American Association for Laboratory Accreditation

Explanations for the ISO/IEC 17025 Requirements

This section presents A2LA's official explanations of the ISO/IEC 17025 requirements. It is expected that laboratories will implement the requirements of the standard in accordance with the explanations listed here. Otherwise, areas of non-conformance will be identified by the assessor during the on-site assessment. To have the latest updates delivered to you directly, please subscribe to the RSS feed below:.

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What is meant by a “root cause” investigation and how do I go about this?

Root cause analysis is the most challenging aspect of the corrective action process and should be used as a tool for continuous improvement, which may reduce or eliminate the likelihood of future deficiencies. Understanding why an event occurred is the key to developing effective corrective actions. In some cases, the root cause is singular and easily discerned; in most cases it is not, and there may be multiple root causes. Because of this, there is no single ‘recipe’ that can be followed. While it is impossible to create a procedure that would apply to all scenarios, there are some guiding principles which can be employed, the most important of which is that the root cause should address the question: “Why did this deficiency occur?” Other points to consider:

• Statements of root cause which are essentially a restatement of the deficiency provide no new information beyond the deficiency and are of little benefit to you and are not considered to be an acceptable response by A2LA. In these instances, the root cause is a result of the laboratory asking “why was this deficiency cited?” instead of “why did this deficiency occur?”

• Each deficiency must be evaluated independently.

• While each deficiency and its associated root cause must be approached individually, trends in the identified root causes for a group of deficiencies is a strong indicator that further investigation is needed. For example, upon conclusion of an assessment during which 8 deficiencies were cited, it is determined that the root cause of 6 of the 8 deficiencies pertains to employee training. In this example, additional investigation into the employee training program would be prudent and should be evident in the response supplied to A2LA.

The investigation which begins by asking “why did this deficiency occur?” will uncover a reason why the deficiency occurred. A proper root cause investigation will continue to ask ‘why did this occur’ until you can no longer identify a reason. At this point you can be reasonably assured that you have isolated the crux of the issue.

Additional resources that may be of help are found at:

"Presentation on Root Cause Analysis", found under "A2LA Guidance Documents" in the Document Finder on the A2LA website.

The February 2007 Issue of the A2LA Newsletter, found under the "Publications" tab, and "Newsletter Archive" menu item on the A2LA website.