Today's customers expect nothing less than products of the highest quality, and it is incumbent on all manufacturers to assure this expectation is met. A proven technique for checking whether a manufacturing process is in control is a manufacturing audit.
A manufacturing audit is a comprehensive inspection of a process to determine whether it is performing satisfactorily. A manufacturing audit is usually limited to a small portion of units produced, but the manufacturing processes involved are reviewed thoroughly. An audit does not replace normal quality control efforts, but supplements them.
There are many reasons for conducting a manufacturing audit:
- Assures procedures reflect actual practice (what we say is what we do);
- Uncovers inaccuracies so they can be quickly corrected;
- Reveals the consistency of a process (from person to person, or day to day);
- Demonstrates a proactive approach to process improvement; and
- Encourages ongoing corrective action.
A good manufacturing audit requires:
- Announcement in advance. Manufacturing audits are not meant to catch people doing something wrong. On the contrary, during an audit you hope to catch people doing things right.
- A rating scheme to classify problems discovered. A rating scheme allows you to rank problems in order to prioritize corrective actions.
- Action when a problem is discovered. Nothing is more discouraging than discovering a problem and doing nothing about it. Ideally, employees working on the process should assist in the resolution of any problems found. This will increase employee sensitivity to the problem.
- Trained auditors. Auditors should be familiar with both the area they are observing and with auditing techniques.
- Planning and clear procedures. A manufacturing audit is more than just walking into a work area and looking for trouble.
Audits must be carefully planned and orchestrated for maximum benefit. The steps listed below can help in planning and conducting an audit.
- Select the process to audit. It may be best to begin with a relatively efficient process that has a history of success.However, you may prefer to jump right into a process that has had a record of ongoing performance problems.
- Decide who will conduct the audit. Ideally the audit team should be made up of individuals who have audit experience, but are also generally familiar with the process to be audited.
- Decide the frequency of the audit. It should be decided how often members of the audit team will observe the process.The more nonconformances discovered, the more frequent the observations until such a level of confidence is gained that the observations can be scaled back.
- Record the audit schedule on a form. Audit times should be as random as possible and scheduled throughout an entire shift. There should be a written record of this schedule that is distributed to each member of the audit team.
- Conduct the audit according to the audit schedule. Once you make the permanent schedule, it should be followed. This requires a commitment from everyone involved with the process.
- Document problems discovered. This becomes the permanent record and the basis for all follow-up actions.
- Inform all those affected (workers, other department personnel, and so on). Not only should the employees working in the process be informed of the audit results, but all employees affected by the performance of the process should be notified also. This will assure that everyone is aware of problems discovered and may generate additional suggestions for improvement.
- Determine corrective action. Once employees have had an opportunity to offer suggestions for resolving the problems, the most appropriate action should be selected.
- Perform corrective action. Implement the changes required to prevent repeat problems.
- Monitor corrective action results. Observe the corrective action to determine if it really eliminated the problem. Auditing is a proactive effort to assure that a manufacturing process is under control. Auditing also indicates a willingness to go beyond the status quo and commit to continuous improvement.