Safe deliberate work with biological agents

This page provides guidance on the duties to protect people who deliberately work with biological agents posing a risk to human health.

What deliberate work means

Deliberate use refers to any activity where biological agents are intentionally handled, propagated, processed, or manipulated as part of planned work activity.

This is different from them being present only incidentally in the working environment – there is separate guidance on preventing incidental exposure to infections at work.

Deliberate work often occurs in types of laboratories where biological agents are handled, including for:

research, teaching, and development
human, forensic, veterinary, and environmental diagnostics
pharmaceutical production

Schedule 3 of the Control of Substances Hazardous to Health Regulation (COSHH) sets out provisions relating to work with biological agents and requires:

biological agents to be suitably classified
special control measures for laboratories, animal rooms and industrial processes are implemented to ensure agents are not transmitted to workers or released outside the containment facility
a list of workers exposed to certain biological agents is kept
notification of the use and consignment of biological agents as required

Relevant legislation

The 2 main pieces of legislation that apply to work with biological agents are the:

COSHH Regulations
Health and Safety at Work Act

You can find more guidance about the law on infections at work.

Classification of biological agents

Under the COSHH Regulations, biological agents are classified according to:

ability to cause infection
severity of disease
risk that infection may spread to the community
availability of vaccines and effective treatment

The hazard groups

The resulting 4 hazard groups are defined as follows:

Hazard Group 1: unlikely to cause human disease
Hazard Group 2: can cause human disease and may be a hazard to employees – it is unlikely to spread to the community and there is usually effective prophylaxis or treatment available
Hazard Group 3: can cause severe human disease and may be a serious hazard to employees – it may spread to the community, but there is usually effective prophylaxis or treatment available
Hazard Group 4: causes severe human disease and is a serious hazard to employees – it is likely to spread to the community and there is usually no effective prophylaxis or treatment available

Biological agents are classified in the Approved List of biological agents. The List only includes agents from Hazard Groups 2 to 4. It is not exhaustive, and unlisted agents should not automatically be categorised into Hazard Group 1. The categorisation of unlisted agents should be determined by risk assessment.

The Approved List is relevant to risk assessment for work with biological agents and the application of appropriate control measures.

Assessing risks of work with biological agents

Deliberate work with biological agents needs to undergo risk assessment. Under regulation 6 of COSHH, a risk assessment of work likely to expose any workers to biological agents should consider the approved classification of that agent.

The classification gives an indication of the inherent hazards of the agents listed, but it does not consider the specific risks associated with the activities.

It also does not cover additional risks to those who have reduced or compromised immunity or infection risks to new and expectant mothers, which the risk assessment must address.

The risk assessment should also include:

biological agents that may be present and their hazard groups (in the Approved List)
forms in which biological agents may be present
diseases caused by the agent and how it can be transmitted
activities/procedures being carried out including volumes and concentrations
the likelihood of exposure and consequent disease
control measures to be applied and how exposure will be controlled (both in terms of numbers of people exposed and the quantity of the biological agent that will be used)
whether monitoring for the presence of biological agents outside primary containment is necessary
the need for health surveillance or pre-employment screening

As indicated by the definition in COSHH, the risks of allergenicity and toxicity should be considered. Certain biological agents are recognised as respiratory sensitisers (allergenic) or known to be toxigenic and are appropriately marked on the Approved List. The risk assessment should identify whether agents pose such hazards (or any other hazards that may harm human health), apart from infection.

Containment measures and containment tables

When working with an agent in a particular hazard group, the containment level selected must match the hazard group of the agent and the risks associated with the work. Containment measures are detailed in the COSHH Regulations Schedule 3, Parts 2 and 3.

You can find the main guidance for this deliberate type of work at Containment Levels 2 and 3), and the relevant tables, in Management and operation of microbiological containment laboratories.

Some of the containment measures in Schedule 3 may be needed when nursing animal or human patients that are infected, or suspected of being infected, with the highest-risk biological agents (Hazard Group 3 or 4).

Other general guidance on containment and control measures is also available:

Specialised guidance on containment and control measures

The following sections provide examples of guidance that applies the principles expressed in COSHH to specialist topics and laboratory technologies which present higher risks to employees.

Research and development

Risks and their control during work with experimentally infected animals in the laboratory setting are considered in:

Local risk assessment requirements and commensurate laboratory containment guidance while working with different strains of influenza virus is provided in Advice on experimental working with influenza viruses of pandemic potential.

Specific requirements when working with prions and proteopathic seeds are detailed in Part 3 of the DHSC guidance on minimising transmission risk of CJD and vCJD in healthcare settings (on GOV.UK).

Human and veterinary diagnostics

Clinical samples might contain biological agents – there is relevant guidance in:

Appropriate clinical information is required to assess infection risk from patient samples in diagnostic laboratories, as explained in the safety notice on risk of exposure of laboratory staff to biological agents due to missing clinical information.

Information for veterinary practices that can be used to help assess risks and implement measures to control exposure of veterinary personnel to Brucella canis is available in Brucella canis: risks and control measures in veterinary practices.

Pharmaceutical (large-scale) production

Pharmaceutical production often requires propagation of biological agents at large volumes. The associated risks and their control is discussed in guidance on large-scale contained use of biological agents.

Incidents or accidents involving a biological agent

The control measures required by regulation 7 of COSHH should provide adequate safe systems of work for dealing with most spillages and incidents involving biological agents, such as:

cleaning up
disinfection and disposal of contaminated waste
incident recording
referral for medical advice, if required

In deliberate work with biological agents, there are circumstances where an accident or incident involving the release of an agent could cause severe disease for the worker (Hazard Group 3 and 4 biological agents). The potential to infect others could mean accident or emergency response will be needed.

The risk assessment should determine when this is required and should be proportionate to the risk. The employer should identify whether workers would need to have instant access to emergency procedures to help contain an accidental release.

Accidents and dangerous occurrences when working with biological agents must be reported under the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations (RIDDOR).

There is more guidance on reporting incidents of exposure to biological agents.

Notification and licensing

Deliberate work with Hazard Group 2, 3 and 4 agents, and consignment of Hazard Group 4 agents, must be notified using a CBA1 form to HSE to obtain clearance or consent for the work. You can find guidance on notification of use and consignment of biological agents.

GMOs and animal pathogens

Deliberate work with biological agents might also include:

genetically modified organisms (GMOs) – this needs to be notified under the Genetically Modified Organisms (Contained Use) Regulations
animal pathogens – a licence is required for this work under the Specified Animal Pathogens Order (SAPO)