Risk-Based Decision Making

The use of the risk-based decision making process allows for efficient allocation of limited resources, such as time, money, regulatory oversight, and qualified professionals. Advantages of using tliis process include  

Decisions are based on reducing tlie risk of adverse human or emdronmental impacts 

Site assessment activities are focused on collecting only tliat iiifomiatioii that is necessary to make risk-based corrective action decisions 

Limited resources are focused on those sites tliat pose the greatest risk to hunian healtli and tlie eiivironment at any time 

Compliance can be evaluated relative to site-specific standards applied at site-specific point(s) of compliance 

---

Bohnenblust, H. and Slovic, P. 1998 Integrating Technical Analysis and Public Values in Risk-based Decision Making. Reliability Engineering and System Safety, 59, 151-159. 

Section 13.2 Qualitative Risk Scenarios Section 13.3 Quantitative Risk Non-carcinogens Section 13.4 Quantitative Risk Carcinogens Section 13.5 Risk Uncertainties/Liinitations Section 13.6 Risk-Based Decision Making Section 13.7 Public Perception of Risk... 

By using risk-based decision making, decisions are made in a consistent maimer. Protection of both human healtli and the enviromiient can be accounted for. ... 

Risk-based decision making and risk-based corrective action arc decision making processes for assessing and responding to a health hazard. The processes take into account effects on human healdi and the enviroiunent, inasmuch as chemical releases vaiy greatly in terms of complexity, physical and chemical characteristics, and in the risk that they may pose. Risk-based corrective action (RBCA) was initially designed by the American Society for Testing and Materials (ASTM) to assess petroleum releases, but tlie process may be tailored for use with any hazard. 

Risk Management Ecological Risk-Based Decision-Making Stahl, Bachman, Barton, Clark, deFur, Ells, Pittinger, Slimak, Wentsel, editors... 

In using any risk measure, it should be remembered that risk measures, at best, are only estimates of possible event frequency and consequences All risk measurements have uncertainties. In some situations, the uncertainties can be highly significant. The fact that risk measurement is imprecise should be a consideration in any risk-based decision-making process. Chapter 5 of Reference 4 provides further discussion of uncertainty in risk decision making. 

As a practical matter, risk reduction should always be considered before proceeding with QRA. If the cost of proposed risk-reduction measures is high, a detailed QRA may be justified. In this event, various risk-reduction options can be evaluated to determine which options produce the greatest benefit at the lowest cost. Additional guidance on risk-based decision making is available in the CCPS s Tools for Making Acute Risk Decisions with Chemical Process Apphcations (Ref. 77). 

As discussed in Chapter 4, some risk-based decision making can benefit by the development of tolerance criteria for the various types of risk to which building occupants may be exposed. When identified risks are higher than what can be deemed tolerable, they should be eliminated or reduced to control the company s risk exposure. The process of risk identification and evaluation, comparison to tolerance criteria, and elimination or reduction of intolerably high risk is known as risk management. Figure 6.1 illustrates this process. Application of these tolerance criteria helps protect building occupants and ensure that resources are appropriately applied. 

Deciding which risk-reduction method to use maybe difficult. In many instances, appropriate decisions can be made without resorting to quantitative techniques. However, in some cases, particularly when the options are costly, quantitative risk analysis (QRA) and risk-based decision-making approaches may be an effective basis for measuring the improvement in safety arising from the proposed options. These approaches can also be used in prioritizing safety improvements and balancing cost and production issues. 

Stahl RG Jr (2001) Introduction and background to the development of a framework for ecological risk management. In Ralph G, Stahl I et al (eds) Risk management ecological risk-based decision-making. SETAC Technical Publications Series, Pensacola, FL... 

This approach may sound pretty good, but it does not make much sense. The I can t find it, so it must be safe approach to controlling environmental risks is flawed because it depends upon the operation of a relationship between technical capabilities to detect the presence of a chemical and the magnitude of the health risks it poses. There is no such relationship. Further elaboration of this issue is in order, and a specific example will be useful, because it leads us into the heart of risk-based decision-making. 

Another approach to risk-based decision-making is the precautionary principle. The risk assessment and risk management approach used in the United States places a heavy reliance on the certainty of the data. The precautionary principle emphasizes that there is always some uncertainty and that decisions should be based on recognizing the possibility of harm. When in doubt, be cautious until adequate data are available to show that there is little potential for harm. Action to reduce exposure to hazardous agents should begin even if there is some uncertainty in the data. 

Moore DRJ, Sample BE, Suter GW, Parkhurst BR, Teed RS. 1999. Risk-based decision making the East Fork Poplar Creek case smdy. Environ Toxicol Chem 18 2954—2958. 

By using risk-based decision making, decisions are made in a consistent... 

Currently, there are a limited number of chemicals classified as male reproductive toxicants. As scientific, public, and regulatory interest in this field increases, the result will most certainly be an increased knowledge base of the type and number of chemicals that can adversely affect the male reproductive tract. Once a chemical is considered a potential reproductive toxicant, there are measures in place to protect humans from occupational and environmental exposure. For example, when the results from a risk assessment indicate that the potential exists for adverse reproductive effects in humans, a regulatory agency such as the US EPA may impose restrictions on the availability or uses of certain compounds. Reproductive toxicity testing is fundamental to this type of risk-based decision-making, and will hopefully lead to the development of safer chemicals and drugs. 

The data evaluation step in Tier 1 identifies the constituents of potential concern and the concentrations at which they occur in impacted media as determined by investigations conducted at the site. Most states do not require evaluation of historical data as part of the Tier 1 evaluation, although they may require submission of these data in the RBCA report as a basis for comparison (e.g., to demonstrate the decrease in constituent concentrations over time and/or demonstrate plume stability). However, the data that best represent the current environmental conditions at the site should be used in the risk-based decision-making approach. 

RBCA and the use of risk-based decision-making to establish health-protective remedial measures and controls at a site is a process that is producing health-protective and cost-effective corrective action sites. RBCA is used to decide the level of corrective action necessary at a site to protect human health and the environment, site-specific remediation goals (RBSLs or SSTLs), and the concentrations of constituents that can remain at the site because they will not impact human health and the environment. For sites already undergoing remediation, the RBSLs or SSTLs can be used to determine when the site no longer poses a threat to human health and the environment. Therefore, RBCA is useful both for newly discovered releases as well as for old releases that may have treatment systems with constituent concentrations reaching asymptotic levels. 

A White Paper published by the European Commission in February 2001 identified inadequacies in the current arrangements and proposed a new system for the registration, evaluation and authorisation of chemicals (REACH). The proposal will change the current procedures for submissions of risk assessments and is discussed later in this chapter. Risk-based decision-making thus has become... 

---