SIST EN ISO 20645:2005

Textile fabrics - Determination of antibacterial activity - Agar diffusion plate test (ISO 20645:2004)

ISO 20645:2004 specifies a method for the determination of the effect of antibacterial treatments applied to woven, knitted and other flat textiles. ISO 20645:2004 is applicable to testing hygienic finishes of hydrophilic, air-permeable materials or antibacterial products incorporated in the fibre. A minimum diffusion of the antibacterial treatment into the test agar is necessary with this procedure. ISO 20645:2004 is applicable to other materials, provided that it is adapted accordingly.
ISO 20645:2004 is not suitable for testing textiles treated with antibacterial treatments that react with the agar.

Textile Flächengebilde - Prüfung der antibakteriellen Wirkung - Agarplattendiffusionstest (ISO 20645:2004)

Dieses Dokument legt ein Prüfverfahren zur Bestimmung der Wirkung antibakterieller Behandlungen von
Geweben, Gewirken und anderen flachen Textilien fest.
Dieses Verfahren gilt für die Prüfung hygienischer Ausrüstungen hydrophiler luftdurchlässiger Materialien oder
antibakteriell ausgerüsteter Fasern. Zur Prüfung nach diesem Verfahren ist eine Mindestdiffusion der
antimikrobiellen Mittel in den Prüfagar erforderlich.
ANMERKUNG Die Prüfung anderer Materialien nach diesem Verfahren ist möglich, sofern es dementsprechend
angepasst wird.
Das Prüfverfahren ist nicht geeignet für die Prüfung von Textilien, deren antibakterielle Behandlungen mit dem
Agar eine Reaktion eingehen.

Etoffes - Contrôle de l'activité antibactérienne - Essai de diffusion sur plaques de géloses (ISO 20645:2004)

L'ISO 20645:2004 fixe une méthode de détermination de l'effet des traitements antibactériens appliqués aux textiles tissés, tricotés et autres textiles plats. Elle s'applique aux essais effectués sur les apprêts hygiéniques des matériaux hydrophiles perméables à l'air ou des produits antibactériens incorporés dans la fibre. Le mode opératoire nécessite une diffusion minimale de l'apprêt antibactérien dans la gélose. La présente méthode peut convenir à l'essai d'autres matériaux à condition d'être adaptée en conséquence.
L'ISO 20645:2004 n'est pas appropriée aux essais sur textiles soumis à des traitements antibactériens s'ils réagissent avec la gélose.

Ploskovne tekstilije - Določitev protibakterijskega delovanja - Preskus na plošči, prekriti z agarjem (ISO 20645:2004)

General Information

• Status: Published
• Publication Date: 28-Feb-2005
• ICS: 07.100.99 - Other standards related to microbiology
• ICS: 59.080.30 - Textile fabrics
• Technical Committee: ITEK - Textile and textile products
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Mar-2005
• Due Date: 01-Mar-2005
• Completion Date: 01-Mar-2005
• Ref Project: EN ISO 20645:2004 - Textile fabrics - Determination of antibacterial activity - Agar diffusion plate test (ISO 20645:2004)

Relations

• Parent: SIST EN ISO 11721-1:2001 - Textiles - Determination of the resistance of cellulose-containing textiles to micro-organisms - Soil burial test - Part 1: Assessment of rot-retardant finishing (ISO 11721-1:2001)
• Effective Date: 22-Dec-2008

Overview

EN ISO 20645:2004 - Textile fabrics - Determination of antibacterial activity - Agar diffusion plate test (ISO 20645:2004) specifies a standardized laboratory method to evaluate the antibacterial effect of treatments on woven, knitted and other flat textile materials. It is intended for hydrophilic, air‑permeable substrates or fibres with incorporated antibacterial agents where the active substance can diffuse into agar. The method gives qualitative (comparative) and semi‑quantitative information on antibacterial performance and is not suitable for treatments that chemically react with agar.

Key topics and requirements

• Test principle: Two‑layer agar plates (sterile lower layer, upper layer inoculated with bacteria). Test specimens are placed in contact with the inoculated surface and incubated; antibacterial activity is assessed by growth under the specimen and any surrounding inhibition zone.
• Test organisms: Prescribed strains include a gram‑positive (Staphylococcus aureus ATCC 6538 or equivalent) and one gram‑negative (Escherichia coli ATCC 11229 or Klebsiella pneumoniae ATCC 4352) from recognized culture collections.
• Specimen preparation: Circular specimens (25 ± 5 mm) - four specimens tested per material, tested on both sides; use unsterilized specimens unless otherwise stated; condition specimens in sterile Petri dishes for 12–24 h prior to testing.
• Culture media & reagents: Uses standard nutrient broths and agars (examples like Tryptic Soy Agar are cited); media compositions and sterilization procedures are specified.
• Apparatus & incubation: Standard microbiology equipment (incubator at 37 ± 1 °C, autoclave, water bath, stereomicroscope ×20); incubation 18–24 h.
• Assessment & evaluation: Measure inhibition zone (standard provides a calculation method) and examine contact zone under ×20 magnification. Results are classified (e.g., no growth, slight, moderate, heavy) and assessed against criteria for “good effect”.
• Safety: Tests use viable bacteria; trained personnel and appropriate biosafety procedures are required.

Applications and who uses this standard

• Textile manufacturers developing antimicrobial / hygienic finishes for medical textiles, sportswear, bedding, and PPE.
• Independent testing and certification laboratories performing comparative and quality control assessments.
• R&D teams validating new antibacterial treatments or concentrations.
• Purchasing/specification professionals who require standardized evidence of antibacterial performance.
• Useful for product claims verification, formulation optimization, and comparative benchmarking.

Related standards

• ISO 20645:2004 is the original ISO document implemented by CEN as EN ISO 20645:2004.
• The standard references microbiology practice standards for strain preservation (e.g., EN 12353) and requires use of strains from recognized culture collections.

Keywords: EN ISO 20645:2004, agar diffusion plate test, antibacterial activity, textile antibacterial testing, antimicrobial finishes, hygienic textiles.

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Textile Flächengebilde - Prüfung der antibakteriellen Wirkung - Agarplattendiffusionstest (ISO 20645:2004)Etoffes - Contrôle de l'activité antibactérienne - Essai de diffusion sur plaques de géloses (ISO 20645:2004)Textile fabrics - Determination of antibacterial activity - Agar diffusion plate test (ISO 20645:2004)59.080.30TkanineTextile fabrics07.100.99Drugi standardi v zvezi z mikrobiologijoOther standards related to microbiologyICS:Ta slovenski standard je istoveten z:EN ISO 20645:2004SIST EN ISO 20645:2005en01-marec-2005SIST EN ISO 20645:2005SLOVENSKI
STANDARD
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN ISO 20645December 2004ICS 59.080.30English versionTextile fabrics - Determination of antibacterial activity - Agardiffusion plate test (ISO 20645:2004)Etoffes - Contrôle de l'activité antibactérienne - Essai dediffusion sur plaques de gélose (ISO 20645:2004)Textile Flächengebilde - Prüfung der antibakteriellenWirkung - Agarplattendiffusionstest (ISO 20645:2004)This European Standard was approved by CEN on 2 September 2004.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2004 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 20645:2004: ESIST EN ISO 20645:2005

Special specimens and tests.11 Annex B (informative)
European Suppliers of ATCC.12 Bibliography.13
This method is applicable to testing hygienic finishes of hydrophilic, air-permeable materials or antibacterial products incorporated in the fibre. A minimum diffusion of the antibacterial treatment into the test agar is necessary with this procedure.
NOTE Other materials may be tested using this method, provided that it is adapted accordingly. This method is not suitable for testing textiles treated with antibacterial treatments that react with the agar. 2 Terms and definitions For the purposes of this document, the following term and definition applies. antibacterial effect inhibition of bacterial growth in favourable growing conditions 3 Safety precautions This method requires the use of bacteria and conditions that promote bacterial growth. Since the bacteria might be pathogenic the tests should be carried out by trained personnel. Appropriate safety precautions should be observed. 4 Principle Specimens of the material to be tested are placed on two-layer agar plates. The lower layer consists of a culture medium free from bacteria and the upper layer is inoculated with the selected bacteria. The textiles are tested on both sides. The level of antibacterial activity is assessed by examining the extent of bacterial growth in the contact zone between the agar and the specimen and, if present, the extent of the inhibition zone around the specimen. 5 Apparatus, reagents and culture media
5.1 Apparatus 5.1.1 Incubator , capable of maintaining a temperature of (37 ± 1)°C. 5.1.2 Autoclave, capable of operating at 121°C and 205 kPa (2,05 bar).
5.1.3 Water bath, capable of maintaining a temperature of (45 ± 2)°C. 5.1.4 Shaker, for test tubes
5.1.5 Microscope, 20 × magnification, lighting from beneath (lens 20x, stereomicroscope 20x). 5.1.6 Petri dishes, of glass or polystyrene construction and 9 cm inner diameter SIST EN ISO 20645:2005

hydrogen phosphate
2,5 g dextrose 2,5 g distilled water 1 000 ml Preparation Prepare the nutrient broth by heating the above solids in water until they are completely dissolved. Sterilize the broth at 121 °C (205 kPa) in the autoclave for 15 min. After sterilization, the pH of the broth shall be 7,3 ±
0,1 at 20 °C. 5.2.2.3
Composition of the medium for tests: trypton peptone 15 g phyton peptone 5
...