Transcript Risk Assessment - University of Arizona

Risk Assessment
Challenges, Limitations, and
Making Decisions to Save Lives
Deciding How to Protect
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WHO?
– Bystanders vs.
employees
– young vs. old
– poor vs. rich
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$ How Much?
– $10,000 per life
saved
– $1,000 per life saved
– small risk vs. no job
Risk
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Technical
– # of people that will
be injured, get ill, or
die
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Non-Technical
– Upsetting,
frightening, or
enraging
Risk Assessment: Technical
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Hazard Identification
Dose-Response
Exposure Assessment
Aggregate Risk Assessment (risk to
whole population)
Hazard Identification
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Toxicology
– animal studies
– High doses
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Epidemiology
– Uses statistics to
“factor out” multiple
variables
– large effect
– large sample size
Chance & Probability
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Demonstrates two important concepts in
epidemiology & statistics:
– Sample size
– # of variables
Risk Assessment: Technical
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Hazard Identification
Dose-Response
Exposure Assessment
Aggregate Risk Assessment (risk to
whole population)
Exposure Assessment
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Have idea of how much causes harm
Want to know exposure levels
– environmental measure X time = dose
guess
– direct measurements rarely available
Aggregate Risk Assessment
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Risk to the whole population
– Census data
– Surveys
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Individual Risk vs. Societal Risk
Aggregate Risk Assessment
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Individual
– 1 death per 100
people
– 300 people exposed
– Serious for those
300 people
– Small risk for the
whole population
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Societal
–
–
–
–
1 death per 100,000
Small individual risk
250 million exposed
Greater societal risk
(2,500 deaths/year)
Risk = Hazard + Outrage
(the non-technical side)
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Voluntary vs. Involuntary
Natural vs. Industrial
Familiar vs. Exotic
Dreaded or Not
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Source: The Reporters Environmental Handbook
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