Society demonstrates a willingness to tolerate high levels of risk to individuals who participate in certain types of activities. Every day, firefighters, law enforcement officers, other first responders, and military service members put their lives and health at risk in defense of persons, property, national security, or other compelling public interests. Other individuals volunteer to participate in biomedical research, which can pose significant health and safety risks. Additionally, many individuals engage in other high-risk occupational and recreational activities with limited external oversight.
As described in Chapter 1, the National Aeronautics and Space Administration (NASA) asked the Institute of Medicine (IOM) to convene the Committee on Ethics Principles and Guidelines for Health Standards for Long Duration and Exploration Spaceflights to identify ethics principles and develop an ethics and policy framework to guide decisions about long duration and exploration space missions, when risks associated with working conditions fail to meet current health standards or when uncertainty prevents development of adequate health standards. As part of its charge, the committee was asked to identify “models or examples of other situations with unknown health risks (or risks that could exceed current standards) that could inform NASA policy and, if so, how?”
In identifying other occupations and situations from which to draw, the committee considered the multiple roles of astronauts and NASA. As key figures in high-risk missions, astronauts concurrently serve a multitude of roles and responsibilities. Astronauts are employed as part of a mission crew, operating as a team to minimize risks to individuals and improve the likelihood of mission success. Each NASA crew performs a variety of mission functions, which may include flight management,
operations, repairs, retrievals, and research (such as medical experiments). Beyond mission-related responsibilities, astronauts serve in a number of public roles, including federally sponsored explorers. Given that space missions are pursued for public good by a federal agency, astronauts are also public servants. Astronauts often participate in research as investigators and also as research volunteers. Similarly, NASA, as a federal agency, plays numerous roles (e.g., employer, research sponsor, international partner, and science educator) and bears responsibilities to various stakeholders with interests in space exploration.
The presence of highly uncertain and unquantifiable health and safety risks is not unique to human spaceflight. Many domains have negotiated similar challenges in decision making about risk acceptability. However, the degree to which ethics principles are incorporated into a formal decision record varies greatly by occupational domain and profession within a domain. The committee consulted the scientific literature about existing frameworks and spoke with many experts in other high-risk occupations, but was not able to identify existing ethics frameworks or decision-making models for specific occupations that were directly and wholly applicable to decisions about health standards for long duration and exploration spaceflight.
From existing ethics frameworks and available occupational health standards, the committee sought to identify common factors that could be used to inform committee deliberations about ethics principles and frameworks. The committee found examples in occupational health, research, and exploration that provided useful points for comparison. The first three sections of this chapter examine these domains for useful examples of risk management strategies and duties and, to some extent, identify relevant societal interests. The last section draws from these examples to categorize and synthesize examples of common factors that appear to influence decisions about risk management in terrestrial settings.
This chapter does not provide an exhaustive list of occupations and activities that involve high risk to participating individuals. Rather, it provides a few key examples that were selected based on characteristics that are applicable to human spaceflight and because they provide useful insights about the types of factors that may affect decisions related to risk management. Additionally, the factors identified are meant to be illustrative and not an exhaustive list of all factors that could be relevant to discussions about the risks of human spaceflight.
RISK MANAGEMENT IN THE WORKPLACE
Efforts to protect the welfare of workers in the United States have been documented since the late 19th century and have led to significant improvements in worker health protections. As described by some in the literature, occupational health regulations and standards “aim to promote and maintain the highest degree of physical[,] mental and social well-being of workers in all occupations; to prevent decline in health caused by their working conditions; to protect workers in their employment from risks resulting from factors adverse to health; and to place and maintain workers in an occupational environmental adapted to their physiological and psychological capabilities” (Serra et al., 2007, p. 304). In many high-risk occupations, health regulations and standards, in addition to serving the interests of individual workers, may also protect the health and safety of others (including bystanders and co-workers), equipment and property, and the integrity of the work enterprise.
Depending on the specific job hazards, employers (including NASA) use a multi-tiered approach to comply with established exposure limits and health and safety regulations. Employees also may be obligated to comply with these regulations and limits, without an option to waive mandatory employee protections, using a variety of techniques and controls, such as:
- Elimination of the hazard or substitution of less hazardous materials in the work process;
- Engineering controls and redesign of the work environment to limit exposure (e.g., ventilation, enclosure and/or isolation of emission source, process control);
- Administrative controls (e.g., length of work in a particular area, decision protocols); and
- Personal protective equipment and adequate training on correct use (e.g., respirators and gloves worn by firefighters).
As an agency involved in high-risk activities, NASA is responsible for astronaut candidate selection and training, resource allocation, risk and research prioritization, determining mission feasibility (taking into account available resources and technological capabilities), and deciding whether associated risks to astronauts, crews, and programs are acceptable. Like other analogous high-risk professions, spaceflight involves sub-
stantial risk to the short- and long-term health of individuals during ground-based training and during missions, due to numerous uncertain or uncontrollable variables. The space environment includes unique and sometimes unpredictable hazards, including prolonged isolation, reliance on a closed environment, limited basic resources, and high levels of radiation (IOM, 2001). These conditions can have profound and, sometimes, lasting effects on an astronaut’s physical, physiological, or psychological health, as described in Chapter 3. NASA actively engages astronauts during all phases of their training and work in issues regarding health and safety and provides regular updates related to risks associated with spaceflight (Behnken, 2013). Astronauts may choose not to participate in a specific mission, and this decision should have few, if any, repercussions for inclusion on future missions (Behnken, 2013).
Workplace Risk Management by OSHA and NASA
In 1970, the Occupational Safety and Health Act (OSH Act) was enacted to “ensure safe and healthful working conditions for every working man and woman in the nation insofar as practicable, [so] that no workers will suffer diminished health, functional capacity or life expectancy as a result of their work experience.”1 To implement this legislation, Congress mandated the creation of the Occupational Safety and Health Administration (OSHA) within the Department of Labor. OSHA promotes worker safety and health through multiple approaches, including the establishment and enforcement of health standards and regulations restricting workplace exposures and mandating exposure and health monitoring, training, and information dissemination. The OSH Act also created the National Institute for Occupational Safety and Health (NIOSH), which conducts research and makes practical recommendations to prevent worker injury, illness, and death (CDC, 2013).
OSHA regulations apply to many occupations including those in general industry, agriculture, maritime, and construction; however, OSHA regulations do not cover all workers. OSHA does not have oversight over self-employed persons, employees of state and local governments (unless covered through an OSHA-approved state plan, which operates under state jurisdiction), or other federal agencies that regulate worker safety under the authority of other federal laws (including work-
1The Occupational Safety and Health Act of 1970, P.L. 91-596 (December 29, 1970).
places in nuclear energy and weapons manufacture, mining, railroad, and aviation).
NASA is authorized by the National Aeronautics and Space Act of 1958 “to make, promulgate, issue, rescind, and amend rules and regulations governing the manner of its operations and the exercise of the powers vested in it by law”2 related to the planning, direction, and conduct of aeronautical and space activities.3 This effectively exempts NASA from OSHA regulations and authorizes the agency to use its own discretion for programmatic activities, including “health and medical policies and standards that ‘regulate’ aircrew and space flight crew selection, qualification, and health-related requirements in NASA research aircraft and spacecraft” (Williams, 2013). However, NASA follows OSHA regulations for its ground workforce (Williams, 2013). For example, NASA’s Johnson Space Center has qualified for OSHA’s Voluntary Protection Program Star Rating (NASA, 1999; DOL, 2014), reflecting compliance with OSHA standards and periodic audits. For spaceflight, NASA has developed its own safety and health standards, as discussed throughout this report (NASA, 2007, 2011). When not preparing for or actively participating in space missions, astronauts may be engaged in more traditional occupational roles at NASA such as program development, operations, and management, and OSHA regulations apply to them as to all other NASA employees.
It is important to note that—unlike OSHA and NIOSH where responsibilities for regulation and policy research are separate from enforcement activities—NASA is tasked with assessing, evaluating, developing, and enforcing standards and regulations related to the health of its active astronauts, among other obligations. As described in Chapter 1, NASA is tasked with studying the potential benefits and problems associated with aeronautical and space activities,4 which include risks to, or impacts on, human health. In this context, NASA functions may be more similar to those of the military in that research, regulatory development, and enforcement are all within the purview of the military.
251 U.S.C. 20113(a).
3The National Aeronautics and Space Act of 2010, P.L. 111-314 (December 18, 2010).
4The National Aeronautics and Space Act of 1958, P.L. 85-568 (July 29, 1958).
One mechanism by which to manage occupational risk includes health standards, which are subject to revision based on new scientific data and require ongoing assessment. As discussed in Chapter 2, health standards may be used to protect workers; guide design, research, and engineering activities; stimulate innovation; serve as criteria for job requirements; and provide a condition for collaborative efforts. For example, some standards are relevant to worker selection or assessment of ongoing fitness for the job, which may involve periodic health monitoring. Other health standards protect against exposure to harmful physical agents or work environments during the course of employment and are intended to provide both immediate protection against acute injury and lifetime protection against harm. Health standards may be mandatory (e.g., OSHA standards) or voluntary, although often accompanied by significant incentives for compliance (e.g., the National Fire Protection Association’s [NFPA’s] standards5 or OSHA’s meatpacking guidelines).
NASA’s health standards were developed to promote “a healthy and safe environment for crewmembers, and to provide health and medical programs for crewmembers during all phases of space flight,” and include fitness-for-duty standards, space permissible exposure limits, and permissible outcome limits (NASA, 2007, p. 8). Although NASA’s health standards are unique to spaceflight, they are specific manifestations of workplace protections more generally provided for workers. Those protections reflect broader ethical and legal determinations concerning risk acceptance within the occupational domain. The following sections explore examples of fitness-for-duty standards and exposure limits in terrestrial settings.
Many high-risk occupations require both applicants and current members within a profession to meet specific fitness-for-duty standards, which typically assess “whether an individual is fit to perform his or her tasks without risk to self or others” (Serra et al., 2007, p. 304) and are based on the definition of essential job functions within a given profes-
5Some state OSHA rules may incorporate language from otherwise voluntary standards (e.g., NFPA standards), effectively mandating compliance (see, e.g., Alabama Municipal Insurance Corporation and Municipal Workers Compensation Fund, Inc., no date).
sion. For example, NFPA has set health standards that apply to both firefighter candidates as well as incumbents (i.e., current members within a profession) (NFPA, 2013a). Fitness-for-duty standards are also used by law enforcement (Quigley, 2008; Fischler et al., 2011), the military (NRC, 2006), and interstate truck drivers.6 In addition to physical standards, fitness-for-duty evaluations may also include psychological evaluations and mental capacity screenings, especially in jobs with high psychological demands, such as law enforcement (Fischler, 2011) and the military (NRC, 2006), including submarine crews (Kennedy and Zillmer, 2012).
The stringency with which medical and physical ability standards apply may differ for job candidates versus active members of a profession. For example, NFPA draws a distinction between health standards for candidates and incumbents, stating that the “intent with incumbents with a medical condition is to rehabilitate them and only restrict them from performing those essential job tasks where their injury or illness would affect the safety of themselves or others on their crew” (NFPA, 2013a, p. 1). The Air Force has a similar approach to fitness-for-duty standards applicable to current fighter and test pilots. In essence, the Air Force’s fitness-for-duty standards serve as a baseline for entry into a field with a waiver process to allow individuals to continue to work, if approved, with some medical conditions (U.S. Air Force, 2013).
Limiting Hazardous Exposures
A number of federal agencies set exposure standards or guidelines relevant to the hazards and occupations, including the Nuclear Regulatory Commission7 and Federal Aviation Administration,8 as well as NASA (NASA, 2007). OSHA sets workplace permissible exposure limits (PELs) for a variety of chemicals and other hazards. For example, OSHA’s lead standard limits the conditions under which an individual is allowed to work when lead is present in the work environment. OSHA’s PEL for lead is 50 micrograms per cubic meter of air as an 8-hour, time-weighted average.9 If an employee’s lead exposure exceeds the established PEL more than 30 days per year, the employer is required to im-
649 C.F.R. 391.41.
7See, e.g., 10 C.F.R. 20, Subparts C and D.
8See, e.g., 14 C.F.R. 25.832.
929 C.F.R. 1910.1025(c)(1).
plement engineering and work practice controls (including administrative controls) to meet the exposure level, factoring in feasibility.10 Respirators must be used to supplement engineering and work-practice controls when these are insufficient to reduce exposure below the PEL.11 The standard also requires employers to continually monitor employee exposures when baseline levels are exceeded and notify employees about excessive risk exposures and subsequent corrective actions.
Health standards may also require specific employer or employee action based on individual clinical observations if poor health outcomes may be linked to specific occupational exposures. For example, OSHA’s hearing protection standard states that if required audiograms show a “standard threshold shift” in hearing potentially related to occupational noise exposure, the employer must provide hearing protectors even if the noise exposure is within required limits.12
Federal agencies may also have significant latitude in determining what health standards are necessary to address a specific risk or hazard. For example, OSHA’s occupational and health standards must be “reasonably necessary or appropriate to provide safe or healthful employment and places of employment.”13 The U.S. Supreme Court has held that “reasonably necessary” requires OSHA to demonstrate a “significant” risk to employees that can be eliminated or lessened by a change in practices, with two important qualifications. First, OSHA is not required to establish a “significant risk” with scientific certainty.14 Instead, the agency can regulate on the basis of the best available evidence.15 Second, OSHA is responsible for determining what constitutes a “significant risk.”16 In its review of OSHA’s benzene standard, the U.S. Supreme Court characterized broad dimensions of significant risk in terms of acceptable and unacceptable risk, stating that, for carcinogens, a reasonable person would find a fatality risk between 1/1,000 (“plainly unacceptable”) and 1/1,000,000,000 (“plainly acceptable”) over a working lifetime to be significant. 17 The wide range between “acceptable” and “unac-
1029 C.F.R. 1910.1024(e)(1)(i). In these cases, the employer must reduce exposures to the lowest feasible level and must comply with additional respiratory protection requirements.
1129 C.F.R. 1910.1025(f)(1)(ii).
1229 C.F.R. 1910.95(j)(3).
1329 U.S.C. 652(8).
14Industrial Union Dep’t v. American Petroleum Institute, 448 U.S. 607, 656 (1980).
1529 U.S.C. 655(6)(b)(5).
16Industrial Union Dep’t v. American Petroleum Institute, 448 U.S. 607, 655 (1980).
1729 U.S.C. 655(6)(b)(5).
ceptable” risk, as defined by the U.S. Supreme Court, leaves ample room for philosophical debate. Although health standards are generally set based upon reasonably mature scientific knowledge, establishing health standards may be challenging in the context of a high degree of risk uncertainty.
Monitoring and Surveillance Programs
The threat of harm from specific exposures may trigger specific monitoring and surveillance efforts. In some cases, the federal government has committed to long-term research to better understand the risks of certain workplace exposures and to provide long-term screening for possible adverse health effects. During the Deepwater Horizon oil spill in 2010, clean-up workers were exposed to various hazards including oil, particulates, and oil dispersants (IOM, 2010). The National Institute of Environmental Health Sciences initiated the Gulf Long-term Follow-up Study (GuLF STUDY) to collect and analyze data to determine both acute and long-term physical and mental health effects of nearly 33,000 participants related to the Deepwater Horizon oil spill (NIEHS, 2014a). The GuLF STUDY “collected questionnaire data about oil-spill clean-up related exposures, health at the time of the spill and at enrollment, and lifestyle and other factors that might confound associations between exposures and health” (NIEHS, 2014b). Biological samples were collected for future research; and clinical measurements, including measures of pulmonary function, were made. Some participants may submit to more comprehensive clinical exams, and cancer and mortality records are linked to state cancer registries and mortality records (NIEHS, 2014b).
Similarly, the Federal Coal Mine Health and Safety Act of 1969,18 as amended by the Federal Mine Safety and Health Act of 1977,19 required NIOSH to jointly administer a program for early detection and prevention of coal worker’s pneumoconiosis with the Mine Safety and Health Administration (CDC, 2014). The resulting Coal Workers’ Health Surveillance Program includes the Coal Workers’ X-ray Surveillance Program, requiring operators of underground coal mines to provide chest x-rays to new miners “as part of a pre-placement physical examination or within
18The Federal Coal Mine Health and Safety Act of 1969. P.L. 91-173 (December 30, 1969).
19The Federal Mine Safety and Health Amendments Act of 1977. P.L. 95-164 (November 9, 1977).
six months after being hired” and then 3 years later to screen for pneumoconiosis (CDC, 2014). The program also requires operators to offer chest x-rays approximately every 5 years to all underground coal miners (CDC, 2014). If “black lung” disease is confirmed, then individuals in environments where dust concentration is more than 1.0 milligram per cubic meter of air may transfer to a mine where the dust concentration falls below this cutoff and have their exposures monitored frequently (CDC, 2014).
Other Duties and Responsibilities
In addition to health standards and surveillance or monitoring programs, other employer and societal responsibilities may apply. The U.S. workers’ compensation statutes aim to assist individuals who are injured or sickened on the job. The general purpose of such funds are to replace lost wages, cover medical expenses associated with on-the-job injuries, and provide vocational rehabilitation if a worker cannot return to a previous position due to an occupational illness or injury (Guyton, 1999).
For some high-risk public service occupations, the risks taken on behalf of society provide justification for long-term commitments to promote and protect the health of individuals within specific high-risk professions. For example, long-term health care benefits are available for all individuals who have served in the active military (VA, 2014a). Through the Veterans Health Administration, the Department of Veterans Affairs serves more than 8.7 million veterans each year (VA, 2014b) and provides “inpatient hospital care, outpatient care, laboratory services, pharmaceutical dispensing, rehabilitation for a variety of disabilities and conditions, mental health counseling, and custodial care” (CBO, 2007, p. 1).
RISK MANAGEMENT IN RESEARCH WITH HUMAN PARTICIPANTS
After a series of highly visible abuses in human research during the past century, governments and society established regulations to protect individuals who participate in research. The U.S. Office for Human Research Protections defines “research” as “a systematic investigation, including research development, testing, and evaluation, designed to
develop or contribute to generalizable knowledge.” 20 Biomedical research is often the focus of scrutiny because it can pose significant risk to the health and well-being of research participants and “its findings can have important implications for health” (IOM, 2002a, p. 17). The moral and social purposes of research regulations and policies are to guide judgments about when risks to an individual are low enough to justify inclusion in research protocols that may cause harm to the individual for the benefit of society, especially if there is no direct benefit to the individual participant. Moreover, the regulations promote distribution of potential benefits to individuals who chose to participate in research (or at least to the groups from which participants are recruited) and encourage trust from policy makers and the public by ensuring ethical research practices.
Biomedical research that is conducted to further the role of human beings in space exploration has been part of the space program since the outset. Astronauts serve a wide array of research capacities, including investigator, research coordinator, study team member, and finally study participant. In some cases, astronauts serve as the principal investigator for the research but, in other cases, astronauts contribute as study team members or inflight research coordinators to carry out medical experiments and collect data at the direction of an on-ground principal investigator. Astronauts also have the option of serving as research study participants, allowing their biomedical information to be collected, deidentified, and analyzed for research purposes.
Within the context of research, NASA as a government agency also plays multiple roles. It funds and supplies resources (such as equipment and labs in space) to facilitate research, provides mandatory oversight to ensure compliance with all applicable regulations, and plays a role in researcher and participant selection. As described in Chapter 2, NASA’s Human Research Program focuses on research in physiology, environment, and technology to better understand the risks and opportunities associated with human spaceflight (NASA, 2014).
2045 C.F.R. 46.102(d).
Regulations for Research Involving Human Participants
Although the committee was not tasked with establishing an ethics framework to govern astronauts as research participants in space,21 federal regulations governing human participation in research provide some of the best understood and accepted examples of ethics principles that govern risk exposures to individuals. Building upon key documents describing ethical research conduct,22 the U.S. Department of Health and Human Services has adopted extensive regulations that govern federally supported or conducted research involving human participants.23
Independent oversight is an essential component of ethical research involving human participants. Under the Common Rule,24 any research protocol involving humans must be submitted to an institutional review board (IRB), which is an administrative committee formally designated to review, approve, and potentially modify research involving humans (HHS, 1993). IRBs serve as the principal representatives of the interests of potential research participants (IOM, 2002b), functioning independently of, but in coordination with, other research-related entities (HHS, 1993). IRBs oversee not only the initial approval of a research protocol, but are also responsible for continuing review of ongoing research.25
As a general rule in research, as risks to individual research participants increase, so do the necessary levels of review, oversight, and the requisite, potential benefits. The Common Rule states that research may be approved only if risks to participants are minimized, if the risks of participation in a specific research protocol are reasonable in relation to the anticipated benefits and “the importance of the knowledge that may reasonably be expected to result.”26 Additionally, IRBs may only approve research protocols that include equitable selection of participants, safeguard and document informed consent and voluntariness of participation, provide adequate provisions for monitoring data collection to ensure
21In general, NASA medical data are not considered research data and may be used to update existing health standards (Williams, 2013).
22For example, The Belmont Report (DHEW, 1979), The Nuremberg Code (Nuremburg Military Tribunal, 1949), federal policy for the Protection of Human Subjects (45 C.F.R. 46.101-124), and The Declaration of Helsinki (WMA, 1964).
2345 C.F.R. 46.101-409.
24“The Common Rule” applies to all federally funded research involving human research participants and provides general guidance about levels of acceptable risk in light of potential benefits, participant selection, and informed consent (45 C.F.R. 46.101-124).
2545 C.F.R. 46.109.
2645 C.F.R. 46.111(a)(1) and (2).
participant safety, and ensure adequate protections of participant privacy and data confidentiality.27
Specific types of high-risk research may require continuous monitoring and review of study data to protect participant health and safety. For example, the National Institutes of Health (NIH) requires Data and Safety Monitoring Boards (DSMBs) for multisite trials that involve potentially risky interactions (NIH, 1998). Within NIH, the primary responsibilities of a DSMB include evaluation of monitoring systems for data to maintain participant safety; ensure data validity and integrity; evaluate study progress; and issue recommendations about the continuation or termination of a trial (NIH, 1998). DSMBs may terminate studies early if results indicate a clear risk or benefit to the study participants (NIDCR, 2014).
Even if an IRB and institution approve the levels of risk included in a specific research protocol, potential human research participants do not need to accept those risks. With few exceptions, “no investigator may involve a human being as a subject in research … unless the investigator has obtained the legally effective informed consent of the subject or the subject’s legally authorized representative.”28 Proper informed consent involves sufficient opportunity to consider the risks and benefits of the research and should “minimize the possibility of coercion or undue influence.”29Among other requirements, basic elements of informed consent include a written explanation of the purpose, procedures, and expected risks and benefits of the research, as well as a description of how confidential records will be protected. For research involving more than minimal risk, researchers are required to explain whether any compensation or medical follow-up are available if any harm occurs.30
RISK MANAGEMENT IN UNFAMILIAR ENVIRONMENTS
As described briefly in Chapter 1, exploration often involves the quest for information or resources in unfamiliar environments, and can lead to innovations and discoveries in many fields. Human presence in unfamiliar environments is often accompanied by risks. For purposes of this study, one of the more relevant examples of exploration in unfamil-
2745 C.F.R. 46.111.
2845 C.F.R. 46.116. IRBs may waive the informed consent requirement under certain conditions, per 45 C.F.R. 46.117(c).
2945 C.F.R. 46.116.
3045 C.F.R. 46.116(a)(6).
iar environments includes deep sea diving, which includes commercial, scientific, and recreational operations. Like astronauts, divers are exposed to a variety of health hazards, such as asphyxiation, respiratory and circulatory problems, hypothermia, and physical injury. Some of the more serious risks to human health arise from physiological changes within the body when exposed to high or changing ambient pressure (OSHA, 2014b). For example, the partial pressure of nitrogen in tissues can lead to nitrogen narcosis, affecting a diver’s judgment while submerged (OSHA, 2014a). Analogous to space exploration, risks associated with deep sea diving are affected by the number and length of missions (i.e., dives), environmental conditions (e.g., temperature and visibility of the water), and the nature of the tasks involved.
Different regulations apply to different classes of divers. OSHA regulations apply to commercial diving and focus on personnel requirements, general operation procedures, specific operations procedures, equipment procedures and requirements, and recordkeeping requirements. 31 Although the regulations themselves offer some evidence of prevailing social norms that influence health standard applicability, four exceptions to OSHA’s commercial diving standards may also be instructive. First, the purpose of specific diving activities is important. OSHA’s commercial diving standards do not apply to operations “performed solely for instructional purposes[,]”32 if the diver does not exceed certain depth thresholds and uses specific equipment.33 In justifying its rationale, OSHA explained that, unlike commercial divers, scuba diving instructors can choose their diving locations and environmental conditions (OSHA, 1977). The standards also include an exception for scientific diving (OSHA, 1982),34 which is based on a similar rationale, but further cites voluntary compliance with “well-established, consensus standards of safe practice” within the educational/scientific diving community (OSHA, 1982, p. 53357; see also, Lang, 2013).35
Second, commercial diving regulations do not apply to operations “performed solely for search, rescue, or related public safety purposes by
3129 C.F.R. 1910.410-440.
33Certain exclusions to the instructor exceptions apply when dives exceed specific diving ranges, include a particular diving mode, or specific equipment (OSHA, 1977).
3429 C.F.R. 1910.401(a)(2)(iv).
35For examples of consensus standards for scientific diving, see AAUS, 2013 and University National Oceanographic Laboratory System, 2009.
or under the control of a governmental agency.”36 This language reflects OSHA’s determination “that safety and health regulation of the police and related functions are best carried out by the individual States or their political subdivisions” (OSHA, 1977, p. 37655).
Third, diving operations governed by federal human research protections are also excluded.37 OSHA reasoned that human research participation is already subject to federal oversight designed to promote safety and health (OSHA, 1977). Moreover, OSHA’s final rule argues that the long-term safety and health of divers are best served by continued scientific research and continuous learning and improvement, which are designed “to extend the safe limits of diving physiology and technology” (OSHA, 1977, p. 37655).
Finally, OSHA includes an emergency exception to the commercial diving standards. Employers are allowed to deviate from the regulations if necessary “to prevent or minimize a situation which is likely to cause death, serious physical harm, or major environmental damage,” provided that certain administrative actions are taken.38Purely economic or property damages do not trigger the emergency provision (OSHA, 1977).
As discussed above, oversight for deep sea diving activities does not fall to the jurisdiction or financing of a single entity or agency. Although space exploration is becoming more of a commercial and international endeavor, a significant portion of the responsibilities, public investment, and varying levels of societal engagement and investment rests with NASA, as do the burdens of risk management decisions.
RISK MANAGEMENT IN HIGH-RISK ACTIVITIES
In many high-risk activities, the desire to protect something of perceived value may increase the threshold of acceptable risk in terrestrial settings. For example, society has justified high risks to the health and safety of firefighters and police officers during emergencies based on the desire to save lives and property, among other interests (see, for example, U.S. Army Combined Arms Center, 2010; Arizona Division of Emergency Management, 2012). In the military, operational objectives, such as special operations involving counterterrorism, may also justify
3629 C.F.R. 1910.401(a)(2)(ii).
3729 C.F.R. 1910.401(a)(2)(iii).
3829 CFR 1910.401(b).
high-risk activities (DoD, 2011). Similarly, the Federal Emergency Management Agency (FEMA) regulations allow a limited number of emergency workers to be exposed up to five times the amount of radiation expected during “all occupational exposures,” in order to avert the exposure of large populations to dangerous levels of radiation (FEMA, 2008, p. 54037). To prevent the development of catastrophic conditions that could significantly affect large numbers of people, the International Atomic Energy Agency (IAEA) has proposed a radiation exposure limit for emergency workers of 500 millisieverts (mSv), substantially larger than the 1-20 mSv range applied to routine operations and significantly larger than the 20-100 mSv limit for exposures to accidents that are not potentially catastrophic; even the 500 mSv value can be exceeded in the course of life saving actions, if the “expected benefits to others clearly outweigh the emergency worker’s own health risks” (IAEA, 2011, p. 93). Similarly, the U.S. Environmental Protection Agency (EPA) allows for increased radiation exposure to workers protecting large populations or property vital to the public welfare, provided that the exposure is unavoidable and appropriate actions have been taken to reduce the dose and monitor the effects of exposure (EPA, 2013).
The need for a well-trained workforce has also been used in terrestrial settings to justify increased health and safety risks in specific contexts. Realistic and often dangerous training may be used to prepare U.S. service members for operations (U.S. Coast Guard, 2013), although the military’s tolerance for risk during peacetime training missions is quite low. For example, the armed services do tolerate higher levels of risk in programs like Top Gun or Red Flag, which prepare individuals for combat deployments (U.S. Air Force, 2012). The proven benefits of realistic, high-risk training have led to its subsequent adoption by fire and police departments, including Live Fire Training (NFPA, 2013b; Feyst, 2014).
Finally, the need for technological and scientific advancement may also affect tolerated levels of risk. For example, many operational test flights, which exist to maintain the United States’ technological advantage (Allenby and Mattick, 2009), involve novel aviation feats, which increase the number and potential severity of known and unknown risks.
In many cases where federal regulations allow activities associated with high-risk exposures, such regulations also include a mandatory process for notifying individuals about those risks. In responses to radiological dispersal devices and improvised nuclear devices, FEMA requires that responders be “fully informed” of exposure risks that may occur and that risk acceptance be voluntary (FEMA, 2008, p. 45037). For doses
exceeding 50 REM, responders must be “fully aware” of acute and chronic cancer risks related to the exposure (FEMA, 2008, p. 45037). Similarly, the IAEA safety standards require that workers who volunteer for increased radiation exposures understand and accept the health risks associated with the exposure (IAEA, 2011). In the military, although pilots are expected to comply with orders to fly, the military might ask for volunteers on extremely dangerous missions, where the risk of fatality is very high (Cockerham and Cohen, 1981).
FACTORS AFFECTING DECISION MAKING ABOUT ACCEPTABLE LEVELS OF RISK
Decisions about what constitutes acceptable risk are highly contextual, and different people may interpret the same set of facts about risk differently. In its report Improving Risk Communication, the National Research Council (NRC) (1989) identified many factors that affect risk perception including familiarity with, and understanding of the risk; perceived control over a situation; severity and immediacy of the consequences; level of potential benefit; who the risk affects, including specific populations; dread; equity; media attention; and trust in institutions. All of these factors can influence the weighing of perceived or potential risk and benefit levels and, therefore, risk acceptance within the context of a specific activity.
The scope of socially acceptable risk and, therefore, permissible activities, reflects social values and norms for conduct that help distinguish between acceptable and unacceptable behavior. These values and norms seldom articulate specific ethics principles underlying societal preferences or limitations. Instead, they generally reflect a combination of non-normative variables like historical accident or political maneuvering, as well as normative factors like tacit moral judgments that may reflect common ethics principles.
Governmental regulations and oversight relevant to risk management decisions generally focus on fairly and justly protecting individuals from certain risks, especially when those risks are taken in exchange for some level of societal benefit. When society’s interests in protecting individuals from harm do not restrict individuals’ and institutions’ decisions to engage in specific high-risk activities, other responsibilities may emerge. When taken piecemeal, the previous examples may seem like unrelated illustrations that offer no consistent patterns or guidance from which to
draw conclusions. However, when taken as a whole, the examples include some common ethical norms embedded within decisions about risk in terrestrial settings, which parallel many of the factors described by the NRC.
Factors Influencing Risk Assessment and Tolerance
No single, simple summary statement adequately describes our national willingness to accept risks or our commitment to reduce them. However, the committee identified a number of common factors that underlie decisions about risk across a wide range of oversight. This section examines some of these factors, including types and severity of risk; the presence of actual harm; types and distribution of potential risks and benefits; activity purpose; the nature of the relationship between individuals approving, and those subject to, risk; the presence of independent oversight; and feasibility. This list of factors is merely illustrative and is not meant to represent an exhaustive list of factors that may influence risk assessment and tolerance.
Type and Severity of Risk
Societal tolerance for risk of harm to an individual typically reflects moral judgments about the probability of an adverse event occurring and the severity of a specific harm or resulting loss. For example, the OSH Act requires employers to provide, to the extent practicable, workplaces free of recognized hazards, assuring that employees do not suffer material impairment of health as a result of their lifetime of exposures to toxic agents or hazardous conditions at work. Permissible exposure limits are established to limit risk to individual workers, thereby maintaining the health of the working population and the functionality of society. Unknown environmental conditions, as described in the deep sea diving example, can increase risks to individual workers and participants, which may trigger increased governmental regulation of risk acceptance within those fields.
Presence of Actual Harm
When actual harms to individuals do occur in the context of high-risk activities, social morals may dictate follow-up actions. For example, workers’ compensation programs are designed to protect workers from
the negative impacts of actual injury or illness resulting from job-related activities. In rare cases, including exposures to hazards during the Deepwater Horizon oil spill cleanup, the threat of actual harm led to additional research and monitoring responsibilities on behalf of the government (NIEHS, 2014b).
Potential Risks and Benefits and Their Distribution
Specific classes of potential benefits trigger higher levels of societal risk acceptance. As described in the context of law enforcement and first responders, serious threats to life and, to a lesser extent, property will often justify increased risk exposures to individuals. Similarly, threats to national security also justify participation in activities that carry serious risks of mortality and morbidity. The need for a well-trained workforce and technological and scientific advancement are also commonly used to justify increased risk to individuals engaged in high-risk activities.
In addition to the class of benefit, the number of individuals who may receive a potential benefit (or avoidance of harm) also plays a role in risk acceptability. For example, the IAEA allows for greater radiation exposure for workers in emergency situations to prevent severe outcomes, including loss of life and catastrophic conditions with significant impacts on humans and the environment (IAEA, 2011). The protection of large populations also justifies increased radiation exposures under EPA regulations (EPA, 2013). The equitable distribution of risk and benefit also affects regulations governing clinical research involving humans.39
In general, society appears to be more willing to impose limits on risks within the same environment if the risks are related to conditions of employment. Consider the example of commercial deep sea diving. Although commercial diving operations may occur under conditions similar to deep sea diving for recreational or instructional purposes, governmental regulation is more robust in the context of commercial diving. Similarly, federally supported research involving humans immediately triggers review of risks to individual research participants. These decisions seem to embody the societal perception that workers and research participants deserve or require additional legal protections to regulate
3945 C.F.R. 46.111.
how decisions about risk acceptance are made. Although similar to potential benefits, activity purpose is distinct. Potential benefits are typically balanced against potential risks or harms to determine risk acceptability; whereas, activity purpose may be used to broadly encompass an activity within the scope of governmental regulation.
Presence of Independent Oversight
Society may accept additional levels of risks to an individual’s health and safety if objective, independent review bodies are in place to protect that individual’s interests. As described above, in research involving human participants, IRBs provide independent oversight to ensure that all research protocols do not present excessive risks to individual participants, and that individuals voluntarily consent to participate in research. The Common Rule may allow a potentially high-risk research protocol if a DSMB exists to detect evidence of harms to patient health and safety early on and throughout the study. Similarly, an independent oversight body typically reviews and must approve operational test flights before an individual pilot can consent to high-risk activities.
Independent oversight may also take the form of either an external or internal advisory body, which is not responsible for ultimate decision making. For example, federal advisory committees “provide advice that is relevant, objective, and open to the public” across a broad range of issues and topics covered by federal policies and programs (GSA, 2013). The distinction between an independent body that serves as an ultimate decision maker versus a body that serves in an advisory role is critical, and the committee was cognizant of this distinction as it considered the ethics governing decisions about health standards for long duration and exploration spaceflights.
Nature of the Relationship Between Individuals
The nature of the relationship between individuals affects the creation and scope of the duties incumbent on professionals, which influence the responsibilities to mitigate risk of harm and the risk levels that society deems acceptable. U.S. statutory and common law creates affirmative duties of care to prevent unreasonable loss or harm to others through an overt act or omission. The duty of care, which often includes actions to mitigate or limit risk, may arise from “special relationships,” including relationships between employers and employees, ones who assume con-
trol or custody of another,40 or if a fiduciary duty exists (Easterbrook and Fischel, 1993). Other examples of special relationships include the doctor-patient relationship (ACP, 2012) and attorney-client relationship (Small, 2009). In occupational health, concerns about coercion may stem from real and perceived power imbalances between employers and employees (Hogbin, 2006). Similar concerns about power imbalance, as well as information assymmetries and patient confidentiality, exist between doctors and patients (ACP, 2012). Individual employees may be willing to tolerate unsafe or hazardous conditions due to limited alternative employment options, concerns about job security, incomplete information about relevant risks, and lack of control over the working environment. Conversely, employers select their employees, set wages, create and oversee working conditions, assign work and determine work pace, evaluate employees, and initiate employee termination. Similar concerns about coercion and undue influence exist in research involving human participants.
Decisions about acceptable levels of risk are often impacted by considerations of the feasibility of reducing hazardous exposures. In some cases, feasibility limits are employed in an effort to drive acceptable risk to the lowest level possible. For example under several environmental health statutes the paradigm is to set the allowable limits as low as feasible, even if the risks become vanishingly small. The OSH Act’s use of feasibility allows higher risk than more conservative applications of feasibility. The OSH Act authorizes standards for exposure to workplace hazards that will ensure “no employee will suffer material impairment of health or functional capacity” but only “to the extent feasible.”41 Federal courts have interpreted “feasibility” to include both technical and economic feasibility in the context of OSHA rulemaking, but OSHA is not required to balance the cost and benefits of a proposed rule.42 Other regulatory agencies may select exposure levels that are “as low as reasonably achievable,” for example, to ensure that specific exposures are “as far below the dose limits as practical, consistent with the purpose for which the licensed activity is undertaken, taking into account the state of technol-
40Restatement (Second) of Torts §§ 314A, 314B, and 320 (1965).
4129 U.S.C. 655(6)(b)(5).
42ATMI v. Donovan, 452 U.S. 490 (1981).
ogy, the economics of improvements in relation to state of technology, the economics of improvements in relation to benefits to the public health and safety, and other societal and socioeconomic considerations.”43
In its task to look for analogs and models of how other occupations and efforts deal with uncertain health risks and risk management decisions, the committee found a lack of explicit frameworks but a variety of examples from terrestrial settings that inform deliberations about health standards for long duration and exploration spaceflights. Many of the efforts are focused on avoiding harm to workers and others who are willing to take risks to protect society. Both the context of the risk and the extent to which government, employers, or others are involved also affect the nature of the responsibilities and risk management approaches. Moreover, these factors implicitly embody ethics principles relevant to NASA decision making and provide valuable insights about considerations when designing an ethics framework to guide decision making about health standards for long duration and exploration spaceflights.
Finally, it is important to emphasize that space travel—with almost predictable certainty—will be fatal in some cases. Even so, the United States has continued to engage in human space travel for more than half a century. As described in Chapter 1, it is not within the charge of this committee to opine on the ultimate justification for human spaceflight. However the committee recognized that astronauts have volunteered, and are likely to continue to volunteer, for missions despite the uncertainty concerning the risks they will face. The committee kept this in mind as it considered ethics principles, responsibilities, and decision frameworks that are relevant to decisions about health standards for human spaceflight in Chapters 5 and 6.
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