GB/T 20944.2-2007 PDF EnglishUS$105.00 · In stock · Download in 9 seconds
GB/T 20944.2-2007: Textiles - Evaluation for antibacterial activity - Part 2: Absorption method Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure Status: Valid
Similar standardsGB/T 20944.2-2007: Textiles - Evaluation for antibacterial activity - Part 2: Absorption method---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/GBT20944.2-2007GB NATIONAL STANDARD OF THE PEOPLE'S REPUBLIC OF CHINA ICS 59.080.30 W 04 Textiles - Evaluation for antibacterial activity - Part 2. Absorption method Issued on. JUNE 14, 2007 Implemented on. JANUARY 01, 2008 Issued by. General Administration of Quality Supervision, Inspection and Quarantine of PRC; Standardization Administration of PRC. Table of ContentsForeword... 3 1 Scope... 4 2 Normative references... 4 3 Terms and definitions... 4 4 Safety precautions... 5 5 Principles... 5 6 Devices... 5 7 Culture medium and reagents... 6 8 Test bacteria... 8 9 Cultivation and preparation of test bacterial liquid... 9 10 Preparation of specimen... 10 11 Test procedure... 11 12 Calculation and evaluation of results... 12 13 Test report... 13ForewordGB/T 20944 "Textiles - Evaluation for antibacterial activity" includes the following three parts. - Part 1.Agar diffusion plate method; - Part 2.Absorption method; - Part 3.Shake flask method. This part is Part 2 of GB/T 20944. The test method in this part refers to the absorption method, in the international standard draft ISO/DIS 20743.2005 "Textiles - Determination of antibacterial activity of textile products". This part was proposed by China Textile Industry Association. This part shall be under the jurisdiction of the Basic Branch of the National Textile Standardization Technical Committee (SAC/TC 209/SC 1). The main drafting organizations of this part. National Cotton Textile Product Quality Supervision and Inspection Center, Shenzhen Beiyue Haiwei Chemical Co., Ltd., Beijing Jiershuang High-tech Co., Ltd., Bosideng Co., Ltd., Jiangsu AB Group Co., Ltd., Southern Testing Center of Shanghai Textile Science Research Institute, Suzhou Fiber Inspection Institute and Textile Industry Standardization Institute. The main drafters of this part. Zheng Yuying, Shang Chengjie, Zou Haiqing, Gao Dekang, Zhang Hua, Jiang Jianying, Liu Chen, Xue Zhengyuan. Textiles - Evaluation for antibacterial activity - Part 2. Absorption method1 ScopeThis part of GB/T 20944 specifies the quantitative test and evaluation method, for the determination of the antibacterial activity of textiles, by the absorption method. This part applies to various textile products, such as down, fibers, yarns, fabrics and their products. This part does not involve the evaluation of the safety of antibacterial products.2 Normative referencesThe provisions in following documents become the provisions of this part through reference in this part of GB/T 20944.For the dated references, the subsequent amendments (excluding corrections) or revisions do not apply to this part; however, parties who reach an agreement based on this part are encouraged to study if the latest versions of these documents are applicable. For undated references, the latest edition of the referenced document applies. GB/T 12490-1990 Textiles - Testing method for color fastness to domestic and commercial laundering3 Terms and definitionsThe following terms and definitions apply to this part of GB/T 20944. 3.1 Antibacterial activity The performance of product to inhibit the reproduction of bacteria. 3.2 Control fabric A 100% cotton fabric, which does not subject to any treatment, is used to verify the growth conditions of the test bacteria.4 Safety precautionsThis method requires the use of bacteria AND has the conditions to promote the reproduction of bacteria.5 PrinciplesThe specimen and the control fabric are respectively inoculated with the test bacteria solution.6 Devices6.1 Spectrophotometer. Detection wavelength 660 nm. 6.2 Constant temperature incubator. The temperature can be maintained at 37 °C ± 2 °C. 6.3 Water bath. The temperature can be maintained at 45 °C ± 2 °C. 6.4 Constant temperature speed-regulating shaker cabinet. 6.8 Glass or styrene plates. Diameter 90 mm ~ 100 mm or 55 mm ~ 60 mm. 6.9 Vortex oscillator. 6.10 Two-stage biological safety cabinet. 6.11 Test tubes, flasks and other commonly used laboratory utensils.7 Culture medium and reagentsThe reagents used in the test shall be analytically pure or suitable for microbiological tests. 7.1 Soy protein broth (TSB) 7.4 SCDLP liquid medium 7.5 Diluent8 Test bacteria8.1 Strains The following Gram-positive and one of the Gram-negative strains shall be used. 8.2 Activation of freeze-dried bacteria The freeze-dried bacteria are thawed and dispersed in 5 mL of TSB (7.1) into a suspension state. It is cultured at 37 °C ± 2 °C for 18 h ~ 24 h. 8.3 Identification The following information shall be marked for each test bacteria.9 Cultivation and preparation of test bacterial liquid9.1 Culture A Use the inoculation loop to take the preserved bacteria (8.2). Inoculate the EA (7.6) plate by the line-marking method. Incubate at 37 °C ± 2 °C for 24 h ~ 2 h. Note. The plate is stored under the condition of 5 °C ~ 10 °C AND used within 1 week. 9.3 Culture C Take 20 mL of broth NB (7.3) or TSB (7.1), into a 100 mL conical flask. Take 0.4 mL of bacterial solution from culture B (9.2) AND add it to the flask for culture. The concentration of the cultured bacteria is 107 CFU/mL. 9.4 Preparation of test bacterial solution Use water to dilute the broth NB (7.3) 20 times. Adjust the bacterial concentration of culture C (9.3) to 1 x 105 CFU/mL ~ 3 x 105 CFU/mL, which is used as the test bacterial solution.10 Preparation of specimen10.1 Sample washing If evaluating the antibacterial and washing resistance performance, take 3 small samples from each large sample (each size is 10 cm x 10 cm; cut into 2 pieces). Wash it, according to the test condition A1M in GB/T 12490-1990.Use the ECE standard detergent. 10.2 Specimen mass Select a representative specimen from each sample. Cut it to an appropriate size. Weigh 0.40 g ± 0.05 g as a specimen. Take 3 specimens for the test of antibacterial activity, AND 6 control fabrics, respectively. 10.3 Placement of specimen Place each specimen in a small glass bottle. 10.4 Sterilization of specimen Choose the sterilization method according to the fiber and treatment type of the specimen. Generally, autoclave sterilization is used.11 Test procedure11.1 Inoculation of specimen Respectively pipette accurately 0.2 mL of the test bacterial solution (9.4); inoculate it to the specimen (10.3 or 10.4) in each vial. Ensure that the bacterial solution does not stick to the wall of the vial. Apply the cap tightly. Note. In order to immerse the bacterial solution on the specimen, a test bacterial solution, which contains 0.05% non-ionic surfactant, can also be used. However, it shall be indicated in the test report. 11.2 Elution immediately after inoculation Add 20 mL of SCDLP medium (7.4), into the 3 control fabric vials (11.1), which had been inoculated with the test bacteria solution. Close the cap tightly. Use hands to shake it for 30 s (swing about 30 cm). OR otherwise use a shaker to shake 5 times (5 s each time), to wash off the bacteria. 11.3 Cultivation Culture the remaining 6 vials (3 control fabrics and 3 specimens), which had been inoculated with the test bacteria solution, at 37 °C ± 2 °C for 18 h ~ 24 h. 11.4 Elution after cultivation After culture (11.3), add 20 mL of SCDLP medium (7.4) to each vial. Close the cap tightly. Use hands to shake it for 30 s (swing about 30 cm). OR otherwise use a shaker to shake it 5 times (5 s each time), to wash off the bacteria. ......Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al. Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of English version of GB/T 20944.2-2007 be delivered?Answer: The full copy PDF of English version of GB/T 20944.2-2007 can be downloaded in 9 seconds, and it will also be emailed to you in 9 seconds (double mechanisms to ensure the delivery reliably), with PDF-invoice.Question 2: Can I share the purchased PDF of GB/T 20944.2-2007_English with my colleagues?Answer: Yes. The purchased PDF of GB/T 20944.2-2007_English will be deemed to be sold to your employer/organization who actually paid for it, including your colleagues and your employer's intranet.Question 3: Does the price include tax/VAT?Answer: Yes. Our tax invoice, downloaded/delivered in 9 seconds, includes all tax/VAT and complies with 100+ countries' tax regulations (tax exempted in 100+ countries) -- See Avoidance of Double Taxation Agreements (DTAs): List of DTAs signed between Singapore and 100+ countriesQuestion 4: Do you accept my currency other than USD?Answer: Yes. www.ChineseStandard.us -- GB/T 20944.2-2007 -- Click this link and select your country/currency to pay, the exact amount in your currency will be printed on the invoice. Full PDF will also be downloaded/emailed in 9 seconds.How to buy and download a true PDF of English version of GB/T 20944.2-2007?A step-by-step guide to download PDF of GB/T 20944.2-2007_EnglishStep 1: Visit website https://www.ChineseStandard.net (Pay in USD), or https://www.ChineseStandard.us (Pay in any currencies such as Euro, KRW, JPY, AUD).Step 2: Search keyword "GB/T 20944.2-2007". Step 3: Click "Add to Cart". If multiple PDFs are required, repeat steps 2 and 3 to add up to 12 PDFs to cart. Step 4: Select payment option (Via payment agents Stripe or PayPal). Step 5: Customize Tax Invoice -- Fill up your email etc. Step 6: Click "Checkout". Step 7: Make payment by credit card, PayPal, Google Pay etc. After the payment is completed and in 9 seconds, you will receive 2 emails attached with the purchased PDFs and PDF-invoice, respectively. Step 8: Optional -- Go to download PDF. Step 9: Optional -- Click Open/Download PDF to download PDFs and invoice. See screenshots for above steps: Steps 1~3 Steps 4~6 Step 7 Step 8 Step 9 |
