What is Risk Assessment in Aviation SMS
Airport SMS programs and Airline SMS programs need to develop and maintain a formal process of risk analysis, risk assessment, and risk control to an acceptable level of safety (ALoS). We say that the process needs to be formal in the sense that risk assessments/analysis needs to be documented.
The risk assessment process in aviation SMS starts with hazard identification and hazard reporting. Once reported, aviation safety managers will assess the risk in terms of the following:
- Probability of negative outcomes; and
- Severity of most likely negative outcomes.
Probability and severity should take into account existing risk controls. Based on the probability and severity of the reported safety issue, safety managers will determine whether or not the safety issue falls within ALoS.
Usually, the probability and severity are each determined on a scale of 1 (low) to 5 (high) for probability, and A (low) to E (high) for severity. The aviation industry standard is to document the risk assessment results in a risk matrix. For a full details about risk matrix, refer to our article about what is a risk matrix and how to use it for risk assessments.
How to Perform Risk Assessment in Aviation SMS
A risk matrix is an excellent tool for quickly concluding the overall safety exposure resulting from a safety incident. Safety incidents can be real or an imagined scenario. Performing risk assessments follows a process similar to that of overall safety risk management, known as risk analysis process:
- Evaluate all hazards involved in the issue;
- Evaluate how well safety controls meet each hazard;
- Evaluate if a new control(s) is needed, and if so how severe the gap is;
- Based on elements involved, what is the severity and probability of negative outcomes in the future; and
- (if applicable) Implement needed changes (i.e. mitagative actions) to get the SMS program to an ALoS.
Again, it’s important to remember that risk assessments (number 4 above) are only one part of the risk analysis process, as risk analysis and risk assessments have different goals.
The result of performing a risk assessment will be a combination of one letter for severity and one number for probability.
Goals of Risk Assessments in Safety Risk Management
It’s important to understand the difference between risk assessment and risk analysis. The goals of risk assessment are to:
- NOT to make decisions; but
- Quantify safety events;
- Rank safety events;
- Determine overall exposure from safety issue;
- Document proof of performed risk analysis; and
- Track exposure.
Decisions should be made based off of risk analysis, which is the process of analyzing all factors involved in a safety issue. The reasons we use risk analysis rather than risk assessments to make decisions is that risk assessments:
- Give a 32,000 foot, macro overview of exposure; and
- Does not provide necessary details needed for making safety decisions.
Risk analysis DOES provide those details. However, in order to determine whether or not the risk is acceptable, safety managers should use the final risk assessment number/letter to determine whether the issue is in the “green” acceptable range.
Risk Management Tools to Aid in Assessing Risk
Many aviation risk management tools can be used to inform quality risk assessments. Some tools and similar risk management tools that we highly advocate for understanding risk exposure are:
- Bowtie analysis;
- Fishbone diagrams;
- Hazard Risk Register;
- Aviation safety database; and
- Aviation leading indicators.
Having a combination of the above points will significantly aid in assessing risk in terms of:
- Quality/accuracy of risk assessments;
- Efficiency of determining risk assessments; and
- Ability to make quality safety decisions based on risk analysis process.
Final Thought: Satisfying Risk Assessment Element of 4 Pillars
The risk assessment part of Safety Risk Management in the 4 pillars is satisfied when:
- There is a structured process for risk analysis that is consistent;
- Documentable evidence that reported safety issues are analyzed and assessed;
- Documentable actions that mitigative actions (see step 5 in risk analysis process above) are implemented based on risk analysis;
- Risk assessments are appropriately justified;
- Over time, risk assessments demonstrate a continuous improvement in safety exposure (increase in “green” assessments, and decrease in “yellow” and “red” assessments).