The terms at a glance.
The prefix names the target group (bacteria, fungi, viruses), the suffix the type of effect: “-static” inhibits, “-cidal” kills or inactivates. The WHO counts antibiotics, antivirals, antifungals and antiparasitics as antimicrobials.
| Term | Acts against | Type of effect | Typical test basis |
|---|---|---|---|
| antibacterial | bacteria | inhibiting or killing | ISO 22196, ISO 20743 |
| bacteriostatic | bacteria | stops multiplication | minimum inhibitory concentration (MIC) |
| bactericidal | bacteria | kills | EN 1276, EN 13697 |
| antifungal | fungi (moulds, yeasts) | inhibiting or killing | ISO 13629-2, ISO 846 |
| fungicidal · yeasticidal | fungi · yeasts only | kills | EN 1650, EN 13697 |
| antiviral | viruses on materials | reduces infectious viruses | ISO 21702, ISO 18184 |
| virucidal | viruses | inactivates | EN 14476 |
| antimicrobial | umbrella term: bacteria, fungi, viruses, parasites | depends on the proven spectrum | combination of the relevant standards |
| disinfecting | pathogens on surfaces, hands, instruments | reduces them to a defined level | standards under EN 14885 |
| antibiotic | bacteria in the body | effect of a medicine | marketing authorisation for medicines |
Inhibit or kill: bacteriostatic and bactericidal.
Bacteriostatic: multiplication stops. Once exposure ends, the bacteria grow again.
Bactericidal: the bacteria die. In the laboratory a substance counts as bactericidal if the concentration for 99.9 % kill is no more than four times the minimum inhibitory concentration (Ishak et al. 2025).
1 log = 90 % · 2 log = 99 % · 3 log = 99.9 % · 4 log = 99.99 % fewer microorganisms
Log Calculator
Literature
Three orders of magnitude: virus, bacterium, yeast.
Roughly one order of magnitude separates a virus, a bacterium and a yeast. Their structure also differs fundamentally: viruses have no metabolism of their own and multiply only inside host cells. Bacteria are cells without a nucleus. Yeasts are fungal cells with a nucleus and a cell wall that contains chitin, among other components. A substance therefore does not automatically act against all three.
Virus ~0.02–0.3 µm · e.g. influenza virus ~0.1 µm
Bacterium ~0.5–5 µm · e.g. E. coli ~1 × 2 µm
Yeast ~3–8 µm · e.g. Candida albicans ~5–6 µm
Typical ranges; individual species fall above or below. Sources: Parker et al. 2016; Milo & Phillips 2015; Klis et al. 2014.
What each standard tests.
Each standard tests a specific group of organisms on a specific material. A result therefore applies only to that combination. Test conditions and evaluation are explained on the test standards page.
Test standards explained
| Standard | Material or product | Organisms | Demonstrates |
|---|---|---|---|
| ISO 22196 / JIS Z 2801 | plastics, non-porous surfaces | bacteria | antibacterial activity R |
| ISO 21702 | plastics, non-porous surfaces | viruses | antiviral activity |
| ISO 20743 | textiles | bacteria | antibacterial activity |
| ISO 18184 | textiles | viruses | antiviral activity |
| ISO 13629-2 | textiles | fungi | antifungal activity |
| ISO 846 | plastics | fungi, bacteria | resistance to microbial attack |
| ASTM E2149 | immobilised agents, shake flask | bacteria | reduction in count |
| EN 1276 · EN 1650 | disinfectants, suspension | bacteria · fungi, yeasts | bactericidal · fungicidal, yeasticidal |
| EN 13697 | disinfectants on non-porous surfaces | bacteria, fungi | bactericidal, fungicidal |
| EN 14476 | disinfectants, suspension | viruses | virucidal; at least 4 log |
Why the distinction matters for claims.
On a treated article, a biocidal property may only be stated if it is substantiated (Article 58(3)(b) BPR). Unfair competition law also prohibits misleading claims. The term must therefore match the spectrum that was tested.
- Only bacteria tested: write “antibacterial”. “Antimicrobial” suggests that fungi or viruses are covered as well.
- Only mention activity against viruses if a viral test exists, for example to ISO 21702 or ISO 18184.
- “Disinfecting” on a treated article requires an active substance approved for product-type 2. If disinfection is the main purpose, the article itself may count as a biocidal product.
- “Antibiotic” describes medicines against infections in the body, not a property of a material.
- State “bactericidal” and log reductions only with a test report, the standard and the test conditions.
Labelling and advertising bans → Treated articles /en/insights/treated-articles/
For your product
What this means for your product.
Before testing, decide which organisms matter for your product: odour-causing bacteria in textiles, mould on seals or germs on handles. The standard and the term follow from that. Z-Chitosan is called an antimicrobial technology because the Z-Chitosan patents describe it that way. Which organisms are tested for your material is decided in the project.