BEPP 261 Exam
Principles of Risk Communication
(from The Psychology of Climate Change Communication) Know your audience Get your audience's attention Translate Scientific Data into Concrete Data Beware of the Overuse of Emotional Appeals Address Scientific and Climate Uncertainties Tap into Social Identities and Affiliations Encourage Group Participation Make Behavior Change Easier
Decision Alaysis and Cost-Benefit: Theory and Application Elements In Decision Analysis
- Objectives and Values of Key Parties - Alternatives - Uncertainty - Consequences
Vulnerability Analysis
-Characterize forms of physical, social, political, economic, cultural, and psychological harms to which individuals and modern societies are susceptible -Millions of dollars have already been spent to reduce our vulnerability
Value-focused Thinking (Keeney)
-Deciding what you want based on your objectives/values -Determine what alternatives are available -Figuring out how to get what you want (Choosing best alternative) Values are Principles --> Used to evaluate consequences of action and inaction -Individual ( It is better to try and fail than not try at all) -Organization (Safety is our most important product) -Society (Make tradeoffs given scarce resources) Can articulate their meaning by translating them into objectives
Risk Assessment
-Encompasses estimates of both the chances of a specific set of events occurring and their potential consequences -Experts differ in their estimates of the risk -Find your favorite expert to support your position
standard view of decision making
-Specify set of alternatives from a narrow set -Focus on choices among given alternatives
Constructing Scenarios
-What are the probabilities of specific events? -What are the potential consequences?
problem types:
1 - cannot happen to me (flood insurance: extend time horizons, require for condition for mortgage) 2 - i am in control (provision of information, changing probability reference point, economic incentives) 3 - myopic behavior (economic incentives like low interest loans and premium reductions, well-enforced building codes) 4 - concern for my great grandchildren (siting perceived haz. facilities --> provision of info on risk, mitigation and control measures (local committee power to shut facilities down), compensation and benefit-sharing (direct payment to residents, grants to improve local service, local property value guarantees)
Steps in risk assessment process for carcinogens
1.Collection of toxicity information about the substance (Knowledge about properties of the substance and its effects) 2.Identifying whether substance represents a carcinogenic risk 3.Degree of risk substance might pose to humans 4.Extrapolation from animal risk estimates to potential human risk (How much of a dose will humans be exposed to)
Regulation Of Food Substances (Delaney Clause)
1958 Food, Drug And Cosmetics Act Banned All Carcinogens From Any Processed Food (I.E. Zero Risk) Experts Believed In 1958 Few Carcinogens Which Were Easily Identifiable Increasing Sophistication Of Measuring Techniques Identified Traces In Many Foods Congress Ignored New Findings Saccharin Was Found To Be Carcinogenic Exempt From Delaney Clause Due To Benefits Of Sweeteners Congress Replaced Delaney Clause In 1996 With More Realistic Standard Reason: Would Have Been Forced To Ban Many Pesticides And Hurt Farmers Crops And Food Prices New Standard: Reasonable Certainty Of No Harm Interpreted To Mean Lifetime Risk Of Cancer Of No Greater Than 1 In 1 Million
History of Fault Tree Analysis (FTA)
1962: Originally developed in 1962 at Bell Labs 1966: Boeing began using FTA for non-military aircraft design 1970: U.S Federal Aviation Administration (FAA) published a change in its regulations that led widespread use of FTA in non-military aviation 1975: U.S. Nuclear Regulatory Commission (NRC) began using probabilistic risk assessment (PRA) including FTA 1979: NRC expanded use of FTA following Three Mile Island accident and published a NRC Fault Tree Handbook in 1981. 1984: Bhopal disaster led chemical industry to use FTA widely 1992: OSHA published its Process Safety Management (PSM) standard that recognized FTA as an acceptable method for PRA Today: FTA is widely used in all major fields of engineering that deal with system safety
Now What Do People Know about Global Climate Change?Reynolds et al (2010)
2009 survey (248 respondents) replicates 1992 survey (177 respondents) on US public beliefs and attitudes toward climate change 1992---little official discussion of global warming 2008---both Obama and McCain proposed policies designed to reduce climate change Much uncertainty remains regarding climate change: Results from climate models are not understood by laypersons Confusion over weather and climate (e.g. does a blizzard mean global warming is a hoax) Dramatic weather events are highlighted by media (e.g. heat wave in France was used to exaggerate global warming) Most people felt human actions have changed global climatePeople exaggerated change in temperature in next 10 years Fewer respondents mentioned deforestation or other loss of biomass as a cause of global warming in 2009 (20%) compared to 1992 (57%) Greater recognition in 2009 that ozone depletion does not cause climate change. Only 3% mentioned this as a cause compared to 27% in 1992Greater appreciation in 2009 than 1992that excessive use of energy was a cause of global warming.
Non-experimental Studies:Case Control Design Example: Linking leukemia to exposure to benzene
400 person with leukemia vs. 400 matched persons without leukemia and look at benzene exposures Quicker and cheaper than cohort studies but subject to recall biases (e.g. persons with leukemia may be sensitized to their past benzene exposure and recall it more often than persons who do not have leukemia but were also exposed to benzene)
non market strategies
4Is -Issues? -Interests? -Institutions? -Information?
Findings from Climate Change Survey (June 2010)Ding et al Nature Climate Change (Nov 20 2011)
66% felt that where was no scientific agreement on global warming Many consumers find information to conform to their existing beliefs (Confirmation bias)---Intuitive thinking Need campaigns to indicate that it is a myth that climate scientists disagree that global warming is happening. •Provide correct information "Vast majority of climate scientists agree that human-caused global warming is happening"
Lessons from Nevada Initiative:
A Risk Communication Failure Role of Special Interest Groups (Anti-nuclear groups) Showed ANEC's purpose was not to educate but sway public opinion toward repository Nevadans were outraged (e.g. "Ron Ditto" radio show) ANEC campaign was discontinued in Spring of 1992
What is the precautionary principle and when was it invoked in the United States for addressing cancer risks?
Agencies and governments should minimize environmental risk by anticipating possible danger and where possible preventing it". The precautionary principle implies that one should set lowest possible standard when there is uncertainty on the risk. The Delaney clause is extreme version of the precautionary principle by indicating that any chemical should be banned if there was some chance of it causing cancer.
What type of sensitivity analyses would the Coast Guard want to undertake to determine whether or not to require the propeller guard?
Changes in the above mentioned factors .Changes in probability of injury or loss of life Changing value of life/injury (separate out these 2 factors) Effects on boat industry Moral Hazard - boat owners' riskier behavior given a guard is installed
Chemcare's Problem
Chemcare is utilizing a production process that exposes workers to a potentially toxic (carcinogenic) chemical. Currently those who are exposed to the chemical are at risk, although it is difficult to determine how many workers will contract cancer and how serious the disease will be. The company is responsible for covering all costs of hospitalization plus paying the worker's salary if one of its employees contracts cancer that can be shown with a high probability to have come from working with the toxic chemical.
Overstate risk posed by carcinogens for the following reasons:
Chemical which causes cancer in animals will do so in humans Assume greatest risk at lowest dose Use mathematical models that yield highest prediction of risk at low doses Do not assume threshold for any carcinogen
Gregory and Long "Using Structured Decision Making to Help Implement a Precautionary Approach to Endangered Species Management" Takeaways
Clarify the decision context Define objectives and evaluation criteria Develop alternatives Estimate consequences and identify uncertainties Evaluate tradeoffs Select preferred option, implement and monitor A SDM approach can avoid polarization between stakeholders by encouraging a focus on fundamental values and providing tools for facilitating informed and interactive deliberations rather than an adversarial process.
Exposure And Effects of Exposure Morgan Choosing & Managing Technology-Induced Ris
Concept 1: Exposure to the Risk Probabilistic - not clear person is increasing risk of cancer by being exposed to radon or working with chemical (May get small dose) Deterministic - certain that worker is being exposed to increased toxicity by being exposed to radon or working with a chemical
What two specific recommendations would you give VW for undertaking more deliberative thinking to avoid the problems they currently face?
Construct worst case scenarios if they would be caught by considering the impact that this would have on their future reputation and their future sales. Assign a likelihood to each of these scenarios. Stretch the time horizon so that the probability of being caught would be viewed as much higher than in just 1 year Examine the impact of installing the pollution devices on their market share and the potential negative consequences of this action
Three Supreme Court cases judging science
Daubert ---is Bendectin a carcinogen? Joiner ---do PCBs caused lung cancer? Kimho Tire----is automobile tire explosion due to manufacturing defect?
Assessing Risk: Role of Epidemiology
Definition: Study of the occurrence and causes of disease (and health) in human populations Today, use of epidemiology to determine causes of smaller, subtle effects of non-infectious agents: -Lifestyle-Nutrition-Chemicals Science is problematic: small effects background rates are high latency period often long
Pineda-Solana et al (2013) Lessons Learned from Fukushima Accident
Determine worst case scenarios as basis for design of plants Better preparation by industry to respond to natural disasters that trigger technological accidents (Natech disasters)ants
problems with precautionary principle
Doesn't consider tradeoffs between benefits and costs Regulation of arsenic in drinking water Cost $200 million each year E(Benefits): 6 lives saved per B/C ratio: $50 million per life Nuclear power banRelying on fossil fuels and coal fired power plants create other risks that contribute to global warming Global warming Mean temperature increase of 4.5 degrees C by 2100 $5 trillion in costs and many deaths from malaria
Gregory and Long "Using Structured Decision Making to Help Implement a Precautionary Approach to Endangered Species Management"
Endangered species management has had a mixed record of success in Canada for two principal reasons -Difficult to balance environmental (biological) goals against other societal objective such as economic benefits, recreation, health or safety -Scientific uncertainty regarding risks to endangered species Precautionary Principle (PP) has been used to justify actions to protect species at risk when scientific info is not available -(Better safe than sorry) -Cost of Type II error is much greater than Type I error) PP should be embedded in Structured Decision Making (SDM) framework that incorporates all the values of the key decision makers and how specific actions will change specific outcomes
Estimating Probabilities of Accidents and Their Consequences
Event Trees---Proceeds forward in time from a from a failure to their accident implications -Chance of 135,000 people killed from a liquefied natural gas explosion -Chance of $1 Billion Damage from an Earthquake in Oakland CA
What are two key differences between how experts and the public perceive and evaluate risk? Relate your answer to intuitive and deliberative thinking.
Experts focus on probability and actual losses while the public focuses on other dimensions such as fear, controllability, catastrophic potential Experts undertake deliberative thinking by taking into account probability and outcomes and computing expected costs and benefits (i.e. probability x consequences) in evaluating risks. The public exhibits specific biases such as availability and uses simple heuristics in evaluating risk such as it cannot happen to me
Lay and Expert Interpretations of Cancer Cluster Evidence by Levy et al Risk Analysis 2008 * Reasons for conflicts between laypersons (community members) and experts (public health officials)
Exposure: Laypersons believe some local agents was causing cancer even though experts indicated it was not Perception: Laypersons rate risks of cancer much higher than experts. Cancer is one of the most feared diseases Statistical Layperson tend to search for patterns when in fact they are random (cf. New Yorker article on Cancer Causing Myth)
Alternative Approaches For Regulating Food Substances
FDA - safe or not, worst case scenario risk classification approach -- Ban High Risks ( 10-2 Or Greater)Accept Low Risks (10-5 Or Less)Do Benefit Cost Analysis On Other Risks --> Challenges With This Approach: No Differences In Losses Benefits IgnoredNo Differentiation Between Individuals (E.G. Diabetics And Saccharin) Assumes Probabilities Are Known With Certainty Assess Both Risks And Benefits Of Banning Or Not Banning a Drug or Food Substance: costs/benefits, value of life?, aggregate individuals across population? decision process approach: how serious is hazard? subsidies? winners and losers? exceptions
fault trees
Fault Trees ---Always starts with the definition of undesired effect and reasons how it may have happened (Proceeds back in time to examine components of the system which may have caused the failure) -Probability of loss of electric power to safety systems -Probability car won't start
Technological Risk Assessment
Fault trees - how a negative event may have happened event tree - from failure to consequences probability car won't start (out of sight - out of mind) Chances of LNG accidents and resulting consequences - sitting an LNG terminal at Matagorda Bay
myopia
Focus on short-time horizons in comparing upfront costs of protection with expected benefits from loss reduction. remedy: Long-term mitigation loans coupled with insurance premium reduction
Risk Perception and Choice: Basic Concepts
Focuses on psychological and emotional factors that have been shown to have an enormous impact on behavior. -Hazards where individuals have little knowledge and experience are highly dreaded and perceived as being very risky -Disparity between experts and laypersons (e.g. nuclear power, storing radioactive waste) -Ignoring public's perception of risk by scientific community if it differs significantly from their own estimates
Amnesia
Forget the lessons of the past and decide not to undertake protective measures. remedy: Multi-year flood insurance contracts so property owners don't cancel their policy if they have no claims
Gregory and Long "Using Structured Decision Making to Help Implement a Precautionary Approach to Endangered Species Management" goals, objectives, alternatives
Goal: Develop management plan that would maximize conservation while enabling stakeholders to benefit from exploitation of Cultus Lake Specified four objectives: conservation, costs, catch and employment Developed 9 alternatives (columns) and evaluated them on the basis of different consequences (rows) Narrowed down alternatives to 3 based on alternative-consequence matrix by eliminating alternatives dominated by others Chose one alternative that had a precautionary alternative for conserving Cultus Lake sockeye and expanded it to 5 new variations of this alternative
Epidemiological Success Stories
Has established causal links between -Smoking and lung cancer -Radon gas and lung cancer (uranium miners) -Chimney soot and cancer in chimney sweeps (mid 1750's-first discovery of chemically induced cancer) -Benzene and leukemia* -20 chemicals and cancer
Features of Accidents
Hindsight---can blame operators after the fact but they were unaware beforehand Great events have small beginnings---coffee pot cracking started the process in "A Day in the Life" Hard to learn from accidents if one doesn't understand the cause (Importance of studying near misses) Tightly coupled systems make it hard for people to take independent action when something happens Organizations have their sins---warnings are ignored, deception and lying are practiced Tech fixes may reduce errors but are often an attempt to compensate for poor organizational design Complexity and coupling will produce catastrophes
Linking Multi-Year Home Improvement Loans with Multi-Year Flood Insurance
Homeowner: Lower total annual payments Insurer: Reduction in catastrophe losses and lower reinsurance costs Financial institution: More secure investment due to lower losses from disaster General taxpayer: less disaster assistance
Risk Management Strategiesfor Dealing with Extreme Events
Importance of decision process Information dissemination Economic incentives (insurance premium reductions; fines) Tradable permits to reduce emissions Regulations and standards (requirement for a mortgage) Third party inspections Insurance Liability
Gregory and Long "Using Structured Decision Making to Help Implement a Precautionary Approach to Endangered Species Management" considerations
Include all interested parties Consider a range of alternatives Include long-term effects (minimum of 2-3 decades) Consider precautionary actions to avoid undesirable outcomes Account for biological and outcome uncertainty tradeoffs between competing objectives identify social, economic, and conservation objectives key tradeoffs explicit highlight important factors in choosing between alternatives
risks for various groups
Individual Risk P = Probability Individual Is FatalityExample: All individuals exposed to risk 1.9 x 10-9 (1.9 in 1 billion) Group Risk Pjk = Probability Individual J In Group K Is Fatality Example: Transient daytime visitors 9.9 x 10-10 (Approx. 1 in 1 billion) Risk Of Multiple FatalitiesExample: Probability that at least 20 people are killed per year Societal Risk: Expected # Of Fatalities Per Year [ E(F) ]Example: 9000 people at riskRisk per person 1.9 x 10-9E(F) = 9000 x 1.9 x 10-9 =1.7 x10-5 (17 in 1 million)
system 1
Intuitive Thinking/ System 1: operates automatically and quickly with little or no effort Individuals use simple associations including emotional reactions Highlight importance of recent past experience Basis for systematic judgmental biases and simplified decision rules
non-market issue life cycle
Issue Identification----Specific crisis Interest group formation Legislation Administration Enforcement
Role of Affect & Availability Heuristics in Risk Communication: Key Findings
Keller Presentation of Information on Probabilities: - Frequency (Flood every 100 years) is more effective in emphasizing risk threat than probability (1 %) - Extending time period was more effective in emphasizing risk threat (Each year there is a 1% chance of a flood is less effective than I in 30 years there is a 33% chance of a flood) - Graphical information (pie charts) perceived lower risks than verbal information _____________________ Past Experience: - People who could remember images of floods assessed higher risk than those who did not - Presenting flood photographs increased perceived risk
Implications for Risk Communication
Know the issue (Nuclear waste facilities are viewed as unsafe so difficult to change people's mind) Create trust (Need to be honest; don't pretend everything will be OK) Provide unbiased reports (ANEC and DOE were viewed as "hired guns") Key Lesson: Risk Communication does not just mean presenting factsIt "must confront psychological, social, cultural and moral values that inform and shape public perceptions." (Flynn et al p. 502)
Nicholson-The REAL reason some people hate nuclear energy
Lack of trust Perceived risk exceeds perceived benefits Lack of control No ability to choose to have nuclear power plant (Yucca Mountain vs Finland) Radiation causes cancer Uncertainty as to likelihood and consequences of an accident It can happen to me Risk to my children
What is the Case For Banning Saccharin?
Legal Standards Past History---Banned In 1912 Protecting Public From Unsafe Products Extensive Testing
Indicate what factors the Coast Guard would take into account that the individual boat owner might not
Level of complianceGuard development costs and benefitsMedical costs cost to society of injuries may be higher than $50,000Value of life may be higher than $50,000 Perception of probability of accident by individuals may be different than what individuals perceivePolitical aspectsEffects on boat industryCosts to families and society from person dying or being injuredEthical and moral considerations----
Role of Quantitative Risk Assessments for Characterizing Risk and Uncertainty Aven and Renn Risk Analysis 2009 Characterization of Risk Problems
Linearity or Simplicity: Low complexity , uncertainties and ambiguities --> car accidents, life expectancy, smoking complexity: difficulty in identifying causal links ( LNG storage facilities, nuclear power plants, synergies re toxic substances (e.g. asbestos and smoking) uncertainty (large scale nat. disasters, terrorism)
Nature of Problem
Low probability event defined differently by individual and society - car accidents, leakage from radioactive sites preferences and values are vague, labile, and incoherent
Maintaining integrity of risk assessment process
Make explicit all assumptions and uncertainties Peer review of risk assessments Agencies separate risk assessment from risk management
market and non-market strategies
Market Strategies (Pricing and Production Decisions, marketing activities) Non-Market Strategies (Public-Private Partnerships) --> Voluntary: Firm Engages in Third-Party Inspections --> Non-Voluntary: Regulations; Well-enforced Standards, boycotts -interactions between firms and individuals, -cooperation between firms and interest groups -arrangements between firms and public sector
property values
McClelland Odors OII landfill accepted waste, closed as reached capacity people began to complain about odors, group formed to eliminate landfill problems then agreement to help clean up site from company experts say no negative health effects, people say yes
Long-Term Climate Change Objectives
Minimize adverse impacts of climate change Reduce net direct costs of climate change policies Address equity issues (distributional considerations) - countries, groups, generations, species, cultures
Actions to Reduce Risk of Cancer from RadonGinevan—Radon as an Indoor Air Pollutant
Modify the environment---Remove radon(e.g. Seal cracks in basement walls) Modify exposure processes---Spend less time in the basement Modify effects processes---Stop smoking: Smoker could have a risk of cancer as high as 15%A non-smoker could have a risk of cancer as low as 0.13%
Stigmatization and Social Amplification of Risk: The Alar Case
No scientific evidence that Alar was carcinogenic - Were based upon animal studies that were considered suspect because the doses used had been so large as to have been acutely toxic. - No evidence from epidemiological studies showing Alar to be a human carcinogen. The reaction by the public to Alar illustrates social amplification of risk. Media amplified the risk and effectively stigmatized the product (60 minutes)
Normal Accidents--Produced by
Normal Accidents--Produced by complexity and tight coupling Events are not independent ---interactive complexity Processes are tightly coupled---no organizational slack (time to spare to shut things off before they get worse)
Irrational Fears (of nuclear power) Myhrvold
Nuclear power is a source of carbon-emission-free-energy that is cheap, reliable and proven to work on a large scale. World Health Organization indicates that coal kills 4000 times as many people per unit of energy produced than nuclear power. Evidence from Fukishima - radiation killed no one, plant had 40 yr old design lacking in safety features, designed to withstand smaller tsunami lessons - build modern nuclear power plants, locate them in safe places reasons why gen. opposition - extensive media coverage, more than earth quake or tsunami, lack of trust due to organizations providing misleading information Policies based on fears rather than facts increase overall risks to the population - need reliable info and better risk communication Nature of Fukishima accident • No serious damage from earthquake • Tsunami left two reactor units (1 and 4) without power • No reports of fatalities from Fukishima accident due to radiation exposure
risk management strategies: mercury in fish
Pass regulations requiring restaurants serving fish and retail sellers of fish to provide warnings regarding consumption due to misperception of risk by public Testing of different species of commercial fish distributed by suppliers and ranking their quality based on standards set by the Federal Drug Administration and Environmental Protection Agency
global climate change values
Preserve eco-systems Preserve health Efficiency (Resource allocation) Equity (Don't harm certain countries, regions)
goals of epidemiology
Prevention of disease Reduction of adverse effects of disease: reduction of complications, prev. early death
cancer cluster myth reasons
Process by which cancer starts isn't straightforward Many causes of cancer---genetic defect, other environmental exposures, mutation Long delays between exposure and contraction Many people don't get cancer when exposed to it Would have to have a exposure to a very high dose We look for and remember clusters We look for causes when there are none
risk assessment vs. precautionary principle
RA---make tradeoffs between expected benefits and costs in setting standard (e.g. benzene) PP -agencies and governments should minimize environmental risk by anticipating possible danger and where possible preventing it (e.g. Delaney clause)
Decision Alaysis and Cost-Benefit: Theory and Application examples
Should Homeowners Inspect Their Homes for Radon? What is an Appropriate Standard for Benzene? What Are Appropriate Global Climate Change Policies?
What is meant by the social amplification of risk? In the context of the Alar case illustrate how the EPA might have been able to reduce it.
Social amplification of risk refers to the ripple effects associated with statement that a particular individual, place or product has a risk associated with it. In the case of Alar, there was social amplification due to Meryl Streep's comments and the 60 Minute program that convinced parents that they should not give apple juice to their children. As a result there was a substantial drop in demand for apples that had a very negative impact on apple growers in Washington. EPA could have reduced this social amplification by providing much more specific data on what the experts knew about Alar; limited evidence that it was a carcinogen; educate the media and public on the difficulties of extrapolating risks to children from animal studies; prepare Dr. Moore more for his interview; not focus on institutional failures, which creates perception that EPA is looking for excuses; issue temporary product withdrawal not outright ban.
Cost-Benefit Analysis
Societal Viewpoint Tensions Between Efficiency (Resource Allocation) and Equity (Distribution) _____________________________________ Typical problems: Regulating Benzene (OSHA) Specifications on Gas Tanks (NHTSA)
Matagorda Bay, Texas
Sparsely Populated Area 120 Mi. SW Of Houston Receives And Distributes LNG From Algeria Potential Risks: Spill From Ship Due To Collision LNG Spill and Ignition of Vapor Cloud P(Collision Releasing One Tank Of LNG) P(No Ignition In This Collision) P(Wind Is From East) P(Wind Is 10 Mph) P(8th Ignition Source Ignites Vapor Cloud) Probability for This Scenario is 2.71x 10-12 Worst Case Scenario Suppose this Event Occurred In Tourist Season Total E(Fatalities) = 366.46 Risk From Fire To Average Individual is 16,000 Greater Than Risk To Individual Exposed To Proposed Terminal 65 Meteorites Weighing More then 1 Pound Hit the US Each YearProbability That 1 of 65 Meteorites Hitting Your House Each Year (1.9) X (10-9).Identical To Individual Risk From LNG Terminal At Matagorda B
decision analysis
Structuring the Problem (Alternative Strategies) Assessing the Risk (Probabilities and Consequences) Evaluating Alternatives _____________________________________ Typical Problems: Checking house for radon (Green's) investing in new production process (Chemcare) redesigning gas tank (Ford Excel)
Risk Management Strategies Economic Incentives
Subsidies: Vouchers and low interest loans to those requiring special treatment (e.g. low income residents in hazard-prone areas) Fines: Raising fines to $300 million on carmakers that botch or slow-walk recalls manufacturers Role of Insurance: Premium reductions on insurance policies to encourage property owners to invest in adaptation measures to reduce future flood-related losses due to climate change and sea level rise
OSHA'S Benzene Standard Problem
The Occupational Safety and Health Administration (OSHA) finalized a standard for benzene which requires a permissible exposure limit of 1 parts per million because of the possibility that a person in the work place may contract leukemia. This standard has been challenged by the American Petroleum Institute because it claimed that OSHA had failed to demonstrate a relationship between the costs of the new standards and the expected health benefits. The total costs for companies to meet this standard is in the millions relative to the previous OSHA standard of 10 ppm. The relationship between exposure to small amounts of benzene and contraction of leukemia is not well-specified. Should OSHA relax its standard, and if so, to what level?
What is the availability bias and how does it affect people's perception of risk? Provide a simple illustrative example.
The availability bias indicates that a person assesses the probability or frequency of an event by how easily the event is recalled. If one has personally experienced a disaster or knows of someone who has suffered losses there will be a tendency to focus on this event and estimate the probability of its occurrence to be greater than statistical data would suggest. Examples: Shark kills, car accidents, Bhopal Chemical accident
Suppose that the federal government was considering requiring air bags in all cars. Using the concepts of benefit-cost analysis, what rationale would the federal government use for requiring air bags rather than leaving this up to the automobile manufacturers?
The federal government is concerned with the impact of safety on all the relevant interested parties. If those who purchase cars misperceive the probabilities of an accident and/or are myopic so they are not willing to spend the addition money on a car with an air bag then it may be appropriate for the government to require these measures for the following reasons: • Reduction in loss of lives and injuries if one requires air bags in all cars • There will be a lower manufacturing costs of air bags if all cars have to install them. • Negative externalities---the general taxpayer may cover some of the hospital expenses of victims.
Indicate two examples of intuitive thinking by VW that may have lead them to cheat on their emissions test.
The likelihood of being caught is below my threshold level of concern The benefits of selling more cars and capturing market share is our dominant challenge so we won't think about the negative consequences of being caught.
Suppose that Chemcare is considering using the production process for more than one year. How will this affect their decision on whether to invest in a new process if they were indifferent between investing and not investing over a one-year time horizon?
This decision involves the tradeoff between discounted costs of future cancers and the one-time undiscounted cost of investing in the new production process now. This trade-off depends on probabilities (p, q's), the number of workers and the discount rate. However, if Chemcare is concerned that workers exposed to toxic chemical for a longer period of time are more likely to contract cancer this will sway them to invest in a newer production process. If Chemcare expects the production process to go for more than 1 year then it will be more likely to invest in it for any given values of p(+) and q's since it incurs the fixed cost of the process once and will save cancer-related costs over a longer period of time.
Epidemiological MethodsExperimental Designs
Treatment group vs. control group Used to study new medicines (clinical trials), Can't use to study effects of pesticides on humans Problem:You need tens of thousands of patients (cases) to detect rare side effects of medicines
Role of Affect and Availability Heuristics in Risk Communication - Keller et al
Two modes of thinking Analytic System: Relies on probabilities, logical reasoning and evidence Experiential System: Relies on images, metaphors and evidence ___________ Factors use by Experiential System to Assess Risks Affect related to a hazard in estimating probability (availability heuristic) Past experience as a way of assessing risk
optimism
Underestimate the likelihood of extreme events; they are below one's threshold level of concern treat low probabilities as zero probabilities remedy: Stretch time horizon so that homeowners pay attention: probability of 1-in-100 annually is 1-in-4 chance of at least one flood in 25 years
Viscusi and Zeckhauser "The Perception and Valuation of the Risks of Climate Change: A Rational and Behavioral Blend" Climate Change (2006)
Undertook a survey of 257 students in 2004 (133 from Harvard Law and 124 from Kennedy School)(70% response rate) Goals of study •How individuals estimate risks of climate change •WTP to avoid climate change risks•Identify biases in risk assessment and WTP •Role of uncertainty in affecting policy choices
VW case
Volkswagen installed software in 500,000 diesel cars sold in the U.S. that cheated on emissions tests, allowing the vehicles to get higher miles per gallon of gas by spewing far more deadly pollutants than EPA U.S. regulations allowed .
Strong Version of Precautionary Principle
When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not established scientifically. In this context the proponent of the activity, rather than the public, should bear the burden of proof Wingspread Declaration (1998) Burden of proof is on scientists to show that product is harmless before it can be used
new mammogram age
Women with an average risk of breast cancer have mammography starting at age 45 and continuing once a year until 54, and then every other year for as long as they are healthy and likely to live another 10 years.
simplification
attending to only a few of the relevant factors remedy: focus on the potential consequences of a flood rather than on its probability
herding
basing one's choices on the actions of others remedy: Seals of approval with certified inspections on well-designed property to create a social norm for protection in hazard-prone areas
dealing with stigma
better design of products and facilities increase trust public participation in decision making
process models
continent weighting model (pre and post accident behavior) threshold models
system 2
deliberative / System 2 allocates attention to effortful and intentional mental activities •Individuals undertake trade-offs implicit in benefit-cost analysis •Recognizes relevant interconnectedness and need for coordination •Focuses on long-term strategies for coping with extreme events
dose-response curve
dose-response relationship, or exposure-response relationship, describes the change in effect on an organism caused by differing levels of exposure (or doses) to a stressor (usually a chemical) after a certain exposure time, or to a food.[1] This may apply to individuals (e.g., the dose makes the poison: a small amount has no significant effect, a large amount is fatal), or to populations (e.g.: how many people or organisms are affected at different levels of exposure).
reducing social amplification
educate media media thinks performing service (first amendment, oprah and british beef) educate government
Consider determining whether a technological process is risky. What specific approaches would you utilize to determine this?
fault trees event trees
technological risk assessment
fault trees event trees applications: risks from LNG terminal, estimating danger from natural diasaster
risk perception
how people view risk - multi-dimensional aspect of risk - differences between laypersons and experts - hurricane florence role playing risk perception and stigma: - social amplification of risk - siting landfills and perceived hazardous facilities - impact on property values (odors and housing prices) - impact on price of apples with Alar
cancer cluster myth idea
if true neighborhood clusters are so rare, why do we see so many? —> programmed to ... nearly all of them result of almost irresistible errors in perception Belief in the Law of Small Numbers — assume that pattern of large population will be replicated in all its subsets but clusters will occur simply through chance McFarland, CA — childhood cancer rate four times as high as expected
risk perception: Individuals exhibit ____________ in processing information and making choices Individuals have difficulties learning due to biases and information processing limitations individuals have difficulties
individuals exhibit systematic biases in processing information and making choices •Estimating likelihood of event is influenced by salience (availability bias) •"It cannot happen to me" bias before a disaster •"It will happen to me" bias after a disaster •Framing of information may influence choice ____________ Individuals have difficulties learning due to biases and information processing limitations These are examples of intuitive thinking (System 1)
social amplification of risk and stages
initiating event - accident, chemical release, government report sources of info - communication of risk through mass media, friends and neighbors, personal experience ripple effects - radiate from affected people to local group and society impacts - econ losses, mitigation, reg. actions, community concerns, loss of trust
GM case: 4Is
issues - Safety of GM Chevy and GMC full-size pickup truck due to fuel-tank related deaths and side-impact crashes interests/institutions - Center for Auto Safety, Popular Hot Rodding, Hughes Aircraft, Media—NBC (Dateline) information: 1992 Center for Auto Safety recalled 5 million Chevy and GMC trucks claiming 300 people died in side impact accidents GM has moved gas tank from outside main frame to inside frame in 1987 GM Settled 140 fuel tank-related lawsuits without media publicity (Mostly out of court) Tested trucks with side-impact crashes at 30 mph and 50 mph Institute for Highway Safety claimed GM trucks were 2.4 more likely than Ford's to be involved in side-impact crashes Nov. 1992 Dateline NBC aired show "Waiting to Explode?" to 11 million viewers claiming it had conducted tests saying fire occurred at 30 mph GM requested test data but NBC refused saying vehicles had been junked Pete Pesterre (Editor of Popular Hot Rodding) wrote editorial criticizing Dateline GM acquired tapes from off-duty sheriff and showed speed was 47 mph GM inspected wrecked vehicles and concluded starter device had been wired to rocket engine, gas cap was non-standard and fuel tanks had not been punctured
principles of risk com.
know audience get attention translate scientific data to concrete data
Weak Version of Precautionary Principle
lack of decisive evidence of harm should not be a ground for refusing to regulate (Risk-based approach) Requiring individuals to wear seat belts Drug regulation Clean Air Act Amendments require firms to develop risk management plans for reducing likelihood of accidents
Why Precautionary Principle is Advocated
loss aversion myth of benevolent nature availability heuristic - focus on salient risks probability neglect - focus on consequences not probability system neglect - nuclear power ban and global warming
Inertia
maintaining the status quo because of the time and effort to change and the uncertainty of the outcome remedy: Add flood coverage to homeowners policy as the default option with an option to cancel it
stigma
mark placed to signify disgrace causes - widespread fears and perception of risk (Alar), lack of trust (TMI accident), concerns about equitable distribution of benefits and costs (Yucca)
Health Risk Assessment
measuring risk: - many different measures - toxicology and its role - epidemiology and its role techniques and applications: - dose-response curves - regulating food substances - Delaney clause and saccharin - mammogram role playing
uses of fault trees
nuclear power plants - chance of an accident Boeing - design of large aircraft Alcoa - safety of large furnaces (shut-off valves reduced likelihood of explosion by factor of 20) chemical companies - where to build plants and design transport routes
reduce stigma impacts
provide insurance on brownfield insure new facilities price anderson act - low limit on liability, signal that nuclear power safe or insurance industry so worried didn't want higher value guarantee prop values provide compensation
Goiana, Brazil
radioactive material from junk yard 100,000 people standing on line for radiation monitoring 50% drop in v of ag production number of homes and prices plummeted tourism fell accident used to mobilize against nuclear power
Risk Assessment & Vulnerability Analysis includes
risk assessment vulnerability analysis constructing scenarios
Type I error
saying that a substance is harmful when it is not
Type II error
saying that a substance is not harmful when it is
Why Experts May Disagree
scientific uncertainty uncertainty about models dispersion of vapor clouds different sources of data imagination (E.G. Earthquake Causing Tank Rupture; Sabotage) uncertainty about consequences training and background assumption background assumptions -- no. of people at risk
Attributes for determining whether association means causality
strength of association (chimney sweeps dying of scrotum cancer) consistency across studies specificity to a particular organ or group of people (e.g. scrotum cancer and chimney sweeps) temporality -- does observed effect follow the cause? biological gradient -- effect increase with dose plausibility -- is claimed casual relationship plausible? (storks/babies) coherence -- is relationship coherent with other data? experiment -- did effect vanish when cause was removed?
arguments against precautionary principle
• Does not take into account risk tradeoffs with benefits • By prohibiting certain activities (e.g. construction of nuclear power plants) you may increase risk facing society (e.g. increased air pollution and CO2 thru coal-fired plants) • Threshold value of safety may be inappropriate • Different people face different risks • Maybe an unfair shift in the burden of proof • Experts opinions invariably differ • There is a myth of a benevolent nature • Risk assessment is a starting point for reaching conclusions as to what risks to regulate • Degree of uncertainty associated with any risk assessment should be considered • Need deliberative democracy by hearing views of different interest groups • Inhibits innovation
Consider testing a chemical to see whether it is carcinogenic. Indicate what specific approaches you would utilize to determine this.
• Dose-response curves • Epidemiological studies
What are the challenges in assessing whether or not the process is dangerous?
• Fault trees determine the factors that may cause an accident while event trees depict a sequence of possible scenarios that can lead to specific outcomes. • Both these methodologies require a careful specification of the likelihood of certain events occurring and their respective consequences. • There may be great uncertainty on both these dimensions. One needs to consider interdependencies with respect to the likelihood of accidents occurring and their consequences.
Based on the risk perception literature specify 4 reasons why the U.S. public has been concerned with nuclear power as a source of energy since the Japan accident?
• Fear and dread associated with nuclear power and image of a catastrophic accident. • Accident may have been a signal for something worse to common. The Japan accident has reinforced this image • Experts disagreeing on the causes of the accident and period of time right afterwards when none knew what had happened • Concern for future generations and what would happen to them • Stigma regarding "nuclear power plants" created by the accident—social amplification of risk in the sense that a possible source of energy has been stigmatized. • Media made the public more concerned of the potential danger of nuclear power. • Availability Bias • Lack of control. • Lack of trust in government was discussed by some people- • Other answers were judged on a case by case basis (depending on argument and validity)
What are the challenges in assessing whether or not the chemical is dangerous to one's health?
• Often animals (e.g. rats) are exposed to high doses of the chemical which are then extrapolated down to the dose likely to be experienced by humans to indicate what the individual likelihood is of getting cancer. • There are problems because it is not clear how to extrapolate from high to low doses and whether animals have the same sensitivity to the chemical as humans. • Different populations may be more/less sensitive to exposure to this chemical and there may be a latency period between exposure and effect. • Epidemiological studies are costly and setting the appropriate controls is difficult and causality is difficult to determine
Outline four elements of a risk management strategy that utilizes risk assessment concepts while recognizing the risk perception issues you noted above to convince the government and the public that it might be would be advisable to construct more nuclear power plants in the near future.
• Specify probabilities and consequences associated with future accidents from a well-designed nuclear power plant • Arrange for regular inspections that those residing in the region feel safe • Communicate information on the likelihood of an accident and its consequences relative to other sources of energy similar to what was done for the LNG facility proposed for Matagorda Bay. • Provide non-monetary compensation to the residents of the community (e.g. better health facilities) • Show the general public that nuclear power reduces likelihood of severe climate change that would occur if we continue to use coal as a major source of energy
Green's radon values/objectives
•Health/maintain children's health •Costs/minimize costs •House/maintain value •Peace of mind/act, don't act (ignorance is bliss) •Stability/stay put
Three Mile Island
•Moisture in instrument air line sends false signal to turbine (Failure 1) •Turbine stops •Emergency feedwater pumps start •Flow blocked because valve is closed instead of open (Failure 2) •Rise in core temperature and pressure •Pilot Operated Relief Valve (PORV) opens •PORV told to close but sticks open (Failure 3) •PORV position indicator signifies it has shut (Failure 4) Probability of nuclear plant meltdown is "not one chance in a million a year but one chance in the next decade" President's Commission----human error Metropolitan Edison---mechanical failure (faulty valve) Nuclear Regulatory Commission—design of system (poor control room)
Risks Associated with Mercury in Fish
•The age of the person exposed (the fetus is the most susceptible); •The route of exposure -- inhalation, ingestion, etc.; •The duration of mercury exposure;•The dose amount; •The chemical form of mercury (methylmercury is more toxic than elemental mercury); •The health of the person exposed
Exposure And Effects of Exposure
•Uncertain effect - no cancer / cancer r•Deterministic effect - cancer