Why is a quantitative risk assessment (QRA) essential for evaluating the safety of a proposed modification to a natural gas processing facility?

A quantitative risk assessment (QRA) is essential for evaluating the safety of a proposed modification to a natural gas processing facility because it provides a numerical estimate of the potential risks associated with the modification, allowing for a more informed decision-making process. A QRA is a systematic process for identifying, analyzing, and evaluating risks. It involves quantifying the likelihood and consequences of potential hazardous events to determine the overall risk level. When a modification is proposed to a natural gas processing facility, it is important to assess the potential impact of the modification on the overall safety of the facility. A QRA can be used to identify new hazards that may be introduced by the modification, as well as to assess the potential impact of the modification on existing hazards. The QRA provides a numerical estimate of the risk, which can be compared to pre-defined risk acceptance criteria. This allows for a determination of whether the proposed modification is acceptable from a safety perspective. If the QRA indicates that the risk is too high, then additional safeguards or design changes may be necessary to reduce the risk to an acceptable level. Furthermore, a QRA can be used to compare different design options and to select the option that provides the lowest overall risk. By providing a quantitative assessment of the risks, a QRA helps to ensure that the proposed modification is implemented safely and that the overall safety of the facility is maintained or improved.