A risk is a circumstance or factor that may have a negative impact on the operation or profitability of a given operation. A risk can be the result of internal conditions, as well as some external factors related to the operations. An anomaly is an uncontrollable event. Despite all planning and preparation, anomalies can still occur. An anomaly is the the quality or state of being irregular.Usually a baseline of normal behavior or risks is recognized and when an event falls outside that norm, it is anomaly. Analysis of anomalies that occur during operations is an important means of improving the quality of current and future operations.
Both risk and anomalies cause changes to documentation and to operational procedures to prevent the same situations from recurring. For example in case of challenger case study there were many risks involved one of them was using the solid rocket busters which, once ignited could not be easily controlled or shutdown unlike the liquid rocket booster. This would be considered as a risk because this has been identified from the previous experiences and can have a contingency plan.
On the other hand an anomaly that affected the challenger case study was the unusual low temperature and ice present on the day of the launch. The project manager and the risk management team define risks affecting a project. The quality control and assurance team report operational anomalies to the project manager. Hence the project manager must decide the difference on what becomes a risk to the project and what stays as an anomaly.Engineers, safety officers define anomaly or people with deep knowledge of the subject matter define it.
Anomalies are defined and negotiated depending upon the occupational context and the evaluation systems that have been developed to meet unexpected deviations in the work flow. A mistake or anomaly is never defined in isolation, but always is relative to the local and institutional context of work.