Rapid technological change, increasing scale of industrial complexes, increased system integration, market competition, and other factors have been shown to increase societal risk in the past few decades. As such, risk assessments become increasingly critical in mitigating accidents, improving safety, and improving outcomes. Risk assessment consists of an objective evaluation of risk in which assumptions and uncertainties are clearly considered and presented. This involves identification of risk (what can happen and why), the potential consequences, the probability of occurrence, the tolerability or acceptability of the risk, and ways to mitigate or reduce probability of the risk.Optimally, it also involves documentation of the risk assessment and its findings, implementation of mitigation methods, and review of the assessment (or risk management plan), coupled with updates when necessary.Sometimes risks can be deemed acceptable, meaning the risk "is understood and tolerated ... usually because the cost or difficulty of implementing an effective countermeasure for the associated vulnerability exceeds the expectation of loss