Biosafety and biosecurity are crucial aspects of protecting both workers and the surrounding environment in research and healthcare settings. Biosafety focuses on preventing accidental exposure to biological agents, such as bacteria, viruses, or toxins that can cause harm to humans, animals, or the environment. This includes implementing proper containment measures, such as biosafety cabinets, personal protective equipment, and safe handling procedures. On the other hand, biosecurity involves safeguarding biological materials from theft, loss, or intentional misuse. This may involve restricting access to certain areas, implementing security protocols, and ensuring proper disposal of hazardous materials. Note that biorisk is the likelihood or probability of an adverse event occurring (such as accidental infection or unauthorized access, loss, theft, misuse, diversion, or intentional release), which could potentially cause harm.
By adhering to strict biosafety and biosecurity protocols, laboratories can minimize the risks associated with handling biological agents, protect the health and safety of workers, and prevent the release of harmful pathogens into the environment. Training staff on proper procedures, conducting risk assessments, and maintaining a culture of safety awareness are essential components of a comprehensive biosafety and biosecurity program. Additionally, regular inspections, audits, and emergency response plans can help ensure that laboratories are prepared to handle any potential incidents effectively. Overall, prioritizing biosafety and biosecurity not only protects individuals working in the lab but also helps safeguard public health and the environment.
STANDARD OPERATING PROCEDURES
This manual provides Guidelines for Biosafety in Microbiological and Biomedical Laboratories, known as a set of general standard operating procedures (SOPs) for working with chemical and biological agents. However, since these SOPs cover broad topics, individual laboratories are required to develop their own laboratory-specific SOPs that address the unique biosafety concerns and laboratory procedures of that particular facility. For example, laboratory-specific SOPs should include guidelines for the safe handling of specific organisms, specific methods for controlling exposure, and specific protocols for decontamination and waste management. There is no standardized format for SOPs, and laboratories are encouraged to use any format that effectively conveys the necessary biosafety information, including the incorporation of visual aids such as pictures and illustrations.
BIOLOGICAL SAFETY LEVELS
There are four levels of Biological Safety Levels, each with specific protocols and safety measures in place. BSL-1 is suitable for working with well-characterized agents that pose minimal risk such as low-risk microbes that pose little to no threat of infection in healthy adults. An example of a microbe that is typically worked with at a BSL-1 is a nonpathogenic strain of E. coli.
This laboratory typically consists of research taking place on benches without the use of special contaminant equipment. A BSL-1 lab, which is not required to be isolated from surrounding facilities, houses activities that require only standard microbial practices, such as:
- Mechanical pipetting only (no mouth pipetting allowed)
- Safe sharps handling
- Avoidance of splashes or aerosols
- Daily decontamination of all work surfaces when work is complete
- Hand washing
- Prohibition of food, drink and smoking materials in lab setting
- Personal protective equipment, such as; eye protection, gloves and a lab coat or gown
- Biohazard signs
BSL-1 labs also require immediate decontamination after spills. Infection materials are also decontaminated prior to disposal, generally through the use of an autoclave.
BSL-2 involves agents that pose moderate hazards to personnel and the environment, requiring additional safety precautions. This level covers laboratories that work with agents associated with human diseases (i.e. pathogenic or infectious organisms) that pose a moderate health hazard. Examples of agents typically worked with in a BSL-2 include equine encephalitis viruses and HIV, as well as Staphylococcus aureus (staph infections).
BSL-2 laboratories maintain the same standard microbial practices as BSL-1 labs, but also includes enhanced measures due to the potential risk of the aforementioned microbes. Personnel working in BSL-2 labs are expected to take even greater care to prevent injuries such as cuts and other breaches of the skin, as well as ingestion and mucous membrane exposures.
In addition to BSL 1 expectation, the following practices are required in a BSL 2 lab setting:
- Appropriate personal protective equipment (PPE) must be worn, including lab coats and gloves. Eye protection and face shields can also be worn, as needed.
- All procedures that can cause infection from aerosols or splashes are performed within a biological safety cabinet (BSC).
- An autoclave or an alternative method of decontamination is available for proper disposal.
- The laboratory has self-closing, lockable doors.
- A sink and eyewash station should be readily available.
- Biohazard warning signs
Access to a BSL-2 lab is far more restrictive than a BSL-1 lab. Outside personnel, or those with an increased risk of contamination, are often restricted from entering when work is being conducted.
BSL-3 is for handling indigenous or exotic agents that can cause serious or potentially lethal infections through inhalation. Examples of microbes worked with in a BSL-3 includes; yellow fever, West Nile virus, and the bacteria that causes tuberculosis.
The microbes are so serious that the work is often strictly controlled and registered with the appropriate government agencies. Laboratory personnel are also under medical surveillance and could receive immunizations for microbes they work with.
Common requirements in a BSL-3 laboratory include:
- Standard personal protective equipment must be worn, and respirators might be required
- Solid-front wraparound gowns, scrub suits or coveralls are often required
- All work with microbes must be performed within an appropriate BSC
- Access hands-free sink and eyewash are available near the exit
- Sustained directional airflow to draw air into the laboratory from clean areas towards potentially contaminated areas (Exhaust air cannot be re-circulated)
- A self-closing set of locking doors with access away from general building corridors
Access to a BSL-3 laboratory is restricted and controlled at all times.
Finally, BSL-4 labs are reserved for the most dangerous pathogens that pose a high risk of aerosol-transmitted infections and often require full-body suits and strict containment measures. Two examples of such microbes include Ebola and Marburg viruses. Overall, these levels ensure that research and work with dangerous pathogens are conducted in a safe and controlled manner.
In addition to BSL-3 considerations, BSL-4 laboratories have the following containment requirements:
- Personnel are required to change clothing before entering, shower upon exiting
- Decontamination of all materials before exiting
- Personnel must wear appropriate personal protective equipment from prior BSL levels, as well as a full body, air-supplied, positive pressure suit
- A Class III biological safety cabinet.
A BSL-4 laboratory is extremely isolated—often located in a separate building or an isolated and restricted zone of the building. The laboratory also features a dedicated supply and exhaust air, as well as vacuum lines and decontamination systems.
Knowing the difference in biosafety lab levels and their corresponding safety requirements is imperative for anyone working with microbes in a lab setting.
Here are some resources that provide more information on biosafety and biosecurity guidelines in clinical laboratories:
1. Centers for Disease Control and Prevention (CDC) Biosafety Guidelines: https://www.cdc.gov/safelabs/resources-tools/biosafety-resources-and-tools.html
2. World Health Organization (WHO) Laboratory Biosafety: https://www.who.int/publications/i/item/9789240011311
3. American Biological Safety Association (ABSA) Biosafety Guidlines: https://absa.org/
4. Clinical Laboratory Improvement Amendments (CLIA) regulations: https://www.cdc.gov/clia/index.html
It is important to regularly review and update biosafety and biosecurity protocols in clinical laboratories to ensure compliance with current guidelines and regulations.