Biohazard is the risk caused by microorganisms present in different substances that workers may come into contact with.
Exposure to biological agents occurs whenever a person comes into contact in the workplace, but also in neighboring environments, with natural or organic materials, or with microbiological pollution represented by occupants (humans, animals, plants), dust, structures and services, of buildings.
In addition to these sources, humidifiers and air conditioners are added.
The ways in which transmission of occupational infections occurs differ depending on the task performed, the characteristics of the work environment and the microorganisms involved.

It is possible to identify 2 different types of biohazard in occupational settings:

• Generic biohazard: present in all work environments;
• Specific biological risk: specific to the task performed, which in turn can be distinguished into:
  1. Deliberate biohazard: occurs when a particular activity involves the deliberate, intentional use of biological agents, for example, a microorganism is used in food production; in such a case, the biological agent is well known and is intentionally introduced into the work cycle to be handled, manipulated, processed or to exploit its biological properties.
  2. Potential biohazard: arises from unintentional, potential exposure to biological agents; for example, waste separation or agricultural activities.

Health risks

Biological agents can cause three types of diseases:

• Infections caused by parasites, viruses or bacteria;
• Allergies triggered by exposure to mold, organic dusts such as flour dusts, animal dusts, enzymes, and mites;
• Poisoning or toxicogenic effects.

The DVR with regard to biohazard must include:

• An indication of the phases of the work where the biohazard is present;
• The number of workers assigned to the stages where the biohazard is present;
• Name and generalities of the RSPP;
• The methods, work procedures, and preventive measures applied;
• the program to protect workers against the risks of exposure to a Group 3 or Group 4 biological agent in the case of a defect in physical containment.