Overview
ISO 20150:2019 specifies a quantitative challenge test method to assess antifungal activity of footwear and footwear components. The standard applies to products that claim antifungal (antimycotic) or antimicrobial properties and defines laboratory procedures to inoculate materials with selected test micro‑fungi, recover viable organisms, and calculate an antifungal activity ratio to quantify performance.
Key topics and technical requirements
- Two test methods:
- Dynamic challenge test - applicable to all material types.
- Static challenge test - recommended for single absorbent materials.
Brief descriptions and stepwise procedures are provided in Clauses 11.2 and 11.3.
- Quantitative endpoint: determination of viable micro‑fungi counts before and after incubation (time 0 h and time 24 h) and calculation of the antifungal activity ratio (see Clause 12).
- Test microorganisms: procedures include preparation of inocula for organisms such as Candida albicans and spore suspensions of filamentous micro‑fungi (Clauses 8–9).
- Sample handling: instructions for test specimens, control specimens (identical material without antifungal treatment), pre‑treatment, inoculation, neutralization and elution, incubation, and viable count determination (Clauses 10–11).
- Apparatus and conditions: lists required laboratory equipment, e.g. biological safety cabinet, incubator (28 ± 2 °C), humidity chamber (28 ± 2 °C, 85 ± 5 % RH), autoclave (121 ± 2 °C), shakers, spectrophotometer, petri dishes, etc. (Clause 6).
- Reagents and media: preparation details for malt medium, malt extract agar, physiological saline, neutralizers and buffers; emphasis on fresh, analytical‑grade reagents (Clause 7).
- Safety and competence: tests involve handling micro‑fungi and require containment techniques and trained personnel (Clause 5; CAUTION on front page).
Practical applications
- Validate antifungal claims on footwear uppers, linings, insoles and components.
- Support product development, quality control, and third‑party certification of antifungal treatments and finishes.
- Provide quantitative evidence for marketing claims, regulatory submissions or comparative assessments between treated and untreated materials.
Who should use this standard
- Footwear manufacturers and component suppliers
- Independent microbiology and textile/footwear testing laboratories
- R&D teams developing antifungal coatings, treatments or antimicrobial materials
- Regulatory and conformity assessment bodies assessing product claims
Related standards
- ISO 7218 (microbiological exam requirements)
- ISO 19952 (footwear vocabulary)
- ISO 20743 (neutralizer definition source)
- ISO 11133 (microbiological media preparation guidance)
- IEC 60068‑2‑10 (environmental testing guidance referenced for personnel)
Keywords: ISO 20150:2019, antifungal activity, footwear testing, quantitative challenge test, dynamic challenge test, static challenge test, viable micro‑fungi, antifungal activity ratio.