the backing of the carpet on separate agar plates.11.6 Incubate the plates at 37 ± 2°C (99± 3°F) for 18-24 h.12. Evaluation and Report12.1 Examine the incubated plates for interruption of growth along the streak of inoculum beneath the specimen and for a clear zone of inhibition beyond the speci-men edge. The width of the zone of inhi-bition around the test specimen may be calculated using the following equation:W = (T – D )/2where:W =width of clear zone of inhibitionin mmT =total diameter of test specimenand clear zone in mmD =diameter of the test specimen inmm12.2 The criterion for passing the test must be agreed upon by the interested parties. To constitute acceptable antibac-terial activity, there must be no bacterial colonies directly under the sample in the contact area.12.3 Report the results of testing the carpet both before and after cleaning. The number of cleanings is to be agreed upon by the interested parties.12.4 The size of the zone cannot be construed as a quantitative evaluation of antibacterial activity. The report of results will include an observation of zones of inhibition and growth under the specimen if present.13. Precision and Bias13.1 A precision and bias statement is not applicable because data are not gener-ated by this method.II. Quantitative Assessment of Antibacterial Activity on Carpets 14. Principle14.1 This test method provides a quan-titative procedure for the evaluation of the degree of antibacterial activity.14.2 Test carpets are inoculated with the test organisms. After incubation, the bacteria are eluted from the swatches by shaking in known amounts of liquid. The number of bacteria present in this liquid is determined, and the percent reduction by the specimen is calculated (see 27.7).15. Test Organisms15.1 See Section 7.16. Culture Medium16.1 See Section 8.17.Maintenance of Culture of TestOrganisms17.1 See Section 9.18. Test Specimens18.1 Cut a circular disc of approxi-mately 48 mm in diameter from the test carpet (preferably with a steel die). Place the disc in a 250 mL wide-mouth glass jar with screw cap. The carpet disc should lie flat at the bottom of the jar.18.1.1 An uninoculated treated carpet may be used to determine the level of background organisms present on the car-pet.18.1.2 Do not sterilize carpet samples prior to testing. Sections 18.1.1 and 20.3address any problems that might arise due to the presence of background organ-isms on the carpet.19. Procedure19.1 If durability data are required, test carpet specimens before and after being cleaned in accordance with a method agreed upon by the interested parties.19.2 Apply 0.1-0.5 mL of an 18-24 h broth bacterial inoculum adjusted to 1-2× 105 CFU on the prewetted carpet fibers.The dilution of the test organism may be prepared in sterile 0.85% saline solution or suitable buffer if a steady-state culture is needed during the contact period. If,however, this test is to be performed un-der in-use conditions, use nutrient broth as the dilution medium. The carpet disc may be prewetted by dipping it in sterile deionized water or in water containing 0.05% of a non-bacteriocidal wetting agent (see 27.6) and then briefly blotting it on filter paper.19.3 Inoculate the carpet fibers evenly using a sterile pipette and place the speci-men in a glass jar. Screw the jar top on tightly to prevent evaporation.19.4 As soon as possible after inocula-tion (0 contact time), add 100 ± 0.1 mL of neutralizer solution to the jar (see 27.9).19.5 Shake the jar, either mechanically or by hand, vigorously for 1 min. Make serial dilutions and plate (in duplicate) on nutrient (or appropriate) agar. Dilutions of 100, 101 and 102 are usually suitable.19.6 The neutralizer solution should include ingredients to neutralize the spe-cific antibacterial carpet treatment and to adjust the pH to 6-8. Report the neutral-izer used.19.7 Incubation over contact periods. In-cubate additional jars containing inoc-ulated carpet discs at 37 ± 2°C (99 ± 3°F)for 6-24 h. Similar jars may be incubated over other periods (i.e., 1 or 6 h) to provide information about the bacteriocidal activ-ity of the treatment over such periods.19.8 Sampling of inoculated and incu-bated swatches. After incubation, add 100 ± 0.1 mL of neutralizer solution to jars containing treated carpet discs.Shake the jars vigorously for 1 min.Make serial dilutions and plate (in dupli-cate) on nutrient (or appropriate) agar.Dilutions of 100, 101 and 102 are usually suitable for treated test specimens. Sev-eral different dilutions may be required for untreated control carpets depending on the incubation period.19.9 Incubate all plates for 24 h at 37 ±2°C (99 ± 3°F).Copyright The American Association of Textile Chemists and Colorists Provided by IHS under license with AATCCLicensee=Hong Kong Polytechnic Univ/9976803100Not for Resale, 03/24/2007 04:07:53 MDTNo reproduction or networking permitted without license from IHS--`````,``````,,``,`,,,```,,``-`-`,,`,,`,`,,`---标准 下载Copyright © 2006 American Association of Textile Chemists and Colorists 314TM 174-1998AATCC Technical Manual/200720. Evaluation20.1 Report bacterial counts as the number of bacteria per specimen not asthe number of bacteria per mL of neutral-izer solution. Report 0 counts at 100 dilu-tion as “less than 100.”20.2 Calculate percent reduction of bacteria by the specimen treatments by one of the following formulas:1)100(B – A )/B = R 2)100(C – A )/C = R 3)100(D – A /D ) = R where:A =the number of bacteria recoveredfrom the inoculated treated test carpet in the jar incubated over the desired contact period.B =the number of bacteria recovered from the inoculated treated test carpet in the jar immediately af-ter inoculation (at 0 contact time).C =the number of bacteria recoveredfrom the inoculated untreated control carpet in the jar immedi-ately after inoculation (at 0 con-tact time). If B and C are not sim-ilar, the larger number should be used. If B and C are not signifi-cantly different, (B + C )/2 should be used.D = (B + C )/2R =% reduction20.3 If an untreated control for carpet is not available, use the following calcula-tion which allows for any background or-ganisms that might interfere with the test:Bg = 100 {(B – E ) – (A – F )/B – E }where:A ,B =(see20.2).E =the number of bacteria initially (0contact time) recovered from the uninoculated, treated test carpet (existing background organisms).F =The number of bacteria are cov-ered from the uninoculated,prewet treated test carpet after incubation in the jar over the desired contact period (existing background organisms after contact period).Bg =background organisms20.4 The criterion for passing the test must be determined by the interested parties.20.5 Report the dilution medium used.20.6 Report the results of testing the carpet both before and after cleaning. The number of cleanings is to be determined by the interested parties.21. Precision and Bias21.1 Studies (see 27.8) indicate the fol-lowing within-laboratory precision of the Standard Plate Count (SPC) Test: (a)among-analyst variation of 18%, and (b)within-analyst variation of 8%.III. Antifungal Activity Assessment of Carpet Materials: Mildew and Rot Resistance of Carpet Materials 22. Principle22.1 The carpet is subjected to the growth of a common fungus on a nutrient agar medium.23. Test Specimens23.1 Cut 38.0 ± 1.0 mm (1.5 ± 0.04 in.)diameter discs from the sample. Other shapes and sizes can be used provided the anticipated sizes of growth-free zones are taken into consideration.24. Test Procedure24.1 If durability data are required, car-pet specimens must be tested before and after being cleaned in accordance with a method agreed upon by the interested parties.24.2 Organism: Aspergillus niger ,American Type Culture Collection No.6275 (see 27.1).24.3 Culture medium: Sabouraud dex-trose agar (see 27.2).24.4 Inoculum: Add scrapings from a slant of ripe (7-14 days) fruiting culture of Aspergillus niger grown on the Sab-ouraud dextrose agar to a sterile Erlen-meyer flask containing 50 ± 2 mL of ster-ile water and a few glass beads. Shake the flask thoroughly to bring the spores into suspension. With the aid of a hemocy-tometer or a Petroff-Hausser bacteria counter, adjust the inoculum to contain one million conidia per milliliter, using sterile distilled water.24.5 Inoculation: Distribute 1.0 ± 0.1mL of the inoculum over the surface of the agar. Prewet the carpet fibers by dip-ping the carpet disc in sterile deionized water or in water containing 0.05% of a nonionic wetting agent (see 27.6), and then briefly blotting on filter paper. Dis-tribute evenly over each disc 0.2 mL of fungal spore inoculum by means of a ster-ile pipette. Inoculate the carpet specimens with the face fibers up and also with the fibers down in separate petri dishes. Incu-bate the inoculated plates at 28 ± 1°C (82± 2°F) for seven days. Longer periods of incubation may be used to provide infor-mation about antifungal activity.25. Evaluation and Report25.1 Assess the activity of the carpet as follows:25.1.1 From the plate with the speci-men whose pile is down and whose back-ing is up, observe and measure the size of any growth-free zone (in mm) produced by the pile fibers. Also from the same plate, record fungal growth on the back-ing according to the scheme below.25.1.2 From the other plate with thespecimen whose backing is down and whose pile is uppermost, observe and measure the size of any growth-free zone (in mm) from the backing and score the fungal growth on the pile side according to the scheme given below.25.1.3 Scoring Scheme:Observed Growth on SpecimenNo growth (if present, report the size of the growth-free zone in milli-meters)Microscopic Growth (visible only under the microscope)Macroscopic Growth (visible to the eye)26. Precision and Bias26.1 A precision and bias statement is not applicable because data are not gener-ated by this method.27. Notes and References27.1 American Type Culture Collection,P.O. Box 1549, Manassas V A 20108; tel: 703/365-2700; fax: 703/365-2701.27.2 Dehydrated agar may be obtained from Difco Laboratories, 920 Henry St., De-troit MI 48201. Dehydrated agar and broth can be custom formulated, upon request, from Baltimore Biological Laboratories, 250 Schill-ing Cir., Cockeysville MD 21030.27.3 Consistent and accurate testing re-quires maintenance of a pure, uncontaminated,non-mutant test culture. Avoid contamination by using good sterile technique in plating and transferring. Avoid mutation by strict adher-ence to monthly stock transfers. Check culture purity by making streak plates periodically and observing for single species-characteristic type of colonies.27.4 Publication available from U.S. De-partment of Health and Human Services CDC/NIH-HHS Publication No. (CDC) 84-8395.27.5 Booklet available from Publications Office, ACGIH, Kemper Woods Center, 1330Kemper Meadow Dr., Cincinnati OH 45240;tel: 513/742-2020.27.6 Triton™ X-100 (Union Carbide Chemicals and Plastics Co., 39 Old Ridgebury Rd., Danbury CT 06817) has been found to be a good wetting agent. Suitable alternatives are dioctyl sodium sulfosuccinate or N-methyl-tauride derivatives.27.7 The presence of antimicrobials and/or monomers in the backing of some carpets whose face fibers have not been treated may influence the results of the antibacterial quan-titative test method. Positive and favorable re-sults from this test method are not sufficient to qualify a carpet as being antimicrobial. A U.S.EPA registered biocide must be used in some part of the carpet before an antimicrobial claim can be made.27.8 Peeler, J. T., J. W. Leslie and J. W.Messer, Replicate counting errors by analysts and bacterial colony counters. Journal of Food Protection , V ol. 45, 1982, pp238-240.27.9 The following are examples of ingre-dients and their concentrations that may be added to the culture medium to neutralize in-hibitory substances present in the sample: soy lecithin, 0.5%; and Polysorbate™ 20 and 80,4.0% (ICI Americas Inc., Concord Pike and New Murphy Rd., Wilmington DE 19897; tel:800/456-3669; fax: 302/652-8836).Copyright The American Association of Textile Chemists and Colorists Provided by IHS under license with AATCCLicensee=Hong Kong Polytechnic Univ/9976803100Not for Resale, 03/24/2007 04:07:53 MDTNo reproduction or networking permitted without license from IHS--`````,``````,,``,`,,,```,,``-`-`,,`,,`,`,,`---标准 下载。