occur. (Often informally referred to as likelihood or chance. See Likelihood for distinction in usage between likelihood and probability). Impact (or Consequence) The effect or outcome of an event affecting objectives, which may be expressed, by terms including, although not limited to health, safety, reliability, economic and/or environmental damage. Mitigation Measure or activity proposed or in process designed to reduce the impact/consequences and/or likelihood/probability of an event. Outcome The resolution or end result Risk Driver Factor(s) that could cause one or more risks to occur (Risk driver may also be commonly referred to as “threat”). Risk Response Plan Collection of mitigations Control Currently established measure that is modifying risk Alternative Analysis Evaluation of different alternatives available to mitigate risk Residual Risk Risk remaining after current controls. Planned or Forecasted Residual Risk Risk remaining after implementation of proposed mitigations. Risk Numerical representation of qualitative and/or quantitative risk assessment that is typically used to relatively rank risks and may change over time. Risk Tolerance Maximum amount of residual risk that an entity or its stakeholders are willing to accept after application of risk control or mitigation. Risk tolerance can be influenced by legal or regulatory requirements. Parties’ Comments Both the Joint Utilities and CUE agree with the proposed Working Group Lexicon, and the two proposed changes proposed in the SED Staff Report.
methods. It uses subject matter expertise that has been calibrated to fit its risk analyses and validates that expertise through supporting data. Similar to SCE, Sempra has mapped its risk management steps to the Cycla 10step process. Sempra’s risk evaluation tool is also referred to as RET, but it, too, is different from PG&E’s formula. Sempra’s RET formula is stated as: In this formula, impact is a logarithmscale whole integer (1 to 7) index score of consequence. Frequency follows a linear scale and is not modified by a logarithmic function. Sempra’s model chooses a fixed point from each of the seven logscale ranges of frequency to represent a frequency within a frequency range. Sempra’s risk model has four impact dimensions: Health, Safety & Environmental; Operational and Reliability; Regulatory, Legal & Compliance; and Financial. For convenience, we refer to these four broad categories by abbreviating them to safety, reliability, compliance, and financial. The safety impact dimension score receives a 40% weight. The remaining reliability, compliance, and financial impact scores each receive a 20% weight. Whereas PG&E and SCE have distinct impact dimensions for safety and environment, Sempra a different approach by putting any impact touching “health, safety, and environment” under an overarching Safety dimension. Therefore, Sempra’s definition for the safety dimension is more inclusive but less
Representative Shape of a Typical FN Curve A mathematical property of FN curves is that they are either flat or sloping downward as N increases but never upward sloping. An FN curve is typically shown on graphing paper with logarithmic scales on both the vertical and horizontal axes. An FN curve can be either derived from empirical accident data or represented by probabilistic models, which in turn are usually based on empirical data. Since an FN curve represents the potential physical risk to society at a fixed point in time, an FN curve can change shape or shift based on any circumstances that affect the calculation of risk. When an FN curve is constructed with the same units of measurement as an ALARP diagram, the two can be superimposed onto each other. (For more detail, see the ALARP White Paper.) FN Curve with ALARP Diagram Overlay Applicability In the U.S., the ALARP principle has been employed by the U.S. Army Corps of Engineers since 2009. The U.S. Nuclear Regulatory Commission has used a principle similar to ALARP since the 1950s to regulate exposures to radiation (where it goes by the name As Low As Reasonably Achievable, ALARA). In 1972 and 1977 the ALARA principle was adopted into two U.S. federal regulations (10 CFR 835 and 10 CFR 20) to regulate radiation exposures at Department of Energy and NRCregulated facilities.
As described in the Uniformity Report, the utilities currently assign LoF values to risky events using a 1 to 7 scale. The scale defines event frequencies or “arrival rates” as demonstrated below. As referred to in Section 5, the utility scales are similar to Richter scales, which are based on “order of magnitude.” According to Joint Intervenors, this 1 to 7 scale is “nonlinear” because the underlying “hazard rates” or frequencies represent changes in a way that are similar to order of magnitude differences. They observe, “Moreover, this scale means that an event occurring every 35 years has the same LoF (2) as an event occurring every 90 years, an event occurring every 3 years has the same LoF (4) as an event occurring every 9 years, and so forth, even though the mathematical probabilities of these events are different.” In essence, “the 1 to 7 LoF values do not correspond to mathematical probabilities.” 1 2 3 4 5 6 7 Remote Rare Infrequent Occasional Frequent Regular Common Once every 100+ years Once every 30100 years Once every 1030 years Once every 310 years Once every 13 years 110 per year >10 times per year Joint Intervenors also point out that the utilities do not use a consistent set of “weights” for each attribute. “Instead, it appears that the weights are set independently of the attribute ranges by individuals who did not specify the attribute ranges. Therefore, there is no reason to believe that either risk reduction will be measured correctly using such attribute weights.” Also, the utilities use “discrete” rather than “continuous” values in their scales. (If a scale
In other words, Joint Intervenors object to the presentation only of an “early stage” “risk mitigated to cost ratio” or related optimization. Instead, they suggest the following: Risk reduction calculations and risk mitigated to cost rankings need not be “pilot” or “early stage” calculations. Using [the] Joint Intervenors Approach or requirements based on that approach, the RAMP filing should provide risk reduction calculations that are comparable across the enterprise and use risk reduction per dollar spent to prioritize projects. Optimization should be implemented to the extent possible. Joint Intervenors also point out that the Joint Intervenors’ Approach would assist with the RAMP steps to “implement the probabilistic calculation in the shortterm” and “assist in the identification of data collection requirements.” Aside from the “Ten Components” matrix, Joint Intervenors strongly oppose the concept of an SED “Adoption Order” that would enable SED to formally adopt each utility’s RAMP filing and application prior to the GRC. Joint Intervenors objected to this proposal for two reasons. First, “Joint Intervenors oppose any process that purports to allow SED, or any unit of CPUC staff to issue an order that has binding effect or otherwise has the status of a Commission determination.” This would constitute an “improper delegation of the Commission’s authority” since major GRC issues generally require the higher level judgement of Commissioners. Second, Joint Intervenors also point out that the proposed “Adoption Order” is contrary to the direction of D.1412025 which directs the issuance of a single, final SED report before parties have an opportunity to ask questions or provide comments on it. “Issuing a report that has binding effect without even an opportunity for parties to be heard would be
SMAP decision.” In response to this statement, Joint Utilities reply, “SDG&E and SoCalGas appreciate Joint Intervenors’ understanding of the difficulties involved in putting together the firstever RAMP filing, and fully support the proposal above.” Discussion Consistent with the findings and recommendations in this decision so far, and parties’ comments regarding the RAMP process itself, it is appropriate to make the following changes highlighted in italics: Ten Components of RAMP Filings Recommended by SED (Modified) Step Description Overall, the utility should show how it will use its expertise and budget to improve its safety record. To do so, each utility should: The goal of the SMAP proceeding is to make California safer by identifying the mitigations that can optimize safety Identify its top risks Includes those risks ranked 4 or higher on the 7x7 matrices (Sempra only). Because the utilities may be moving away from the 17 scales for impact dimension and frequency, they should be poised to receive further direction pending the outcome of a Phase Two decision in this proceeding. Describe the controls or mitigations currently in place Creates a baseline for understanding how safety mitigation improves over time Present its plan for improving the mitigation of each risk Includes analysis of execution feasibility, affordability, and any constraints. Present two alternative mitigation that it considered D.1412025 calls for the presentation of two alternative plans. Present an early stage “risk mitigated to cost ratio” or related “risk reduction per dollar spent.” Pilot calculations are attempting to measure this item, although they are in an early stage (Sempra only) Depending on the outcome of the Two “test drive” of risk reduction calculations and risk mitigated to cost rankings, calculations