Addressing the topic of risk in the modern world may be the greatest challenge facing industrial hygiene. “Protecting Worker Health,” the tagline of AIHA and guiding light of our profession, fundamentally focuses on managing hazards and reducing risks through application of the scientific and technological regime known as awareness, anticipation, recognition, evaluation, control, and confirmation (AARECC). But there comes a point in every risk analysis when the question arises, “what else can reasonably be done?”

This article explores the challenge of risk, explains how to get started in mastering the art and science of risk decision making, and suggests a better way for our profession to take on the risk challenge in the modern world. THE CHALLENGE: HAZARDS, RISKS, AND “SAFE” Let’s be honest: it is not possible to eliminate all hazards and risks, and solutions to risk-related problems always introduce new and different risks. Every risk has benefits, costs, upsides, and downsides. One person may see the outcomes of a risk analysis as stimulating and worth taking while another may see the same outcomes as terrifying and not worth chancing. Judging the value of the risks and their respective benefits, costs, and rewards is where decision making can become prickly. It seems obvious that everyone wants to participate in the upside of risk and nobody wants to participate in the downside. Nobel Laureate Daniel Kahneman and Amos Tversky observed this fundamental human behavior in their 1979 paper “Prospect Theory: An Analysis of Decision under Risk.” Direct applications of their pioneering work to our profession include Kahneman’s 2011 book, Thinking, Fast and Slow, which contrasts automatic, subconscious decision making with conscious decision making. Risk and consequence are relevant to more than just a job analysis. We seek a balance between risk and consequence in every aspect of decision making throughout our lives. Every day, each of us makes hundreds of conscious as well as unconscious risk/reward decisions. Sometimes the consequence of an event is “simply” a bruised ego, a missed appointment, or a Band-Aid; other times the same event could send someone to the hospital or worse. A minor cut has different consequences for a hemophiliac than for a person whose blood clots normally. The AIHA Risk Committee has been advancing the science of risk decision making through a five-step process: assessment, characterization, communication, analysis of benefits and costs, and management. Systematically considering each of these five steps through a process called structured decision making can help the industrial hygiene profession find safe ways for people to work with hazards and risks.  TENSION AND PARADOX Risk management and decision making are full of tension and paradox. After all, while assessing risk is cognitive, interpreting the assessment involves human judgment rooted in emotions. Tension is present when numerous values are in play—for example, consider the often-competing interests of labor and management. Paradox is present when something appears to be other than what it is; compliance with regulations and consensus standards can introduce paradox because compliance doesn’t necessarily mean risks have been eliminated. Some aspects of risk management and decision making likely to involve tension and paradox are discussed below. Uncertainty and complexity. Uncertainty is at the core of risk science. Most if not all risk-related activities are attempts to increase certainty or to control for uncertainty. OHS risk-related decision making has become more challenging as risk profiles—the number, types, and potential effects of risks—have become more complex and the expectations of workers and the public have evolved. Today’s complexities stem both from a “modern” perspective on traditional workplace exposures related to materials, chemicals, and processes as well as the public’s understanding of terms such as “Legionella-free,” “gluten-free,” sodium-free,” and “lead-free.” In none of these examples  does “free” mean “zero”; rather, these terms indicate the acceptability of some residual amount that does not meaningfully increase risk. Complexities stem also from new considerations such as supply chains and changing definitions of who is a “worker” and who is an “employee.” 
Context. Individuals make decisions every day that reflect how they value health and mortality risks, such as driving an automobile, smoking a cigarette, and eating a medium-rare hamburger. There are no cost-free or risk-free decisions; each choice involves trade-offs and judgment of the risk-reward balance. Many choices involve market-based economics, such as using a hazardous product or working on a risky job. Because increases in health risks are undesirable, there must be some other aspect of the activity that makes it attractive. Context becomes more complex as risk management raises issues about “whose risk” and risk appetite as well as the insurability of transferred risk. Residual risk. Residual risk gets at the core of risk decision making and management. The conundrum in risk decision making reveals itself when we recognize that zero risk is impossible to achieve. At best, we manage to achieve a residual risk that is not unacceptable and thus defined as safe. Even when residual risk is low (for example, 1 in 10-3) or extremely low (1 in 10-53), risk for the population cannot be zero, and humans will judge a risk according to its consequence, not its probability. If an undesirable consequence occurs—and there are undesirable consequences associated with every hazard and risk—then surely someone must be to blame for “allowing” it to happen. From a government perspective, all policy choices ultimately involve balancing additional risk reduction and incremental costs as well as society’s willingness to pay for the benefits. Based on implicit tradeoffs between risk and money, economists have developed estimates of the “value of statistical life” (VSL), which provide a reference point for assessing the costs and benefits of risk reduction efforts and government risk policies ranging from the draining of swamps near ancient Rome to suppress malaria to the limits on air pollution in developed countries over the past 30 years.  Perception vs. science. Perhaps the most vexing aspect of risk is the tension between risk perception and science. People judge the consequences and outcomes of risk according to their emotions and perceptions, yet the calculation of risk is cognitive and scientific. Emotions are essential to decision making because positive emotions are often the desired ends of our decisions, but we can only choose what course to take if we know what will make us happy. Industrial hygienists who recognize this paradox can communicate more effectively while engaging workers, management, and the public, being leaders in innovative thinking, and exploring the soundness of risk management considerations. Emotional response. As much as we might like to think humans are rational creatures, we are driven by beliefs and emotions. Kahneman and Tversky showed that humans systematically make choices that defy clear logic. We simply don’t have the time or capacity to calculate the statistical probabilities and potential risks that come with every choice. Most truly important decisions rely at least in part on subjective preferences. Some may call these preferences “instincts”; in fact, they are not instincts but heuristics—learned mental shortcuts that allow our subconscious to focus on one key factor to make a decision, rather than taking into account every tiny detail. RISK MANAGEMENT SYSTEMS AND WORKER HEALTH  The International Organization for Standardization recently published ISO 45001, the first global standard for occupational health and safety management systems. According to ISO, the standard

provides a framework to improve employee safety, reduce workplace risks and create better, safer working conditions, all over the world.… [ISO 45001 was] developed by a committee of occupational health and safety experts, and follows other generic management system approaches such as ISO 14001 and ISO 9001. It will take into account other International Standards in this area such as OHSAS 18001, the International Labour Organization’s ILO-OSH Guidelines, various national standards and the ILO’s international labour standards and conventions.
ISO 45001, like all other regulations, consensus standards, and policies, does not purport to eliminate risks or ensure no worker will ever be injured or develop an occupational disease. We return to the reality that zero risk, if that is the objective, is not attainable.  Risk is context-dependent, and judging risk demands upfront agreement on terms, units of measure, and metrics. To what or whom is something a risk—the organization, the worker, the community, the environment, or the biota? Depending upon the context, a risk may be acceptable (or not unacceptable), which we define as “safe.” As risk management concepts have evolved, more attention has been placed on notions such as “responsible party,” “risk owner,” “risk transfer,” and “sustainability.” But the Occupational Safety and Health Act places the responsibility upon the employer to provide a work environment “free from recognized hazards that are causing or are likely to cause death or serious physical harm.” Today, when it can be difficult to identify both the workplace and the employer, the question arises, “who controls the place of work, and thus, who is responsible for health and safety?” STRUCTURED DECISION MAKING Risk analysis and risk management decision making need to be systematic and structured. Structured decision making is a term for organized analysis of problems to reach decisions that are focused on achieving defined objectives. In structured decision making, every decision comprises several primary elements—management objectives, decision options, and predictions of outcomes. Analyzing each of these elements separately and thoughtfully leads to improved decision making. Structured decision making is as useful for minor, personal decisions as it is for complex public-sector issues involving multiple decision makers, scientists, and stakeholders. The steps of structured decision making are: 1. Define the problem. What decision has to be made? What is the spatial and temporal scope of the decision? Will the decision be iterated over time? 2. Define objectives. Management objectives should be measurable. Setting objectives falls in the realm of policy, and should be informed by legal and regulatory mandates, as well as stakeholder viewpoints. 3. Define alternatives. What are the different management actions to choose from? The range of permissible options is often constrained by legal or political considerations, but creative new alternatives may be found. 4. Analyze consequences. What are the consequences of different management actions? How many of the objectives would each alternative achieve? This step may use a model to predict the consequences of the alternative actions. Depending on the information available or the quantification desired, consequences may be modeled, ideally, with computer applications or with careful and transparent personal judgment. 5. Analyze tradeoffs. If there are multiple objectives, how do they trade off with each other? In most complex decisions, the best we can do is choose intelligently between less-than-perfect alternatives. Numerous tools are available to help determine the relative importance of conflicting objectives and to compare alternatives to find the “best” compromise solutions. Clearly, the analysis of consequences and tradeoffs involves judgments of values, preferences, and risk attitudes. 6. Acknowledge uncertainty. Decisions are frequently made in the face of uncertainty, which makes choosing among alternatives more difficult. Confront uncertainty and evaluate the likelihood of different outcomes and their possible consequences. 7. Understand risk tolerance. Identify the greatest uncertainty that clouds decision making and analyze the risk related to that uncertainty. The decision- making process will be more objectives driven, transparent, and defensible if informed by an understanding of the level of risk a decision maker is willing to accept. 8. Sequence linked decisions. Many important decisions are linked over time. The key to dealing effectively with linked decisions is to isolate and resolve the near-term issues while sequencing the collection of information needed for future decisions. For example, when addressing supply-chain questions, initially focus on issues that are causing adverse effects right now before investigating more insidious issues. THE SCIENCE OF CHOICE NIOSH’s Total Worker Health initiative has expanded the domain of the industrial hygienist beyond our traditional focus on exposure and on ensuring that work is safe and that workers are protected from the harms that arise from work itself. According to NIOSH, Total Worker Health “builds on this approach through the recognition that work is a social determinant of health; job-related factors such as wages, hours of work, workload and stress levels, interactions with coworkers and supervisors, access to paid leave, and health-promoting workplaces all can have an important impact on the well-being of workers, their families, and their communities.” Total Worker Health clearly goes beyond any regulation, consensus standard, and policy. Perhaps Total Worker Health is clear demonstration of AIHA’s tagline, “Protecting Worker Health.” If Total Worker Health fulfills our mission to protect worker health in today’s globalized and nebulous place of work, how does our profession meet the challenge? What additional skills do we need to learn? Historically, we’ve focused on workplaces (factories, offices), but today more than 30 percent of the U.S. labor force comprises contingent workers whose places of work may not meet the definition a “workplace” in OHS laws and regulations. How can the science of choice help forward-looking industrial hygienists build healthy places of work? Are the topics of “residual risk” and “safe” the best lens through which we can provide the greatest value to employers, workers, the public, and the environment? These challenges, as well as inherent tensions and paradoxes, can be addressed by mastering structured decision making across the five dimensions of risk science: assessment, characterization, communication, analysis of benefits and costs, and management.    FRED W. BOELTER, CIH, PE, BCEE, FAIHA, is principal at RHP Risk Management Inc. He can be reached via email. CHARLES F. REDINGER, PhD, MPA, CIH, FAIHA, is president of Redinger 360, Inc. in Harvard, Mass. He can be reached via email. Send feedback to The Synergist.

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Structured decision making is as useful for minor, personal decisions as it is for complex public-sector issues involving multiple decision makers, scientists, and stakeholders.
Improve Risk Analysis through Structured Decision Making
Risk in the Healthy Place of Work
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Disadvantages of being unacclimatized:
  • Readily show signs of heat stress when exposed to hot environments.
  • Difficulty replacing all of the water lost in sweat.
  • Failure to replace the water lost will slow or prevent acclimatization.
Benefits of acclimatization:
  • Increased sweating efficiency (earlier onset of sweating, greater sweat production, and reduced electrolyte loss in sweat).
  • Stabilization of the circulation.
  • Work is performed with lower core temperature and heart rate.
  • Increased skin blood flow at a given core temperature.
Acclimatization plan:
  • Gradually increase exposure time in hot environmental conditions over a period of 7 to 14 days.
  • For new workers, the schedule should be no more than 20% of the usual duration of work in the hot environment on day 1 and a no more than 20% increase on each additional day.
  • For workers who have had previous experience with the job, the acclimatization regimen should be no more than 50% of the usual duration of work in the hot environment on day 1, 60% on day 2, 80% on day 3, and 100% on day 4.
  • The time required for non–physically fit individuals to develop acclimatization is about 50% greater than for the physically fit.
Level of acclimatization:
  • Relative to the initial level of physical fitness and the total heat stress experienced by the individual.
Maintaining acclimatization:
  • Can be maintained for a few days of non-heat exposure.
  • Absence from work in the heat for a week or more results in a significant loss in the beneficial adaptations leading to an increase likelihood of acute dehydration, illness, or fatigue.
  • Can be regained in 2 to 3 days upon return to a hot job.
  • Appears to be better maintained by those who are physically fit.
  • Seasonal shifts in temperatures may result in difficulties.
  • Working in hot, humid environments provides adaptive benefits that also apply in hot, desert environments, and vice versa.
  • Air conditioning will not affect acclimatization.
Acclimatization in Workers