Laboratory » Biological Hazards – Infectious Diseases

Workers in hospital settings may be exposed to a variety of common and emerging infectious disease hazards, particularly if proper infection prevention and control measures are not implemented in the workplace. Examples of infectious disease hazards include seasonal and pandemic influenza; norovirus; Ebola; Middle East Respiratory Syndrome (MERS), tuberculosis, methicillin-resistant Staphylococcus Aureus (MRSA), and other potentially drug-resistant organisms.

Infectious diseases are caused by agents that are transmissible through one or more different routes, including the contact, droplet, airborne, and bloodborne routes. The transmission of infectious agents through the bloodborne route—a specific subset of contact transmission—is defined in the Bloodborne Pathogens (BBP) standard, 29 CFR 1910.1030 ().

An effective infection control program normally relies upon a multi-layered and overlapping strategy of engineering, administrative and work practice controls, and PPE. It is OSHA's intent in this eTool to highlight some – not all – of the controls that would be necessary to the development and implementation of an effective program. Implementing the controls highlighted here alone will not typically protect workers from infection hazards.

Follow standard and transmission-based precautions to prevent worker infections (see also the OSHA page: Worker protections against occupational exposure to infectious diseases). Early identification and isolation of sources of infectious agents (including sick patients), proper hand hygiene, worker training, effective engineering and administrative controls, safer work practices, and appropriate personal protective equipment (PPE), among other controls, help reduce the risk of transmission of infectious agents to workers.

Employers must comply with the BBP standard to the extent that there is "occupational exposure" (i.e., to the extent workers should reasonably anticipate contact with blood or other potentially infectious materials (OPIM) that may result from the performance of duties). Employers must also comply with the PPE Standard, 29 CFR 1910 Subpart I, and the OSH Act's General Duty Clause, 29 U.S.C. 654(a)(1), to protect their workers from infectious disease hazards. The General Duty Clause requires each employer to "furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees."

OSHA provides agent-specific guidance for a variety of pathogens that workers in hospital settings may encounter. See OSHA's Safety and Health Topics Pages for Biological Agents and Bloodborne Pathogens and Needlestick Prevention for additional information.

In this module, OSHA provides additional guidance specifically for

Bloodborne pathogens are pathogenic microorganisms present in human blood that can cause disease in humans. These pathogens include, but are not limited to, Hepatitis B Virus (HBV), Hepatitis C Virus (HCV), Human Immunodeficiency Virus (HIV) and Viral Hemorrhagic Fevers (e.g. Ebola). [29 CFR 1910.1030(b)]


Laboratory workers are at particular risk for exposure to blood or other potentially infectious materials (OPIM) because of the handling of clinical specimens in the laboratory.

Requirements under OSHA's Bloodborne Pathogens Standard, 29 CFR 1910.1030

The Bloodborne Pathogens Standard requires precautions when there is occupational exposure to blood or OPIM (as defined by the standard). Under the standard, OPIM means (1) the following human body fluids: semen, vaginal secretions, cerebrospinal fluid, synovial fluid, pleural fluid, pericardial fluid, peritoneal fluid, amniotic fluid, saliva in dental procedures, any body fluid that is visibly contaminated with blood, and all body fluids in situations where it is difficult or impossible to differentiate between body fluids; (2) any unfixed tissue or organ (other than intact skin) from a human (living or dead); and (3) HIV-containing cell or tissue cultures, organ cultures, and HIV- or HBV-containing culture medium or other solutions; and blood, organs, or other tissues from experimental animals infected with HIV or HBV.

Have the laboratory director, biosafety officer, or other responsible person conduct an exposure determination to determine all tasks and procedures in the laboratory in which there is exposure to bloodborne pathogens (e.g., where there is a potential for sprays, splashes, or aerosol generated during laboratory procedures). [29 CFR 1910.1030(c)(2)(i)]

Under the Bloodborne Pathogens Standard:

  • Mouth pipetting/suctioning of blood or other potentially infectious materials is NOT allowed. [29 CFR 1910.1030(d)(2)(xii)]
  • Eating, drinking, smoking, applying cosmetics or lip balm, or handling contact lenses is NOT allowed in work areas where there is a reasonable likelihood of occupational exposure to bloodborne pathogens. [29 CFR 1910.1030(d)(2)(ix)]
  • Food and drink is NOT to be kept in refrigerators, freezers, shelves, cabinets or on countertops or bench tops where blood or other potentially infectious materials are present. [29 CFR 1910.1030(d)(2)(x)].

For more information, see Hospital-wide Hazards - Bloodborne Pathogens

Needlestick/Sharps Injuries


Exposure to blood and OPIM from needlestick injuries due to:

  • Unsafe needle devices
  • Improper handling and disposal of needles

Requirements under Bloodborne Pathogens Standard, 29 CFR 1910.1030

Additional Information

Other Sharps

Take precautions with respect to all contaminated sharps, not just needles. "Contaminated Sharps" means any contaminated object that can penetrate the skin including, but not limited to, needles, scalpels, broken glass, broken capillary tubes, and exposed ends of dental wires. [29 CFR 1910.1030(b)]


Exposure to blood and OPIM through contaminated sharps, such as:

  • I.V. Connectors that use needle systems.
  • Broken Capillary Tubes.

Follow requirements of the Bloodborne Standard (29 CFR 1910.1030) with respect to all "contaminated sharps." For example:

Additional Information

Engineering Controls

OSHA's Bloodborne Pathogens Standard requires that engineering and work practice controls be used to eliminate or minimize exposures to blood and other potentially infectious materials (OPIM). [29 CFR 1910.1030(c), 29 CFR 1910.1030(d)].

The Bloodborne Pathogens Standard requires that Universal Precautions be observed. This means that all specimens of human blood and certain human bodily fluids must be treated as if known to be infectious for bloodborne pathogens. Of course, the protections of the standard also apply if the specimens are from a patient who is known or suspected to be infectious with bloodborne pathogens, such as Ebola. Laboratories must therefore:

Image of a splatter guard
Image of a foot-operated sink
Image of a biological safety cabinet
  • Use effective engineering and safe work practice controls to minimize or eliminate exposure in connection with collecting, transporting, storing, packaging and shipping these specimens. [29 CFR 1910.1030(d)(2)]
  • Use effective engineering controls (e.g., biological safety cabinets) and safe work practice controls to minimize or eliminate exposure in connection with potential splashes of, or aerosol-generating laboratory procedures on, these specimens. [29 CFR 1910.1030(d)(2)]

Where occupational exposure remains after institution of engineering and work practice controls, personal protective equipment must also be used. [29 CFR 1910.1030(d)(2)]

The basic concept behind engineering controls is that, to the extent feasible, the work environment and the job itself should be designed to eliminate hazards or reduce exposure to hazards. Some examples are:

  • Splatter guards to prevent splashing from reaching employee, (e.g., plexiglass barriers).
  • Sensor-controlled automatic sinks or foot, knee, or elbow controls that are available on sinks to operate handwashing facilities without using hands so that the contaminants are not spread from the hands to sink handles.
  • Ventilation systems (e.g. laboratory hoods). Be sure to properly maintain ventilation systems and keep associated maintenance records.
  • Centrifuge tubes with caps.
  • Biological safety cabinets.
    • Biological Safety Cabinets (BSCs), when properly maintained and used in conjunction with good microbiological techniques, provide an effective containment system for safe manipulation of moderate- and high-risk infectious agents [Biosafety (BSL) Level 2 and 3 agents].
    • BSCs protect laboratory workers and the immediate environment from infectious aerosols generated within the cabinet. BSCs must be certified when installed, whenever they are moved and at least annually. [29 CFR 1910.1030(e)(2)(iii)(B)]

Additional Information

The CDC considers workers in medical laboratories that handle M. Tuberculosis to be at high risk for occupational transmission of TB. The potential of contracting TB among persons who work with TB in the laboratory is three times greater than among lab personnel that do not work with TB bacterium (CDC).


Exposure of laboratory employees to M. tuberculosis from working with specimens (e.g., acid fast bacilli smears), from patients who have tuberculosis. Other potential sources of exposure are sputum, cerebrospinal fluid, urine, and fluids collected from gastric or bronchial lavage.

Recognized Controls and Work Practices

All cultures or specimens known to contain, or suspected of containing, TB bacilli must be manipulated in settings where specific engineering controls, administrative procedures, appropriate personal work practices, and use of PPE ensure containment of the organism and protection of the workers. Recognized practices include:

  • Biosafety Level: For a laboratory to handle TB sputum and TB materials, the laboratory must operate at a biosafety level of 2 or 3, as specified.
  • Controlled access, anterooms, sealed windows, directional airflow, preventing recirculation of laboratory exhaust air, filtration of exhaust air before discharge to the outside, and thimble exhaust connections for biological safety.
  • The use of biological safety cabinets (BSCs) whenever working with infectious materials that have a chance of splashing or aerosolizing. Processes that can expose employees to splashes or aerosolized materials include:
    • Pouring liquid cultures
    • Using fixed-volume automatic pipettes
    • Mixing liquid cultures with a pipette
    • Preparing specimens and culture smears
    • Dropping and spilling tubes containing suspensions of bacilli
    • Centrifugation of specimens without tops
  • Ensure the use of appropriate PPE, including respiratory protection (e.g., N-95 respirator).

Additional Information


Exposure of laboratory staff to seasonal or pandemic influenza. The CDC has documented cases of laboratory-acquired influenza among laboratory staff who handle influenza specimens.

Influenza can be transmitted by both symptomatic and asymptomatic individuals through infected respiratory tract secretions, mucus, cough aerosols, and contaminated hands and materials.

Recognized Controls and Work Practices

  • Encourage workers to get vaccinated and make vaccinations available to workers. The Centers for Disease Control and Prevention (CDC), the Advisory Committee on Immunization Practices (ACIP), and the Healthcare Infection Control Practices Advisory Committee (HICPAC) recommend that all U.S. healthcare workers get vaccinated annually against influenza.
  • Use the appropriate Biosafety Level when handling specimens from flu patients (i.e., patients known to have, or suspected of having, influenza).
  • Use gloves, gowns, eye protection, and other appropriate PPE for any tasks that might cause contamination or create splashes.
  • Put on and take off protective equipment in the correct order to prevent contamination.
  • Use proper respiratory and cough etiquette and encourage hand washing by laboratory staff.
  • Follow standard cleaning and disinfection methods.

Additional Information

Seasonal Flu

Pandemic Influenza

The following resources offer information on the potential for exposure to Zika virus: