- 1-1 Engineering Ethics
- 1-2 Myths about Process Safety
- 1-3 Safety Culture
- 1-4 Individual Risk, Societal Risk, and Risk Populations
- 1-5 Voluntary and Involuntary Risk
- 1-6 Safety Metrics
- 1-7 Accident and Loss Statistics
- 1-8 Risk Perception
- 1-9 Risk Tolerance/Acceptance and Risk Matrix
- 1-10 Codes, Standards, and Regulations
- 1-11 Safeguards
- 1-12 The CCPS 20 Elements of Risk-Based Process Safety
- 1-13 Inherently Safer Design
- 1-14 The Worst Chemical Plant Tragedy: Bhopal, India, 1984<sup><a id="ch01fn13_r" href="ch01.xhtml#ch01fn13">13</a></sup>
- 1-15 Overview of Chemical Process Safety
- Suggested Reading
- Problems
1-4 Individual Risk, Societal Risk, and Risk Populations
Risk can be addressed from many different angles. With individual risk, one person is exposed to one or more hazards, as shown in Figure 1-2. Individual risk calculations are normally performed when considering a plant employee exposed to plant hazards. In contrast, with societal risk, a group of people is exposed to one or more hazards. Societal risk calculations are normally performed when considering the risks to a community surrounding a chemical plant and exposed to multiple plant hazards. Methods to calculate and display individual and societal risk are discussed in depth in Chapter 12, “Risk Assessment.”
Figure 1.2 Individual versus societal risk.
For every accident, there are potentially many people and different populations at risk—the so-called risk populations. For an incident in a chemical plant, for example, risk populations would include the workers in the plant, workers in adjacent plants, and the people living nearby in the surrounding community since they may be seriously affected by a plant incident. The plant and community will likely also suffer physical damage, leading to a financial impact. The company’s stockholders are also at risk since the company’s reputation will be negatively impacted and its stock value will decline. In addition, the insurance companies for the plant and the community will suffer losses and are another risk population. The entire chemical industry, in general, will be at risk as well, since its reputation will be diminished. Other risk populations are also possible.
The primary risk population can be defined as those who suffer immediate injury or death.