Conducting Risk Assessments in
the Public Health Laboratory
Debra Sharpe, MPH, CCHO, RBP
President and Managing Director
Risk Definitions
• “Possibility of loss, injury, disease, or death.”
• “The chance of injury, damage or loss.
– Chance means the probability of something happening.”
• “The probability that exposure to a hazard will lead to • “The probability that exposure to a hazard will lead to a negative consequence.”
Hazard
• Something that is dangerous- an object, a chemical, an infectious agent or a situation.
• Hazards are categorized into three groups:
– PhysicalPhysicalPhysicalPhysical hazards– ChemicalChemicalChemicalChemical hazards– ChemicalChemicalChemicalChemical hazards– BiologicalBiologicalBiologicalBiological hazards
Hazard and Risk
Hazard
• Careless handling of
SHARPS (example,
hypodermic needles)
• Pouring hazardous
Risk
• Needle stick (physical) Infection from exposure (biological)
• Chemical splashing, • Pouring hazardous
chemicals while working on
the open bench
• Overloading electrical
circuits.
• Chemical splashing, possible burn and/or exposure (chemical)
• Damaging equipment, starting a fire (physical)
Risk Assessment
• An action or series of actions taken to recognize or identifyhazards and to measure the risk or probability that something will happen because of risk. In evaluating risk, the severity of the consequences is taken into account.
• The emergent science based on toxicology, epidemiology and statistics that utilizes qualitative and quantitative hazard analysis to provide the public with a reasonable estimate of analysis to provide the public with a reasonable estimate of probability of harm.
• “Not a scalpel, but a crude tool that allows you to make estimates.” Peter Preuss, US EPA
Risk Assessment
• Difficult process (expertise of many fields needed)
• Involves uncertainty
• Range provided (not a specific number)
• Estimates for society (individual risk may vary)• Estimates for society (individual risk may vary)
• “Reasonable worst-case estimate” (better to
overestimate than underestimate risk)
• Costs and benefits of proposed actions helpful
Why Perform a Risk Assessment?
• Keep investigators safe.
• Keep the research community safe.
• Protect the environment
• Effective use of resources.• Effective use of resources.
• Identify training needs.
• Planning (renovations, new construction).
• Regulatory compliance.
• Emergency planning.
Risk assessment timing and scope
• The organization shall ensure the approach to
risk assessment is defined with respect to its
scope, nature and timing so that it is proactive
rather than reactive.rather than reactive.
From the CEN Biorisk Management Standard
CWA 15793
8
Risk assessment timing and scope
• The following should trigger either a new risk assessment or review of an existing one:
– commencement of new work or changes to the programme of work including the introduction of new biological agents or alterations to work flow or volume;biological agents or alterations to work flow or volume;
– new construction / modifications to laboratories, plant and equipment or its operation;
– introduction of altered and unplanned staffing arrangements (including contractors, visitors and other non-core personnel);
9
From the CEN Biorisk Management Standard
CWA 15793
When
• Significant alterations to Standard Operating Procedures (SOPs) or working practices (e.g. disinfection / waste management methodologies, PPE provision / usage entry / exit protocols, etc.);
• When unexpected events that may have relevance for the management of biorisks are observed;management of biorisks are observed;
• When actual or potential non-conformity with internal / external rules and regulations is identified (e.g. introduction of new legislation or major accident exposure);
10
When
• When considering emergency response and
contingency planning requirements;
• As part of the existing management system review • As part of the existing management system review
process (e.g. annually or at another appropriate and
predetermined frequency)
From the CEN Biorisk Management Standard
CWA 15793
11
When
• Regular intervals-annually
• Whenever a change in research program occurs
– Move or renovation– New employee
New pathogen or reagent– New pathogen or reagent– New equipment– New technique or procedure.
4 Steps in Risk Assessment
1. Identify health hazard
2. Quantify hazard
3. Exposure assessment (from source to at risk
person)person)
4. Determine probability of disease (based on
exposure estimate and potency of agent)
Describe work activities
Identify Hazards
Determine Risks
Decide if risk
is acceptable If Yes
Proceed with
work and
monitor
14
monitor
controls
Prepare risk control
action plan
Implement control
measures
Review adequacy of plan
If No
Revise or
close
project
Biohazard Risk Assessment
• Qualitative exercise (inexact)
• General guidelines to assess/control risk:
– agent in use, volumes, concentration– proposed practices/procedures– proposed practices/procedures– proposed location– training, experience, health status of worker
Hierarchy of Controls
• Anticipation of hazard
• Recognition of hazard
• Evaluation of hazard
• Control of hazardControl of hazard
– Substitution (surrogate organisms?)– Administrative (access control , information
dissemination, communication)– Engineering controls– Work practices– Personal protective clothing/equipment
Biohazard Risk Assessment
• Use to determine appropriate combination of containment
– lab practices– safety equipment– facility design
• Primary Containment
– protects handlers and those in immediate vicinity– protects handlers and those in immediate vicinity• Secondary Containment
– protects environment and those outside the lab
Biohazard Risk Assessment Pathway
• Principal Investigator (initiates risk review)
• Biosafety Officer (assists PI)
• Institutional Biosafety Committee (assists PI, reviews/approve
PI’s protocol submission)
• Assistance through• Assistance through
– published listings, guidelines (U.S. and abroad)– other experts at host institution, local public health– other institutions working with same agents– Government entities
Biohazard Risk Assessment & Risk Management
• Pathogen
– Infectious agent (viruses, bacteria, fungi, parasites)• Procedures (Protocol)
• Personnel
– Education– Education– Training– Experience
Biohazard Risk Assessment & Risk Management
• Engineering Controls
• Personal Protective Equipment
• Location
– Proposed lab or animal facility– Proposed lab or animal facility
Pathogen
• Quantity/Concentration
• Incidence in the Community
• Immunization/Treatment
• Communicability• Communicability
• Presence of Vectors
• Environmental Stability
• Data from animal experiments
• Clinical specimens
Pathogen
• Agent Risk Group Classification (CDC)
– Based upon microbiology and prior history of lab acquired infections
– See ABSA Risk Group website• Source of agent• Source of agent
• Routes of Exposure
• Infectious Dose (LD50’s for toxins)
Pathogen
• Pathogenicity
• Virulence
• Antibiotic resistance
• Mode of transmission and host range
• Availability of effective preventive measures (e.g.,
vaccines)
• Availability of effective treatment (e.g., antibiotics)
Risk Group Classifications
• Risk Group 1 (RG1); Managed at Biosafety Level 1 (BSL1)– Agents are not associated with disease in healthy adult
humans e.g. E. coli K12 strains, B. subtilis, S. cerevisiae
• Risk Group 2 (RG2); Managed at Biosafety Level 2 • Risk Group 2 (RG2); Managed at Biosafety Level 2 (BSL2)– Agents are associated with human disease of varying severity
(rarely serious) and for which preventative or therapeutic interventions are often available. e.g. Salmonella, Shigella, Vibrio, Plasmodium, Hepatitis B
Virus, Cryptococcus neoformans, E. coli 0157:H7
Risk Group Classifications
• Risk Group 3 (RG3);
– Managed at Biosafety Level 3 (BSL3)– Agents are associated with serious or lethal
human disease for which preventative or human disease for which preventative or therapeutic interventions may be available (high individual risk, low community risk).
e.g. Anthrax (Ames Strain)
Risk Group Classifications
• Risk Group 4 (RG4);
– Managed at Biosafety Level 4 (BSL4)– Agents are likely to cause serious or lethal human
disease for which preventative or therapeutic interventions are not usually available (high disease for which preventative or therapeutic interventions are not usually available (high individual risk and high community risk).
e.g. Ebola, Cercopithecine herpesvirus 1 (Herpes B or Monkey B virus)