Preliminary Hazard Analysis vs. FMEA in Aligned Elements
From the very first day, we decided to integrate risk management into Aligned Elements. It is obvious to anyone within the industry that risk management and requirement-specification-verification-validation management are intimately connected. Still, many companies insist on keeping these two artefact collections separate in isolated systems. We think the management of all Design Control Items, including risk information, can be made more efficient with less errors if they are kept within one system.
Failuremode and Effect Analysis in Aligned Elements
In Aligned Elements, we initially implemented FMEA as risk analysis method. The FMEA is a very versatile risk assessment technique. It is widely adopted in the medical device industry and fairly straight forward to understand.
The implementation of FMEA:s in Aligned Elements goes as follows: a Failuremode entity holds a collection of Hazard entities. Each Hazard contains a cause with its probability, an effect with its severity, and an additional optional visibility parameter. A risk priority number is calculated based on the probability, severity and visibility values. The Hazard can then be addressed with one or more Mitigations which, each in turn, reduce the RPN to a new value.
All this entered risk information in subjected to Aligned Elements general features, including:
- Individual IDs assigned to each entity
- Strict version management of all changes made
- Changes are registered chronologically in the project audit trail
- Search and filter options can be applied using the Query Manager
- Risk reviews can be performed using the integrated Design Review Module
- The risk information can be included in the Aligned Elements DHF Index
Based on our experiences of time consuming risk analysis work, we included a number of usability features to make the day-to-day work easier and to save time and resources:
- Automatic calculation of RPN
- Automatic checks of RPN against thresholds
- Intelligent reuse of mitigations
- Highlighting of unmitigated risks
- Highlighting mitigations that have not been implemented
- Automatic Risk Summary generation
- Control checks that applicable parts of the DHF has been subjected to risk analysis
- Highlights which requirements/specifications/tests that are affected by the risk analysis
- Incorporation of risk entities into the overall trace landscape
One of the many reasons the FMEA is such a widely adopted technique derives from its versatility and flexibility. This permits the medical device manufacturer to apply the best possible fit between his risk analysis approach and his existing products, processes and organization.
Aligned Elements provides a number of customization possibilities to ensure that a wide range of FMEA variants can be applied, including:
- Customizable naming of the parameters and entities
- Customizable Probability, Severity and Visibility ranges
- Customizable thresholds for unacceptable risk, ALARP and acceptable risk
- Customizable formulas for RPN calculation
- Customizable look and feel of the risk report
- Expanded Risk reports to include traceability to mitigation implementation according to client QMS
- Multiple FMEA types in the same project
Enter Preliminary Hazard Analysis
Not all our customers favored the FMEA as risk analysis method. We therefore contacted ProSystem AG, an well renowned expert company in the area of medical device risk management and active member in several norm groups (such as IEC 62304, IEC 60601-1) and jointly developed a Preliminary Hazard Analysis (PHA) method in Aligned Elements as an effective complement to the existing FMEA method.
According to theory, the PHA is a top-down approach, using a list of known hazards as input for the risk analysis. The PHA method can be applied in the early stages of the development process and does not presuppose detailed knowledge about the system to be analyzed.
The Aligned Elements Preliminary Hazard Analysis uses a terminology aligned with ISO 14971 to describe Potential Hazards, Harms, Measure entities etc..
As opposed to the FMEA, our PHA implementation uses a stricter separation of Causes and Harms from the Risk Analysis aggregator (the Risk Analysis entity corresponds to the Failuremode entity as a collection of Causes and Harms under a particular subject), where Causes and Harms are captured as separate entities. This allows a more efficient reuse when causes and harms are reoccurring throughout the risk analysis, saving time when creating and managing the risks. Keeping the Causes in separate entities further permits them to be used as the link between IEC 62304 Software Items and the risk analysis in accordance with the IEC 62304.
In the PHA, we have expanded the Cause entity to include a “Cause source”-parameter to enable a more precise analysis of risk causing factors. Correspondingly, the Harm entity has an additional “Has Effect On”-parameter for a more granular designation of the affected agent.
Furthermore, in accordance with best practices from ISO 14971 and other risk norms, the Measure entity contains an additional parameter to explicitly designate risk control approach such as "Design for inherent safety", "Adding Protective measure", "Providing Information of Safety" etc. This risk control approach can further be connected to the risk reduction parameter controlling the new RPN to ensure that a given risk control approach always results in a consistent risk reduction.
With the Preliminary Hazard Analysis, we have created a capable complement to the existing FMEA risk analysis implementation. We have enlisted the help of renowned industry experts and used input from our client base to build an implementation more aligned with ISO 14971 and industry best practices. The decoupling of the PHA entities in separate Document Object types permits a more efficient information reuse than the FMEA implementation. Additional parameters enables the user for more in-depth analysis of risk drivers. This has been achieved without compromising the benefits of strict version control, integrated consistency checks and flexibility that Aligned Elements offers.
If you are interested in a demonstration of the Aligned Elements Preliminary Hazard Analysis, please contact us.