ISO 9001: 2015 Clause 8.3.4 and Product Design

PLCs, programmable logic controllers


My company is implementing ISO 9001:2015 and my question is regarding Clause 8.3.4 d. Our company designs product for only 20% of our customer base. We do not have a validation process. We do send a prototype to the customer to test the part for a period of time to approve the design. In determining the scope of our organization, can we exclude the validation process and still become ISO 9001:2015 certified?


From John Surak:

This organization is involved in product design.  Therefore, the product design cannot be excluded.  However, the organization needs to review the validation clause.  8.3.4d states the following:   “validation activities are conducted to ensure that the resulting products and services meet the requirements for the specified application or intended use.”  It should be noted that neither 8.4.3d not the validation refences in ISO 9001 do not prescribe a method on how to conduct validation.  It would appear that the company has some sort of process they use to develop the prototypes.  This process should be codified or documented so that it is done in a consistent manner and in a way to ensure that the customer needs are met.

John G. Surak, PhD

From George Hummel:

Basically, you are outsourcing validation.  Therefore, you need to control that process per 8.4. I would not accept the exclusion. In the future, you may have a customer that requires you to do the validation. However, the final answer would be provided by your certification body.

Click here for more resources about ISO 9001: 2015.

ISO 17025 Clause 5.4.2 – Selection of Methods

ISO/IEC 17025:2017 General requirements for the competence of testing and calibration laboratoriesQ: We are working with the Mexican Accreditation Entity (EMA) for certification to ISO/IEC 17025:2005 General requirements for the competence of testing and calibration laboratories. Clause 5.4.2 states: The laboratory shall confirm that it can properly operate standard methods before introducing the tests or calibrations.

We are a testing laboratory and work with Method 21 – Determination of Volatile Organic Compound, EPA 40 CFR Ch.1 ( 01/07/04 Edition ) Test: Monitoring of Fugitive Emissions.

The question is: What would be the best way or a way to confirm the method? Or, to put it another way, how can we satisfy the requirements in clause 5.4.2 ?

A: The questioner is referring to clause 5.4.2 from ISO/IEC 17025:2005. An excerpt of this clause is below. Please refer to ISO/IEC 17025:2005 for the full clause.

5.4.2 Selection of methods

“…Methods published in international, regional or national standards shall preferably be used….. Laboratory-developed methods or methods adopted by the laboratory may also be used if they are appropriate for the intended use and if they are validated…. The customer shall be informed as to the method chosen. The laboratory shall confirm that it can properly operate standard methods before introducing the tests or calibrations.…”

Since the questioner is using the published methods, there is no need for validation of the method unless the method is modified.

However, the proficiency of being able to apply the published method needs to be demonstrated. This can be demonstrated by a documented Gage R & R study, Analysis of Variance (ANOVA) or Design of Experiments (DOE) study as appropriate to show proficiency in being able to utilize the test method properly.

The results from these studies may also be used to estimate the uncertainty of measurement for the tests. Reporting uncertainty of measurement with both test and calibration results is a requirement in ISO/IEC 17025:2005. The ILAC P14 document is a good guidance document on reporting uncertainty.

Dilip A Shah
President, E = mc3 Solutions
Chair, ASQ Measurement Quality Division (2012-2013)
Secretary and Member of the A2LA Board of Directors (2006-2014)
Medina, Ohio

For more on this topic, please visit ASQ’s website.

Operational Qualification (OQ) Challenges; Cpk vs. AQL

Q: We’re completing a validation of a plastic extrusion process, which has raised a few questions with me.

This validation exercise encompasses the installation qualification (IQ), operational qualification (OQ), and the performance qualification (PQ). The IQ is self explanatory, but the OQ is challenging. The process is dependent on the batch resin properties which vary enough that the extrusion processing parameters cannot be setup where good parts are always produced. One resin batch can use processing parameters that will not work with the next batch. A justification will be written and included in the documentation package to explain this. Does the inability of defining an operating window void or limit the validation?

My second question has to do with PQ acceptance criteria. The PQ will be three production runs using at least two different material resins (the largest source of variation). While production acceptance will be on an AQL=1.0, C=0 basis, these initial validation lots will be accepted on a process capability index (Cpk) level. While on the surface the acceptance difference may seem benign, it is causing some changes. The tolerance is such that the process routinely passes the Acceptable Quality Limit (AQL) test criteria but fails a Cpk requirement. Is it possible to accept PQ runs as they would be accepted in production?

A related question is the power of a Cpk vs. an AQL sampling plan. A Cpk value can be calculated using the same number of samples on a 100-foot run vs. a 10,000-foot run, while an AQL sampling plan is size dependant. Is there a criterion on sample size or a rule of thumb as to when one plan should be used over another?

A: First, the plastic extrusion process is always a tricky one to qualify simply because each new batch of resin always requires adjustments no matter how controlled the storage conditions are. So yes, you will have to define what adjustments your organization has to make and how big an operating window you need to transition from batch to batch.  If you can demonstrate that it can be resolved within a certain time (say, 15-30 minutes), then it should be ok for validation.  This is assuming that the customer is in agreement with what your company is doing.

Cpk formula, Cpk indexThe second question is a bit more difficult in that the Cpk is assuming that the process is in control and performing at a steady rate.  Cpk is a long term measure and requires the use of control charts to really control the process.  You may be able to work with your customer on help to get validated to the Cpk requirement, but you have to show the plan to get here.  In the past, some customers have been willing to provide an extended period to attain validation. You may want to talk to your customer representative to find out what help they can provide.

The third question gets to the fundamental heart of the situation: the question of using Cpk vs. AQL.  Cpk is a measure of process capability and AQL is a measure of long-term, outgoing quality.  Are they the same?  On some studies I did early on with Cpk and specifications, it was not always clear.  I have not seen any criterion on sample size on when to use Cpk vs. AQL.

Jim Bossert
SVP Process Design Manger, Process Optimization
Bank of America
Fort Worth, TX

For more on this topic, please visit ASQ’s website.