Biological agents


Biological agents are micro-organisms and their genetically modified variants. These can cause infection, allergy and intoxication. The risks depend on the nature of the work, the facilities in the laboratory and the properties of the specific biological agents. To guarantee the health and safety of staff and to protect the environment, working with biological agents is subject to strict statutory requirements.


Which agents

According to the law, biological agents include:

  • Bacteria;
  • Viruses and viroids;
  • Fungi;
  • Yeasts;
  • Endoparasites;
  • Genetically modified variants of the above organisms (GMOs).

Four risk classes

Biological agents are divided into 4 risk categories. The adverse health effects of the biological agent and the likelihood of their occurrence are taken as the measure for this classification.

Category 1
An agent that is unlikely to cause disease in humans.

Category 2
An agent that can cause illness in humans, pose a hazard to workers and is unlikely to spread among the population. There is usually effective prophylaxis or treatment.

Category 3
An agent that can cause serious illness in humans, pose a serious hazard to workers and is likely to spread among the population, but for which there usually is effective prophylaxis or treatment.

Category 4
An agent that causes serious illness in humans, poses a serious hazard to workers, is very likely to spread among the population and for which there usually is no effective prophylaxis or treatment.

Risk reduction

Exposure can occur when working purposely with biological agents, as is done in the laboratory, but also when not working purposely with them, such as in care, cleaning and transport. The transmission of pathogenic bacteria (pathogens) from patient to care provider can occur by:

  • Direct contact with infected patients or contaminated equipment;
  • Inhalation of aerosols: Through talking, coughing and sneezing, patients can produce small drops containing infectious agents;
  • Blood contact: Infections can be transmitted by needle-stick injuries, splashes of blood on damaged skin or mucous membranes, scratching or biting by patients and inhalation of blood aerosols. There is also a risk of infection through injuries from bone splinters or sharp instruments;
  • Contaminated syringes, scalpels and other sharp objects: Take care that these objects do not end up in the wrong waste bins or in the pockets of clothing, as they can cause injuries and infections;
  • Always report a needle-stick accident immediately in accordance with the internal guidelines so that a source investigation can be carried out and any prophylaxis can be started.

Interior requirements and operating instructions

The interior requirements and operating instructions for working with biological agents are linked to the risk class of the micro-organism. These are the management levels that can be found in the Working Conditions Decree.

The interior requirements and operating instructions for working with GMOs:

  • These are laid down in the GMO Regulations of the Ministry of Infrastructure and the Environment. They are linked to the containment level (type of microbiological laboratory ML-I to ML-IV) at which the work is to be carried out. The Ministry of Infrastructure and the Environment's GMO permit indicates the containment level for the work. Additional requirements may be imposed on the interior of laboratories. There are many similarities between the management levels for biological agents and the containment levels for GMOs;
  • The municipality, the environmental department or the province must have issued a permit under the Environmental Management Act for all areas where work with GMOs is carried out. Without internal consent, working with GMOs is not permitted. Ask the Biological Safety Officer (BSO) for the guidelines.


One way to avoid specific risks is vaccination, to which the following applies:

  • Vaccination is intended to complement and never replace other measures.
  • The executive board, as the employer, is obliged to offer vaccination against hepatitis B to staff in the high-risk groups.
  • High-risk groups are staff who run the risk of coming into contact with contaminated human material. In addition to doctors and nurses, these include paramedics, laboratory staff and transport, cleaning and other facility staff.
  • Vaccination takes place at the request of or following consent from the staff involved.

Schooling and information

All staff who are directly or indirectly involved in work with (pathogenic) biological agents must have received appropriate training and information. The following minimum requirements apply:

  • Make sure they are trained in the application of safe microbiological techniques and have knowledge of the biological agents used. They will then be familiar with the potential risks of biological agents and be able to assess their significance.
  • Make sure they are trained in the proper use of containment facilities, such as safety cabinets;
  • When providing information on working with biological agents, ensure that at least the following aspects are considered:
    - The potential health hazards;
    - The precautions to prevent exposure;
    - The actions to be taken in the event of an incident;
    - The existing hygiene regulations;
    - The wearing of work clothing and personal protective equipment.

It is important to supplement or update the information regularly in the light of developments in the field of biological agents.

Occupational health examination

For certain microorganisms, such as mycobacterium tuberculosis, it is possible to detect infections through an occupational health examination. Talk to your OHS advisor about this.


Mandatory registrations

Some registrations are required for working with biological agents. The mandatory notifications can be given to the Health and Safety Inspectorate using the registration system.

Presence of biological agents
It is mandatory to keep a register of category 2, 3 and 4 biological agents to which staff may be exposed, stating:

  • The type and classification of the agent (risk class);
  • Information on the diseases and symptoms that staff may experience when exposed to these agents.

High-risk group
You also keep a register of staff who purposely work with category 3 and 4 biological agents. This register is available for inspection by the OHS advisor. It is to be kept for at least 10 years following the last exposure. In the case of the possibility of certain infections (persistent, latent, long incubation, recurrent, with serious complications), the retention period is 40 years after the last exposure. The register contains records of:

  • The personal data of the employee;
  • The type of work performed;
  • Which biological agents may have been exposed to;
  • The exposure period.

GMO projects
In addition, you are required to keep a register of all GMO projects, which should include:

  • The permit (decision of the Ministry of Infrastructure and the Environment/GMO Agency);
  • Responsible member of staff;
  • List of project staff;
  • List of rooms where the project is to be carried out;
  • Operating procedures, other than those specified in the GMO Regulation;
  • Floor plans of laboratory and test animal housing and associated containment levels (ML-I, ML-II, ML-III, DM-I, DM-II, DM-III and D-I);
  • Storage locations outside the laboratories and storage registration per storage facility.

Biological safety officer (BSO)

If GMOs are to be used, the executive board, as the employer and permit holder, is required to appoint a biological safety officer. This officer supervises internal compliance with the permit requirements.

The Health and Safety Inspectorate is the external inspection authority when it comes to working with biological agents. This inspectorate prescribes the following rules:

  • Report 30 days prior to commencement of the work when working with biological agents class 2 and above for the first time. Report again every time you work with a new organism from category 3 and 4. You do not have to report working with a new organism of class 2.
  • Before commencing work with GMOs, provide a copy of the permit issued by the Minister for Infrastructure and the Environment.
  • Microbiological diagnostic laboratories only need to report once that they are going to work with biological agents.

More information
For more questions about working with biological agents, please contact the OHS advisor, the hospital hygienist or the biological safety officer (BSO). For more information about working with GMOs, please contact your biological safety officer.