Biological Risk Classifier

How to use

Search for a biological agent by name. Risk group classifications are based on the WHO Laboratory Biosafety Manual (4th ed., 2020) and EU Directive 2000/54/EC Annex III. Classification determines the minimum biosafety level (BSL) required and the containment measures that must be in place.

Search for a biological agent above to view its risk group classification and containment requirements.

Risk group classifications follow WHO Laboratory Biosafety Manual (4th edition, 2020) and EU Directive 2000/54/EC. Classifications are jurisdiction-specific and may differ between countries — always verify against your national regulatory authority (e.g. ABSA in the US, OGTR in Australia, HSE ACDP in the UK). This tool is a reference guide only; it does not replace a full institutional biosafety risk assessment.

BSL — containment level summary

The four Biosafety Levels (BSL-1 through BSL-4) define the physical and procedural containment measures required based on the risk group of the biological agents handled. Requirements are cumulative — BSL-3 includes all BSL-2 requirements plus additional measures.

BSL requirements summary

Requirement	BSL-1	BSL-2	BSL-3	BSL-4
Laboratory coats / PPE	Coat	Coat + gloves	Coat + gloves + respiratory	Full positive-pressure suit
Biosafety cabinet	Not required	Class II BSC required	Class II BSC mandatory	Class III BSC or suit + Class II
Handwashing / decontamination	Sink in lab	Sink + autoclave nearby	Autoclave in lab	Autoclave in facility; shower out
Access control	Controlled	Limited access; biohazard sign	Restricted; coded access	Maximum security; air-lock
Airflow / ventilation	Standard HVAC	Inward airflow preferred	Directional inward; HEPA exhaust	Dedicated HVAC; double HEPA; negative pressure
Separated from general building	No	No (isolated work areas)	Yes — separated zone	Yes — separate building or isolated module
Medical surveillance	Not required	Recommended	Required	Required + on-site support
Corresponding risk groups	RG 1	RG 2	RG 3	RG 4

Risk group definitions — WHO LBM 4th edition (2020)

RG	Definition	Examples
1 Low	No or low individual and community risk. Unlikely to cause human or animal disease.	Bacillus subtilis, Escherichia coli K-12, Saccharomyces cerevisiae, non-infectious plant viruses
2 Moderate	Moderate individual risk; low community risk. Can cause disease; effective treatment/prophylaxis available; limited spread risk.	Salmonella spp., Staphylococcus aureus, HIV, HBV, HCV, Influenza A, Toxoplasma gondii, Aspergillus fumigatus
3 High	High individual risk; low community risk. Serious disease; effective treatment usually available; does not ordinarily spread.	Mycobacterium tuberculosis, SARS-CoV-2, West Nile virus, Brucella spp., Coxiella burnetii, HIV (some strains), MERS-CoV
4 Very high	High individual and community risk. Serious disease; no effective treatment or prophylaxis; high risk of spread.	Ebola virus, Marburg virus, Nipah virus, variola virus (smallpox), Lassa virus, Crimean-Congo haemorrhagic fever virus

References: WHO Laboratory Biosafety Manual, 4th ed. (2020); EU Directive 2000/54/EC on the protection of workers from risks related to exposure to biological agents at work; US CDC/NIH Biosafety in Microbiological and Biomedical Laboratories (BMBL) 6th ed. (2020).