Risk perception

Risk perception is an important element that considerably affects the entire risk management process, including risk analysis and risk evaluation, and attitudes towards risks. Risk analysis, which is, in principal, a "pure" scientific and technical process, may not necessarily take into consideration socio-political and other related factors. Risk evaluation, on the other hand, in particular evaluation at high levels of decision-making, takes into consideration the wide range of interrelated factors, including public risk tolerance, costs/benefits trade-offs, socio- political and ethical factors.

The level of risks is generally determined the basis of scientific estimations and judgments, and by observations of what society at the present tolerates.

Whether risks are considered tolerable or not may often be judged by the decision-makers at higher levels. Their judgments will depend on whether they believe that there is extra public sensitivity about risks (HSC 1991). In many cases, risk evaluation may be a socio-political rather than a scientific matter (Kunreuther and Slovic 1996).

It is often difficult to judge precisely what may be acceptable and unacceptable in a particular country, industry, or sector of society. This is

because of the wide range of various interrelated factors. Judgments about the tolerability or acceptability of risks vary across countries, regions, industries, sectors, individuals, and societies, as do types of risks and experiences. Judgments also alter with time – what was acceptable yesterday may not be acceptable today and tomorrow. People’s views on risks and their value judgements are not static, but change according to circumstances (HSE 2001). Studies on risk perception have led to a theory which considers that it may be simplistic to believe that it will be possible to derive a quantifiable physical reality that most people will agree represents the ‘true’ risk from a hazard (HSE 2001). This theory maintains that the concept of risk is strongly shaped by human minds and cultures (HSE 2001).

The public risk tolerance is a function of different factors including risk perception, judgments, aversion, willingness and benefits. For example, a survey (ACS 1998) has shown that a sizable gap exists between risk experts and non-technical citizens or the general public over how to define, measure and evaluate risks. Risk experts and technical officials tend to focus on the standard concept of risk as the possibility of damage (ACS 1998). By contrast, the general public tends to expand the concept of risk to include other “non-damage” attributes (ACS 1998). They reflect societal values and the role of aversions and fears that hazards can cause. In the Netherlands, for example, attempts have been made to express risk aversion mathematically in the form of a risk aversion index, and to integrate it in the overall risk evaluation (Vrijling et al. 2004).

The following presents the results of several studies concerning attributes affecting risk perception, evaluation and attitudes towards risks, including risks of dangerous goods (Sprent 1988; FACN 1995):

• Voluntary/involuntary risks: Risks voluntarily assumed are ranked differently from those imposed by others. Involuntary risks, which may include risks of toxic fumes, spills, contaminations and fires/explosions, are regarded as worse than voluntary risks, such as risks of climbing, diving and driving.

• Uncontrollable: The inability to personally make a difference may decrease the acceptability level of risk.

• Immoral: Pollution is often viewed as a consummate evil; statements such as “hazards are too low to worry about” can cause suspicions.

• Familiarity/unfamiliarity: Generally, more familiar risks are regarded as more acceptable.

• Dreadful: Risks that cause highly feared or dreaded consequences are viewed as more dangerous.

• Uncertain: Scientific uncertainty about the effects, severity, or prevalence of a hazard tends to escalate unease.

• Catastrophic: Large-scale disasters weigh more seriously in the public’s mind than small-scale individual events. Society generally has a strong aversion to multiple casualty accidents (IMO 2004). A single accident that kills 1,000 people is perceived worse than 1,000 accidents that kill a single person (IMO 2004).

• Memorable: Risks embedded in remarkable events have greater impact than risks that arise in less prominent circumstances.

• Unfair: Substantial outrage is a more likely result if people feel they are being wrongfully exposed.

• Untrustworthy: The level of outrage is higher if the source of the risk is not trusted.

• Concentrated risks: Concentrated risks, in which dangerous goods risks may fall, are regarded as worse than diffused risks, such as for example risks of ordinary traffic accidents.

• Benefits, voluntary/involuntary risks: The public aversion is greater for involuntary risks involving activities with no immediate or little benefits than voluntary risks involving activities with immediate and large benefits. For example, risks to people living near roads, railroads, coastal zones, storages, terminals, ports and other facilities handling dangerous goods, with no or few direct benefits from the activities, are regarded as worse than risks to beneficiaries, such as employees (e.g.

workers, stevedores and carriers) who are directly involved and benefit, for example, from the transport of dangerous goods and related activities. According to Starr (1969), public tolerance may be as many as 1000 times higher for voluntary risks than for involuntary risks with the same benefits of activities (Vrijling et al. 2004).

• Immediate risks/consequences: People are generally more averse to risks with immediate consequences than to those with long delayed effects.

Risk perception also depends on types of risks to which people are exposed. For example, natural and technical or man-made risks may be perceived differently. Thus, natural risks, such as risks of earthquakes and flooding disasters, are generally considered as inevitable because people think that they have little, if any, control over these events and, therefore, they may consider such natural risks as “acceptable” risks. However, technical or man-made risks, in which risks of dangerous goods fall, may not be perceived and accepted in the same way as natural risks.

In summary, risk perception is an important multidimensional and dynamic factor that should be taken into account in understanding and dealing with risk issues, risk evaluation and risk management.