Each week I audit a different company, or I teach a group of students how to audit. In the courses I teach, I use a slide that gives an example of an internal auditing schedule (see the example above). On the surface, this example seems like a good audit schedule. There are 12 auditors performing two audits each year. If each auditor spends a day auditing, and another day writing the report, the combined resources equal 48 days (~$20,000) allocated to auditing, and each person spends less than two percent of their work year auditing.
Unfortunately, I have learned that the quality of auditing is directly related to how much time you spend auditing. Therefore, I recommend using fewer auditors. There is no perfect number, but “less is more.” My example also has another fundamental weakness. The internal auditing schedule does not take full advantage of the process approach to auditing. Instead of performing an independent audit of document control and training, these two clauses/procedures should be incorporated into every audit. The same is true of maintenance and calibration. Wherever maintenance and calibration are relevant, these clauses should be investigated as part of auditing that area.
For example, when the incoming inspection process is audited, it only makes sense to look for evidence of calibration for any devices used to perform measurements in that area. For a second example…when the production area is being audited, it only makes sense to audit maintenance of production equipment too.
If the concept of process auditing is fully implemented, the following ISO 13485 clauses can easily be audited in the regular course of reviewing other processes: 4.2.1), Quality System Documentation, 4.2.3), Document Control, 4.2.4), Record Control, 5.3), Quality Policy, 5.4.1), Quality Objectives, 6.2.2), Training, 6.3), Maintenance, 6.4), Work Environment, 7.1), Planning of Product Realization & Risk Management, 7.6), Calibration, 8.2.3), Monitoring & Measurement of Processes, 8.5.2), Corrective Action, and 8.5.3) Preventive Action. This strategy reduces the number of audits needed by more than half.
Internal Auditing: Upstream/Downstream Examples
Another way to embrace the process approach to auditing is to assign auditors to processes that are upstream or downstream in the product realization process from their own area. For example, Manufacturing can audit Customer Service to understand better how customer requirements are confirmed during the order confirmation process. This is an example of auditing upstream because Manufacturing receives the orders from Customer Service—often indirectly through an MRP system. Using this approach allows someone from Manufacturing to identify opportunities for miscommunication between the two departments. If Regulatory Affairs audits the engineering process, this is an example of auditing downstream. Regulatory Affairs is often defining the requirements for the Technical Files and Design History Files that Engineering creates. If someone from Regulatory Affairs audits these processes, the auditor will realize what aspects of technical documentation are poorly understood by Engineering, and quickly identify retraining opportunities.
One final aspect of the example internal auditing schedule that I think can be improved is the practice of auditing the same process twice per year. This practice doesn’t seem to work very well for a few reasons. First, it requires that an auditor prepare for an audit twice per year and write two reports, instead of one. This doubles the number of time auditors spends in preparation and follow-up activities associated with an audit. Second, increasing the number of audits naturally shortens the duration of each audit. It is more difficult for auditors to cover all the applicable clauses in a shorter audit because it takes time to locate records and pursue follow-up trails. Longer audits, covering more clauses, make it easier for the auditor to switch to a different clause while they are waiting for information. Third, if an area is audited every six months, it is often difficult to implement corrective actions and produce evidence of effectiveness before the area is due for auditing again.
I can’t provide a generic internal auditing schedule that will work for every company or even show how all the clauses will be addressed in one table. I can, however, provide an example of an improved schedule that illustrates the above concepts. This example (see below) uses four auditors instead of 12, and the number of days planned for each audit is two days instead of one. The preparation and reporting time is still one day per audit. Therefore the combined resources equal 24 days (~$10,000) allocated to auditing, and each person spends two and one-half percent of their work year auditing. My intention is not to create the perfect plan, but to give audit program managers some new ideas for more efficient utilization of resources. I hope this helps, and please share your own ideas as comments to this posting.