The HSE-gateway

Biological factors

Biological factors are microorganisms (bacteria, viruses, fungi and microscopic parasites), cell cultures, human endoparasites and components from microorganisms that can cause damage to health in humans.

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Microorganisms are found everywhere: in laboratories, industry, when dealing with patients or working with laboratory animals and fish, when travelling or sorting waste, on infected syringe needles and in the indoor climate, to name but a few places.

The vast majority are harmless and, indeed, essential; even so, many microorganisms can cause damage to health, illnesses and allergies.

This depends on:

  • the harmful properties of the microorganism
  • the quantity of microorganisms in the workplace
  • the spread of microorganisms in the workplace
  • how they enter the body
  • the individual employee’s susceptibility to the microorganism


Training should include information on which microorganisms employees may be exposed to and what damage to health may result from such exposure.

It should also include the importance of personal hygiene and cleaning of the workplace, and the use and handling of work clothing and personal protective equipment. Written procedures in the event of an accident must be drawn up and readily available. Information must be provided on measures to prevent and reduce exposure. Information must also be provided on health examinations and vaccination if a risk assessment shows that the person is exposed to biological factors.


For hazardous biological material, information sheets must be prepared containing information on name, supplier, health-damaging properties, risk of infection, risk factors, preventive measures and first aid. Optionally, you can use the Chemical Inventory, where you can create information sheets.

If the employee is or has been exposed to biological factors in infection risk groups 3 and 4, this must be registered in a register. The register must contain information about name, social security number, type of work and which biological factor. The register must be kept for at least 40 years after the exposure has ceased. Optionally, the exposure register EcoExposure can be used.


Risk assessment

A risk assessment must be carried out on all work that involves biological factors. The risk assessment should take into account:

  • exposure
  • safe storage
  • the biological factors that may be present
  • toxic/harmful substances
  • the infection risk group
  • information on illness caused by the biological factors
  • the likelihood of damage to health
  • any knowledge that a proven illness may be directly connected to the work
  • recommended precautions and safety measures
  • the possibility of theft of biological factors

Where the risk assessment shows that the employee may have been exposed to biological factors that are hazardous to health in such a way that more than the normal hygiene precautions are required; in this case, the employee must undergo a suitable health examination.

Obligation to report

Notify (by letter) the Norwegian Labour Inspection Authority (NO) not less than 30 days before the unit begins to use biological factors in infection risk groups 2, 3 and 4. The purpose of giving notice is so that the Authority knows that a risk assessment has been carried out and that there are plans to initiate measures to protect the employees.


Waste must be autoclaved and disposed of as residual waste if the waste has been rendered harmless. Otherwise, it must be sent as problematic waste. If the waste contains hazardous chemicals, it must be determined in each individual case whether it should be disposed of as hazardous waste or problem waste. The waste must be packaged thoroughly and labelled with the infection risk group.

Genetically modified microorganisms must be inactivated before disposal. Where antibiotic resistance genes are used, these must be processed such that the genes are destroyed – for example, by fragmentation.

  • Chemical disinfection (70% ethanol, chlorine, other detergents)
  • Autoclaving
  • Dry heat sterilisation (keep in heat cabinet at 190°C for 6 hours)

UV light irradiation of workbenches (NB! Ventilate the room before use.)

Wastes containing antibiotics must be treated differently depending on their stability. It is very important to prevent antibiotics from entering the environment. Easily degradable antibiotics like Ampicillin, Penicillin, Erythromycin, Tetracycline, etc. can be destroyed / inactivated by autoclaving. Other antibiotics like Kanamycin, etc. can withstand heat treatment and should be sent solely for combustion as problematic waste. If you are unsure how to dispose of the antibiotic you are using, please contact the HSE-section