Biological Safety Manual - Chapter 02: Biological Risk Assessment


Biological Safety Manual - Chapter 02: Biological Risk Assessment


The ongoing practice of performing biological risk assessments is at the foundation of safe laboratory operations. Risk assessment requires careful judgment and is an important responsibility for directors and principal investigators of microbiological and biomedical laboratories. Institutional leadership and oversight resources, such as Institutional Biosafety Committees (IBCs), animal care and use committees, biological safety professionals, and laboratory animal veterinarians share in this responsibility. When assessing potential risks, it is essential to broadly engage stakeholders, including laboratory and facility staff and subject matter experts, in committee reviews of work practices and discussions of data regarding laboratory-associated infections (LAIs) and other published research. The biological risk assessment process is used to identify the following:

  • hazardous characteristics of a known infectious or potentially infectious agent or material;
  • the activities that can result in a person's exposure to an agent;
  • the likelihood that such exposure will cause a LAI; and
  • the probable consequences of such an infection.

The information identified by risk assessment will provide a guide for the selection of appropriate risk mitigation strategies, including the application of Biosafety Levels (BSL) and good microbiological practices, safety equipment, and facility safeguards that can help prevent LAIs.

Laboratory directors and principal investigators should use risk assessment to alert their staff to the hazards of working with infectious agents and to the need for developing proficiency in the use of selected safe practices and containment equipment. Successful control of hazards in the laboratory also protects persons not directly associated with the laboratory, such as other occupants of the same building, and the public.

Promoting a positive culture of safety by integrating a risk management process into daily laboratory operations results in the ongoing identification of hazards and prioritization of risks and the establishment of risk mitigation protocols tailored to specific situations. To be successful, this process must be collaborative and inclusive of all stakeholders. Further, it must recognize a hierarchy of controls, beginning with the elimination or reduction of hazards, then progress to implementing the appropriate engineering and/or administrative controls to address residual risks, and, if necessary, identifying personal protective equipment (PPE) to protect the worker.1

For the purposes of this section, hazards are defined as substances or situations capable of causing adverse effects to health or safety.2 Risks occur when people interact with hazards and are a function of both the probability of adverse events and expected consequences of a potential incident.2 The product of probability and consequence estimates provide a relative value that can be used to prioritize risks. Since it is impossible to eliminate all risk, unless the associated hazard is eliminated, the risk assessment evaluates recognized risks associated with a particular hazard and reduces risk to an institutionally acceptable level through a documented process. For the biological laboratory, this process is usually qualitative with classifications from high- to low-risk. This section provides guidance on conducting a risk assessment, implementing a risk mitigation program, communicating during and after the assessment, and developing practices to support ongoing application of the risk assessment process.

Risks are best mitigated by combining and overlapping risk management practices and risk mitigation controls to offer redundant protections for the worker, community, and the environment. Working through the risk assessment process identifies best practices for manipulating biological agents, how to integrate multiple containment or protection strategies, and how to respond if something does not go as planned. When performed comprehensively, it accounts for changing methodologies, procedures, and regulations as the work evolves.

Adverse consequences, like LAIs, are more likely to occur if the risks are unidentified or underestimated. By contrast, imposition of safeguards more rigorous than needed may result in additional expense and burden for the laboratory with little enhancement of laboratory safety. However, where there is insufficient information to make a clear determination of risk, consider the need for additional safeguards until more data are available.

The Biosafety in Microbiological and Biomedical Laboratories (BMBL) is designed to assist organizations with the protection of workers in biological laboratories and associated facilities from Laboratory-associated infections. Risk assessment is the basis for the safeguards developed by the CDC, the NIH, and the microbiological and biomedical community to protect the health of laboratory workers and the public from the risks associated with the use of hazardous biological agents in laboratories. Experience shows that these established safe practices, equipment, and facility safeguards work; new knowledge and experience may justify altering these safeguards.

Table of Contents

  1. The Risk Management Process
  2. Step 1 - Identify the Hazardous Characteristics of an Agent
    1. Genetically-Modified Agent Hazards
    2. Cell Cultures
    3. Transmission Routes
    4. Agent Origin
  3. Step 2 - Identify Hazardous Characteristics of Laboratory Procedures
    1. Aerosols and Droplets
    2. Personal Protective  Equipment (PPE) and Safety Equipment Hazards
    3. Facility Control Hazards
  4. Step 3 - Biosafety Level Selection and Supplemental Precautions
  5. Step 4 - Review the Risk Assessment
  6. Step 5 - Evaluate the Efficacy of the Safety Controls and Staff Proficiency
  7. Step 6 - Verify Risk Management Strategies and Update as Necessary
  8. Risk Communication
  9. Facilitating a Culture of Safety Through Risk Assessment
  10. References

I. The Risk Management Process

The principal hazardous characteristics of an agent are: its capability to infect and cause disease in a susceptible human or animal host, its virulence as measured by the severity of disease, and the availability of preventive measures and effective treatments for the disease. The World Health Organization (WHO) has recommended an agent risk group classification for laboratory use that describes four general risk groups based on these principal characteristics and the route of transmission of the natural disease.1 The four groups address the risk to both the laboratory worker and the community. The NIH Guidelines established a comparable classification and assigned human etiological agents into four risk groups on the basis of hazard.2 The descriptions of the WHO and NIH risk group classifications are presented in Table 1. They correlate with but do not equate to BSLs. A risk assessment will determine the degree of correlation between an agent's risk group classification and BSL. See Chapter 3 of the Biological Safety Manual for a further discussion of the differences and relatedness of risk groups and biosafety levels.

II. Step 1 - Identify Hazardous Characteristics of an Agent

The first step in a risk assessment will be to identify hazardous characteristics of the selected agent and perform an assessment of the inherent risk, which is the risk in the absence of mitigating factors.

Consider the principal hazardous characteristics of the agent, which include its capability to infect and cause disease in a susceptible host, severity of disease, and the availability of preventive measures and effective treatments.

Also consider the following:

  • possible routes of transmission of infection in the laboratory;
  • infectious dose (ID);
  • stability in the environment;
  • host range;
  • whether the agent is indigenous or exotic to the local environment; and
  • the genetic characteristics of the agent.3-6

A thorough examination of the agent hazards is necessary when the intended use of an agent does not correspond with the general conditions described in the agent summary statement or when an agent summary statement is not available. In addition, it is always helpful to seek guidance from colleagues with experience in handling the agent and from biological safety professionals. Several excellent resources provide information and guidance for making an initial risk assessment, including:

  • Section VIII of BMBL provides agent summary statements for many agents that are associated with LAIs or are of increased public concern.
  • Agent summary statements also identify known and suspected routes of transmission of Laboratory-associated infections and, when available, information on infective dose, host range, agent stability in the environment, protective immunizations, and attenuated strains of the agent.
  • Safety documents from reputable sources are also valuable, such as the Pathogen Data Safety Sheets generated by the Public Health Agency of Canada (PHAC).

The NIH Guidelines for Research Involving Recombinant or Synthetic Nucleic Acid Molecules (NIH Guidelines) has incorporated an agent Risk Group (RG) classification for laboratory use that describes four general Risk Groups based on these principal characteristics and the route of transmission of the natural disease; this list is found in Appendix B of the NIH Guidelines. ABSA International also has a compendium of organisms and Risk Group assignments from several countries and organizations. Agent Risk Group assignments assist with an initial estimate of the pathogen’s risk; the assessment must be modified appropriately based on the unique risks faced by each laboratory for the specific work being done. The four groups address the risk to both the laboratory worker and the community and correlate with, but do not equate to, BSLs. Other areas that should be assessed include genetic modifications, cell culture work practices, and transmission routes, which are covered in the following subsections.

There will be situations where there is not yet sufficient information available to make a comprehensive assessment of risk. For example, the hazard of an unknown agent that may be present in a specimen may not be known until the completion of agent identification and typing procedures. In cases such as those, it is prudent to assume the specimen contains an unknown agent presenting the hazardous classification that correlates with a minimum of BSL-2 containment. Identification of agent hazards associated with newly emergent pathogens also requires judgments based on incomplete information. Epidemiologic findings are often the best sources for information in these cases. When assessing the hazards of a newly attenuated pathogen, experimental data should support a judgment that the attenuated pathogen is less hazardous than the wild-type parent pathogen before making any reduction in the containment recommended for that pathogen.

A. Genetically Modified Agent Hazardous Characteristics

The identification and assessment of hazardous characteristics of genetically modified agents involve consideration of the same factors used in risk assessment of the wild-type organism. It is particularly important to address the possibility that the genetic modification could increase or decrease an agent’s pathogenicity or affect its susceptibility to antibiotics or other effective treatments. The risk assessment can be difficult or incomplete because important information may not be available for a newly engineered agent. Several investigators have reported that they observed unanticipated enhanced virulence in recent studies with engineered agents;7-10 these observations give reasons to remain alert to the possibility that experimental alteration of virulence genes may lead to altered risk and reinforce the nature of risk assessment as a continuing process that requires updating as research progresses.

The NIH Guidelines are the key reference in assessing risk and establishing an appropriate Biosafety Level for work involving recombinant DNA molecules. Please refer to Chapter 18 of the Biosafety Manual for more information about the NIH Guidelines and the NIH Office of Science Policy (OSP).

B. Cell Cultures

Workers who handle or manipulate human or animal cells and tissues are at risk for possible exposure to potentially infectious latent and adventitious agents that may be present in those cells and tissues. This risk is illustrated by the following:

  • reactivation of herpes viruses from latency;12,13
  • the inadvertent transmission of disease to organ recipients;14,15 and
  • the persistence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) within infected individuals in the U.S. population.16

In addition, human and animal cell lines that are not well characterized or are obtained from secondary sources may introduce an infectious hazard to the laboratory. For example, the handling of nude mice inoculated with a tumor cell line unknowingly infected with lymphocytic choriomeningitis virus resulted in multiple LAIs.17 See Chapter 16 of the Biosafety Manual for additional information.

Other hazardous characteristics of an agent include the following:

  • probable routes of transmission in the laboratory;
  • infective dose;
  • stability in the environment;
  • host range; and
  • its endemic nature.

In addition, reports of LAIs are a clear indicator of hazard and often are sources of information helpful for identifying agent and procedural hazards, and the precautions for their control. The absence of a report does not indicate minimal risk. The number of infections reported for a single agent may be an indication of the frequency of use as well as risk. Reporting of LAIs by laboratory directors in scientific and medical literature is encouraged. The agent summary statements in BMBL include specific references to reports on LAIs.

C. Transmission Routes

Once the inherent risk associated with the agent is considered, the next step in the process involves addressing the possibility of transmission of the agent. The most likely routes of transmission in the laboratory are:

  1. direct skin, eye or mucosal membrane exposure to an agent;
  2. parenteral inoculation by a syringe needle or other contaminated sharp, or by bites from infected animals and arthropod vectors;
  3. ingestion of liquid suspension of an infectious agent, or by contaminated hand to mouth exposure; and
  4. inhalation of infectious aerosols.

An awareness of the routes of transmission for the natural human disease is helpful in identifying probable routes of transmission in the laboratory and the potential for any risk to public health. For example, transmission of infectious agents can occur by direct contact with discharges from respiratory mucous membranes of infected persons, which would be a clear indication that a laboratory worker is at risk of infection from mucosal membrane exposure to droplets generated while handling that agent. Additional information used to identify both natural and often noted laboratory modes of transmission can be found in the Control of Communicable Diseases Manual.3 It is important to remember that the nature and severity of disease caused by a laboratory-associated infection and the probable route of transmission of the infectious agent in the laboratory may differ from the route of transmission and severity associated with the naturally-acquired disease.18

An agent capable of transmitting disease through respiratory exposure to infectious aerosols is a serious laboratory hazard, both for the person handling the agent and for other laboratory occupants. Infective dose and agent stability are particularly important in establishing the risk of airborne transmission of disease. For example, the reports of multiple infections in laboratories associated with the use of Coxiella burnetii are explained by its low inhalation infective dose, which is estimated to be ten (10) inhaled infectious particles, and its resistance to environmental stresses that enables the agent to survive outside of a living host or culture media long enough to become an aerosol hazard.19

When work involves the use of laboratory animals, the hazardous characteristics of zoonotic agents require careful consideration when completing a risk assessment. Evidence that experimental animals can shed zoonotic agents and other infectious agents under study in saliva, urine, or feces is an important indicator of hazard. The death of a primate center laboratory worker from Macacine herpesvirus 1 (MHV-1, also known as Monkey B virus) infection following an ocular splash exposure to biologic material from a rhesus macaque emphasizes the seriousness of this hazard.20 Experiments that demonstrate transmission of disease from an infected animal to a normal animal housed in the same cage are reliable indicators of hazard. Experiments that do not demonstrate transmission, however, do not rule out the hazard. For example, experimental animals infected with Francisella tularensis, Coxiella burnetii, Coccidioides immitis, or Chlamydia psittaci - agents that have caused many LAIs - rarely infect cagemates.21

D. Agent Origin

The origin of the agent is also important when conducting a risk assessment. Non-indigenous agents are of special concern because of their potential to transmit or spread infectious diseases from foreign countries into the United States. Importation of agents of human disease requires a permit from the CDC. Importation of many agents of livestock, poultry, and other animal diseases requires a permit from the USDA’s Animal and Plant Health Inspection Service (APHIS). For additional details, see Chapter 12 of the Biological Safety Manual.

Table 1

Classification of Infectious Microorganisms by Risk Group
Risk Group Classification NIH Guidelines for Research Involving Recombinant DNA Molecules 200241 World Health Organization Laboratory Biosafety Manual 3rd Edition 200442
Risk Group 1 Agents that are not associated with disease in healthy adult humans. (No or low individual and community risk) A microorganism that is unlikely to cause human or animal disease.
Risk Group 2 Agents that are associated with human disease which is rarely serious and for which preventive or therapeutic interventions are often available. (Moderate individual risk; low community risk) A pathogen that can cause human or animal disease but is unlikely to be a serious hazard to laboratory workers, the community, livestock or the environment. Laboratory exposures may cause serious infection, but effective treatment and preventive measures are available and the risk of spread of infection is limited.
Risk Group 3 Agents that are associated with serious or lethal human disease for which preventive or therapeutic interventions may be available (high individual risk but low community risk). (High individual risk; low community risk) A pathogen that usually causes serious human or animal disease but does not ordinarily spread from one infected individual to another. Effective treatment and preventive measures are available.
Risk Group 4 Agents that are likely to cause serious or lethal human disease for which preventive or therapeutic interventions are not usually available (high individual risk and high community risk). (High individual and community risk) A pathogen that usually causes serious human or animal disease and that can be readily transmitted from one individual to another, directly or indirectly. Effective treatment and preventive measures are not usually available.3

III. Step 2 - Identify Hazardous Characteristics of Laboratory Procedures

The principal laboratory procedure hazards are agent concentration, suspension volume, equipment and procedures that generate small particle aerosols and larger airborne particles (droplets), and use of sharps. Procedures involving animals can present a number of hazards such as bites and scratches, exposure to zoonotic agents, and the handling of experimentally generated infectious aerosols.

Investigations of LAIs have identified five principal routes of laboratory transmission:

  1. parenteral inoculations with syringe needles or other contaminated sharps;
  2. spills and splashes onto skin and mucous membranes;
  3. ingestion through mouth pipetting;
  4. animal bites and scratches; and
  5. inhalation exposures to infectious aerosols.

The first four routes of laboratory transmission are easy to detect, but account for less than 20% of the LAIs reported in the 1979 retrospective review by Pike.22 Subsequent research on LAIs has confirmed that the probable sources of infection are not frequently known.23

A. Aerosols and Droplets

Aerosols are a serious hazard because they are ubiquitous in laboratory procedures, are usually undetected, and are extremely pervasive, placing the laboratory worker carrying out the procedure and other persons in the laboratory at risk of infection. There is general agreement among biosafety professionals, laboratory directors, and principal investigators who have investigated LAIs that an aerosol generated by procedures and operations is the probable source of many LAIs, particularly in cases involving workers whose only known risk factor was that they worked with an agent or in an area where that work was done.

Procedures that impart energy to a microbial suspension will produce aerosols. Potential sources of aerosols include procedures and equipment used routinely for handling and analyzing infectious agents in laboratories, such as the following:

  • pipetting;
  • blenders;
  • centrifuges;
  • sonicators;
  • vortex mixers;
  • cell sorters; and
  • matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometers.24,25

These procedures and equipment generate respirable-size particles that remain airborne for protracted periods. These particles can remain in the lungs if inhaled, or create an exposure hazard for the person performing the operation, coworkers in the laboratory, and a potential hazard for persons occupying adjacent spaces open to air flow from the laboratory. A number of investigators have determined the aerosol output of common laboratory procedures. In addition, investigators have proposed a model for estimating inhalation dosage from a laboratory aerosol source.

Parameters that characterize aerosol hazards include the following:

  • an agent's inhalation infective dose;
  • its viability in an aerosol;
  • aerosol concentration; and
  • particle size.26-28

A careful and proficient worker will minimize the generation of aerosols. For example, the hurried worker may operate a sonic homogenizer with maximum aeration, but the careful worker will consistently operate the device to ensure minimal aeration. Experiments show that the aerosol burden with maximal aeration is approximately 200 times greater than aerosol burden with minimal aeration.26 Similar results were shown for improper pipetting, which generated bubbles, versus pipetting with minimal bubble generation.

Procedures and equipment that generate respirable size particles also generate larger size droplets that settle out of the air rapidly, contaminating hands, work surface, and possibly the mucous membranes of the persons performing the procedure. An evaluation of the release of both respirable particles and droplets from laboratory operations determined that the respirable component is relatively small; in contrast, hand and surface contamination can be substantial.29 The potential risk from exposure to droplet contamination requires as much attention in a risk assessment as the respirable component of aerosols.

B. Personal Protective Equipment (PPE) and Safety Equipment Hazards

There may be hazards that require specialized PPE in addition to safety glasses, laboratory gowns, and gloves. For example, a procedure that presents a splash hazard may require the use of a mask and a face shield to provide adequate protection. Inadequate training in the proper use of PPE may reduce its effectiveness, provide a false sense of security, and could increase the risk to the laboratory worker. For example, a respirator worn incorrectly may impart a risk to the wearer independent of the agents being manipulated.

Safety equipment such as biological safety cabinets (BSCs), centrifuge safety cups, and sealed rotors are used to provide a high degree of protection for the laboratory worker from exposure to microbial aerosols and droplets. Safety equipment that is not working properly is hazardous, especially when the user is unaware of the malfunction.

The following can compromise the containment capability of a BSC:

  • poor location;
  • room air currents;
  • decreased airflow;
  • leaking filters;
  • raised sashes;
  • crowded work surfaces; and
  • poor user technique.

The safety characteristics of modern centrifuges are only effective if the equipment is operated properly.

C. Facility Control Hazards

Facility safeguards help prevent the accidental release of an agent from the laboratory. For example, one facility safeguard is directional airflow. This safeguard helps to prevent aerosol transmission from a laboratory into other areas of the building. Directional airflow is dependent on the operational integrity of the laboratory's heating, ventilation, and air conditioning (HVAC) system. HVAC systems require careful monitoring and periodic maintenance to sustain operational integrity. Loss of directional airflow compromises safe laboratory operation. BSL-4 containment facilities provide more complex safeguards that require significant expertise to design and operate.

Consideration of facility safeguards is an integral part of the risk assessments. A biological safety professional, building and facilities staff, and the IBC should help assess the facility's capability to provide appropriate protection for the planned work, and recommend changes as necessary. Risk assessment may support the need to include additional facility safeguards in the construction of new or renovation of old facilities.

IV. Step 3 - Biosafety Level Selection and Supplemental Precautions

The selection of the appropriate BSL and the selection of any additional laboratory precautions require a comprehensive understanding of the practices, safety equipment, and facility safeguards available to the lab. There will be situations where the intended use of an agent requires greater precautions than those described in the agent’s summary statement. These situations will require the careful selection of additional precautions. An obvious example would be a procedure for exposing animals to experimentally generated infectious aerosols.

It is unusual that a risk assessment would indicate a need to alter the recommended facility safeguards specified for the selected BSL. If this does occur, it is important that a biological safety professional validate this judgment before augmenting any facility secondary barrier.

While an entity’s biosafety plan is based on a risk assessment, the biosafety plan may be influenced by federal regulations and guidelines. For example, the 2017 notice published by the National Science Foundation (NSF) defines standard terms and conditions for federal research grants.30 A listing of statutory, regulatory, and executive requirements is provided in Appendix C of the updated National Policy Requirements Matrix.31 The biosafety plan required by the Federal Select Agents and Toxins regulations (9 CFR Part 121, 42 CFR Part 73) must be based on an assessment that addresses the risk of the Select Agent or Toxin given its intended use and consider, where appropriate, the NIH Guidelines.

It is also important to recognize that individuals in the laboratory may differ in their susceptibility to disease. Pre-existing conditions, medications, compromised immunity, and pregnancy or breast-feeding that may increase exposure of infants to certain agents are some of the conditions that may increase the risk of an individual for acquiring an LAI. Consultation with an occupational health care provider knowledgeable in infectious diseases is advisable in these circumstances.

Laboratory directors and principal investigators, or their designees, are responsible for ensuring that the identified controls (equipment, administrative, and PPE) have been made available and are adhered to or operating properly. For example, a BSC that is not certified represents a potentially serious hazard to the laboratory worker using it and to others in the laboratory. The director should have all equipment deficiencies corrected before starting work with an agent. Vaccination(s) may be recommended for laboratory personnel based on safety and availability; however, the protection afforded by a vaccine to an individual depends on the effectiveness of the vaccine and duration of immunity. Vaccination does not substitute for engineering and administrative risk mitigation controls.

Institutions must address risk perception by setting risk tolerance limits or performance expectations on program elements and equipment identified as critical to operations.32,33 Risk mitigation requires finding a balanced approach that includes ongoing hazard identification and review of control measures with a commitment at all levels to reduce identified risk to a level tolerable to the institution. Risk acceptance is not equal acceptance of all risks; a level of biological risk may be essential to performing research, while acceptance of an equal risk of scientific misconduct is not.

V. Step 4 - Review the Risk Assessment

Before implementation of the controls, review the risk assessment and selected safeguards with a biosafety professional, subject matter expert, and the IBC or equivalent resource. This review is strongly recommended and may be required by regulatory or funding agencies. Review of potentially high-risk protocols by the IBC should become standard practice. Adopting this step voluntarily will promote the use of safe practices in work with hazardous agents in microbiological and biomedical laboratories.

VI. Step 5 - Evaluate the Efficacy of the Safety Controls and Staff Proficiency

As part of an ongoing process, evaluate the proficiencies of staff regarding safe practices and the integrity of safety equipment. The protection of laboratory workers, other persons associated with the laboratory, and the public will depend ultimately on the laboratory workers themselves.

The laboratory director or principal investigator should ensure that laboratory workers have acquired the technical proficiency in the use of microbiological practices and safety equipment required for the safe handling of the agent and have developed good habits that sustain excellence in the performance of those practices. Staff at all skill levels need to know how to identify hazards in the laboratory and how to obtain assistance in protecting themselves and others in the laboratory.

A satisfactory evaluation of the following is an important indication that a laboratory worker is capable of working safely:

  • training;
  • experience in handling infectious agents;
  • proficiency in following good microbiological practices;
  • correct use of safety equipment;
  • consistent use of standard operating procedures (SOPs) for specific laboratory activities;
  • ability to respond to emergencies; and
  • willingness to accept responsibility for protecting oneself and others.

An assessment should identify any potential deficiencies in the knowledge, competency, and practices of the laboratory workers. Carelessness is a serious concern because it can compromise any safeguards of the laboratory and increase the risk for coworkers. Fatigue and its adverse effects on safety have been well documented.34 Training, experience, knowledge of the agent and procedure hazards, good habits, caution, attentiveness, and concern for the health of coworkers are prerequisites for laboratory staff to reduce the risks associated with work with hazardous agents. Not all workers who join a laboratory staff will have these prerequisite traits even though they may possess excellent scientific credentials. Laboratory directors or principal investigators should consider the use of competency assessment(s) to train and retrain new staff to the point where aseptic techniques and safety precautions become second nature.35-37

VII. Step 6 - Verify Risk Management Strategies and Update As Necessary

A cyclical, adaptable risk management process forms the basis for a robust culture of safety in the biological laboratory.

Revisit regularly and verify risk management strategies and determine if changes are necessary. Continue the risk management cycle, and adjust and adapt as the need arises. This includes a regular update of biosafety manuals and SOPs when changes in procedures or equipment occur.

VIII. Risk Communication

An effective culture of safety depends on the effective communication and reporting of risk indicators, including incidents and near misses, in a non-punitive manner.38 Documents communicating the fundamental elements of a safety program are an important part of this culture and form the basis of the risk assessment; this includes hazard communication to all stakeholders.39 Institutional leadership can engage workers at all levels by collaborating with institutional safety programs and committing to and supporting a safe working environment.

Institutions that work with infectious agents and toxins need an appropriate organizational and governance structure to:

  • ensure compliance with the following:
    • biosafety;
    • biocontainment;
    • laboratory biosecurity regulations and guidelines;
  • and to communicate risks.40

In particular, the principal investigator or the facility equivalent has the primary responsibility for communicating hazards and risks in the laboratory. Staff must have the ability to report issues, including incidents and near misses without fear of retaliation. Laboratory staff, IBCs or equivalent resource, biosafety professionals, Institutional Animal Care and Use Committees (IACUCs), and laboratory animal veterinarians also have responsibility for identifying biological risks associated with laboratory work and communicating institute-wide risk management practices.

A biosafety officer (BSO) and/or other safety personnel can coordinate the institution’s safety program and may assist in the development of risk communication documents, including the following:

  • incident trends and mitigations;
  • SOPs;
  • biosafety manuals;
  • hazard control plans; and
  • emergency response plans.

Risk management can identify deficiencies in laboratory worker performance or institutional policies and assists institutional leadership responsible to make the necessary changes to safety programs to address those deficiencies. Biosafety program changes that promote the building of a culture of safety are most effectively communicated across the institution using multiple communication routes to ensure that all staff are informed.

Good communication practices include the following:

  • messages from leadership;
  • risk management documents;
  • IBCs, and
  • other committee reviews, as necessary.

IX. Facilitating a Culture of Safety Through Risk Assessment

The goal of your risk assessment is to address all realistic, perceivable risks to protect personnel, the community, and the environment. Research progress, changes in personnel, and changes in regulation over time drive programmatic change and demand reconsideration of all factors, as periodically necessary. Risk assessment is an ongoing process, and all personnel have a role in its success. The challenge is to develop good habits and procedures through training and competency checks with the support of leadership. Once established, these practices will persist to further instill a culture of safety. A sound risk communication strategy is also critical for both hazard identification and successful implementation. While policies and plans are tangible assets derived from the risk assessment process, the ultimate success will be measured by whether you establish, strengthen, and sustain a culture of safety while encouraging communication about risks between management and staff to prevent accidents before they happen.

The regular review of all hazards, prioritization of risk, multidisciplinary review of priority risks, and establishment of risk mitigation measures demonstrate the institution’s commitment to a safe and secure working environment and form the cornerstone of a biosafety program. The approach to risk assessment outlined in the preceding section is not static and benefits from active participation by all relevant stakeholders. Aim for ongoing evaluation and periodic readjustments to stay aligned with the changing needs of the institution and to protect all persons from potential exposure to biological materials in laboratories and associated facilities.

X. References

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Article ID: 131877
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