Biological agent

What is a biological agent and how is it classified?

Bacteria, viruses, fungi, parasites, and prions can cause infections, allergic reactions, or toxic effects in people who handle them or are exposed to them in their work. Exposure can be deliberate, when the work involves handling the agent (laboratories, biotechnology, production), or unintentional, when the agent is present but not the focus of the work (healthcare, veterinary medicine, agriculture, waste management, water treatment, cleaning, water system maintenance, work with a risk of contact with animals or materials of human or animal origin).

Royal Decree 664/1997 classifies agents into four groups: group 1, unlikely to cause disease; group 2, likely to cause disease and pose a danger to workers, with a low probability of spreading to the community and generally available effective treatment or prophylaxis; group 3, likely to cause serious disease, with a risk of spreading and generally available treatment or prophylaxis; and group 4, causing serious disease, with a high probability of spreading and no effective treatment or prophylaxis. Annex II contains the list of classified agents, updated by ministerial orders incorporating the amendments to Directive 2000/54/EC, including the inclusion of SARS-CoV-2 in group 3.

The classification refers to the risk to healthy workers; the royal decree also requires consideration of allergic and toxic effects, especially sensitive people and specific exposure conditions.

Obligations of Royal Decree 664/1997

• Identification and evaluation (Article 4). Determine the nature, degree and duration of exposure, considering the classification of the agent, the recommendations of the health authorities, information on diseases that may be contracted, the potential effects and the additional risk for sensitive workers; periodic review and in case of changes or infections.
• Substitution and reduction (Articles 5 and 6). Replace the agent with a less hazardous one where possible; if the assessment reveals risk, apply reduction measures: limit the number of exposed persons, process design and engineering controls, collective and individual protection measures, hygiene measures, signage with the biological risk pictogram, accident response plans, waste management and safe means of collection, storage and disposal.
• Hygiene measures (Article 7). Prohibition of eating, drinking or smoking in risk areas, appropriate protective clothing, toilets and washrooms, separate storage of work and street clothes, and decontamination and washing at the employer’s expense.
• Health surveillance (Article 8). Adequate and specific surveillance before exposure, at regular intervals and when an infection or disease is detected; vaccination offered when an effective vaccine exists, with information on advantages and disadvantages, at no cost to the worker; medical records kept for a minimum of ten years, extendable to forty in exposures that may lead to long-latency infections.
• Documentation and notification (articles 9 and 10). List of workers exposed to agents of groups 3 and 4 with record of exposures and accidents, kept for at least ten years; prior notification to the labour authority of the first use of agents of groups 2, 3 or 4 and of accidents or incidents.
• Information and training (Article 12). Potential risks, precautions, hygiene provisions, use of protective clothing and equipment and measures in case of incidents; written instructions and immediate notification of accidents.
• Special provisions (articles 13 to 15 and annexes IV to VI). Health and veterinary centers, laboratories and industrial processes, with containment levels according to the risk group.

Sectors and situations of regular exposure

• Healthcare. Contact with blood and fluids, injuries from sharp objects , aerosols and infectious patients; specific regulations for the prevention of injuries from cutting and piercing instruments.
• Laboratories and biotechnology. Deliberate manipulation, containment levels 2, 3 and 4 depending on the agent.
• Agriculture, livestock and veterinary medicine. Zoonoses, allergies to organic dusts and bites.
• Waste management, purification and cleaning. Unintentional exposure to agents present in waste, wastewater and contaminated environments.
• Water installations. Legionella in hot water systems, cooling towers, and aerosol-generating equipment.
• Work involving contact with the public and travel. Communicable diseases in epidemic contexts and travel to endemic areas.

Organizational application: how to manage exposure

1. Identify tasks with deliberate or non-deliberate exposure to biological agents and determine the likely agents and their risk group.
2. Evaluate exposure by job position using the INSST technical guide, considering entry routes, frequency, quantity and especially sensitive people.
3. Apply the hierarchy of measures: substitution, containment, ventilation and engineering controls, collective protection, organization, individual protection and hygiene.
4. Organize specific health surveillance with the prevention service, including the offer of vaccination and protocols for accidental exposures.
5. Prepare and maintain the list of those exposed to agents of groups 3 and 4 and make the notifications to the labor authority.
6. Provide written training and information on risks, measures, equipment use and incident response.
7. Manage biological waste and work clothes according to established procedures.

Preventive management software allows you to maintain the inventory of agents and tasks, the list of exposed workers with their retention periods, the vaccinations offered and accepted, and the records of incidents and training.

Limits and common mistakes

1. Limiting the assessment to the healthcare and laboratory sectors, neglecting unintentional exposures in cleaning, waste, maintenance, or agriculture.
2. Confusing group classification with a measure of severity for each person; allergic and toxic effects and individual sensitivity should be assessed separately.
3. Consider that vaccination replaces containment and protection measures.
4. Failure to retain the list of exposed persons and medical records for the required periods.
5. Failing to notify the labor authority of the first-time use of agents from groups 2 to 4.
6. Using respiratory protection equipment without adapting the type of filter or mask to the agent and the task.

The list of agents and their classification is updated periodically; the current version of Annex II of Royal Decree 664/1997 and the INSST technical guide should be consulted.

Regulatory framework in Spain

• Royal Decree 664/1997, of May 12. Protection of workers against risks related to exposure to biological agents during work.
• INSST technical guide on biological agents . Criteria for the application of Royal Decree 664/1997.
• Directive 2000/54/EC of the European Parliament and of the Council of 18 September 2000. Protection of workers from the risks related to exposure to biological agents at work.
• Royal Decree 39/1997, Annex I. Exposure to biological agents of groups 3 and 4 is an activity of special danger.
• Law 31/1995, articles 22 and 25. Health surveillance and protection of particularly sensitive workers .

The ILO and WHO publish guidelines on biological risks in the workplace; in Colombia, biological risk management is integrated into the Occupational Health and Safety Management System (SG-SST) of Decree 1072 of 2015 and into health sector regulations. ISO offers non-certifiable guidelines on infectious diseases at work in ISO 45006 and, for safe work during the COVID-19 pandemic, in the ISO/PAS 45005 specification .