Laboratory Activities Involving Biological Agents
Hazards:
Biological agents may be encountered in laboratories where micro-organisms are
intentionally cultured or used for teaching, research or for diagnostic purpose,
where samples or tissues of human or animal origin are handled or where
laboratory animals are kept. The hazards of exposure to biological agents are:
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Infectious disease caused by pathogenic organisms
Respiratory sensitisation or allergy to non-pathogenic organisms
Toxic effects caused by microbial toxins
Classification:
COSHH classifies biological agents into one of four hazard groups based on their
ability to infect healthy humans; the classification is based on the following
criteria:
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Whether the agent is pathogenic for humans;
Whether the agent is a hazard to employees;
Whether the agent is transmissible to the community;
Whether there is effective treatment or prophylaxis available.
The four hazard groups are defined as follows:
Hazard Definition
group
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2
3
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Unlikely to cause human disease
Can cause human disease.
May be hazard to employees
Unlikely to spread to the community
Effective treatment or prophylaxis available
Can cause severe human disease.
May be serious hazard to employees.
May spread to the community
Effective treatment or prophylaxis available.
Causes severe human disease.
Serious hazard to employees
Likely to spread to the community.
No effective treatment or prophylaxis available
Handle at
containment
level
1
2
3
4
Risk Factors:
 Work with any agent capable of causing severe human disease;
 Carrying out activities or processes which may produce aerosols;
 Handling sharp instruments or objects such as needles, scalpels, broken
glass or jagged metal which may be contaminated;
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Work with high titres of biological agents;
The propagation or culturing of biological agents especially those that are
pathogenic;
Work with agents, especially parasites, which have variable life-cycle
pathogenicity;
Work with unscreened human or animal samples or tissues from a ‘high
risk’ population or infected source;
Work with cell lines or strains that are not fully characterised, which are
derived from high risk sources or which may be contaminated with
adventitious agents;
Work with agents known to be drug resistant or which have been
genetically modified so that they are intentionally drug resistant.
Risk Control Measures:
 Avoid working with a viable pathogenic organism where possible or use
the organism of least hazard consistent with the work to done.
 Only work with biological agents in laboratories or rooms with the
containment level and measures appropriate for the hazard group of the
agent(s) involved;
 Carry out manipulations or activities likely to generate an aerosol only in
suitable microbiological safety cabinet (Class I, for operator protection or
class II, for operator and product protection as defined by BS 5726:2005 &
BS EN 12469:2000);
 Avoid the use of sharp objects or implements where possible, if
unavoidable make sure that they are put into appropriate Puncture
resistant containers for safe disposal;
 Wear disposable gloves when handling infectious or contaminated
material, eye protection and a laboratory coat or plastic apron when
carrying out tasks that may result in splashing;
 Avoid hand to mouth/eye/face contact and wash your hands after
removing gloves and before leaving the laboratory;
 Do not eat, drink or apply cosmetics in any laboratory or room where
biological agents are handled or stored;
 Do not mouth pipette or use mouth operated suction devices to transfer
culture media or other fluids;
 Decontaminate benches and other surfaces that may be contaminated at
least once a day and whenever a spill of viable material has occurred,
keep freshly made stocks of suitable disinfectant available within the
laboratory for decontamination;
 Place all infectious or contaminated waste in suitable containers for
autoclaving or in disinfectant solutions, prior to disposal as clinical waste.
 Do not remove infectious or contaminated material from the laboratory to
another area unless it is suitably packaged in a sealed and labelled
container;
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Infectious materials may be centrifuged in the open laboratory if sealed
rotor heads or buckets are used and if these are only opened in a
microbiological safety cabinet;
Immunisation and regular booster injections should be provided if
appropriate as a supplementary safety precaution for those who may be
exposed to pathogenic organisms.
Persons at Special Risk:
Those who have compromised or suppressed immunity through existing
disease or medication, those who are or may be pregnant when the foetus
may be at risk and those who have a history of asthma may be at increased
risk from respiratory sensitising agents.
Health Surveillance:
Immunity levels should be checked before or after immunisation where this is
provided as a control measure against infection. Those at special risk and
exposed to respiratory sensitising agents should have periodic clinical
examination and lung function tests.
Exclusions:
This model hazard assessment may not be suitable for work with hazard
group 3 biological agents, work with laboratory or other animals infected with
pathogenic organisms including zoonoses and work involving growth or
culturing agents at large scale (>10 litres)
Relevant Statutory Provisions and Other Guidance:
 Control of Substances Hazardous to Health (COSHH) Regulations,2002,
as amended
 COSHH Biological agents Approved Code of Practice, HSE 2005
 http://www.hse.gov.uk/coshh/index.htm
HSE COSHH home page:
 http://www.hse.gov.uk/pubns/misc208.pdf
Classification of Biological Agents 2004
 http://www.hse.gov.uk/biosafety/biological agents.pdf
Biological agents, managing the risks in laboratories & healthcare
premises.
 http://www.hsebooks.com
Management & design of microbiological containment laboratories,
ACDP & HSE 2003
 BS EN 12128: 1988, biotechnology-laboratories for research,
development & analysis-containment level of microbiological laboratories,
areas of risk, localities & physical safety requirements.
 BS EN 12738: 1999, biotechnology-laboratories for research,
development & analysis-guidance for containment of animals inoculated
with micro-organisms in experiments
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http://www.hse.gov.uk/biosafety/index.htm
HSE Infections & Genetic Modification home page.
http://www.hse.gov.uk/pubns/indg342.pdf
HSE guidance on blood borne viruses in the work place
Transmissible Spongiform Encephalopathy agents: Safe working and the
prevention of infection
TSE, safe working & prevention of infection, ACDP & SEAC, 2003
http://www.hsebooks.com
Safe working and the prevention of infection in clinical laboratories &
similar facilities, HSAC & HSE, 2003
Protection against blood-borne infections in the workplace: HIV and
hepatitis, ACDP, 1995
The safe use and disposal of sharps, British Medical Association, 1990.
BS 7320:1990 Sharps containers, British Standards Institution.
Protection against blood-borne infections in the workplace: HIV and
hepatitis, ACDP, 1995
Safe disposal of clinical waste, Health and Safety Commission
Microbiological safety cabinets: BS 5726: 2005 & BS EN 12469: 2000
Standards Institution.
Autoclaves: BS2646, BS EN 12347, HTM 2010.
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