Mark Hammar In the minds of many people, there can be confusion between the meanings of “design verification” and “design validation” within the Quality Management System (QMS), and sometimes people will use these terms interchangeably. However, these two terms have distinct meanings within the design process defined in the AS9100 Rev D requirements. To better understand how these terms fit into the design and development process, it is best to quickly go over how the design and development process in AS9100 Rev D is specified.
How does the design process work in AS9100 Rev D?
The design & development process in AS9100 Rev D is a five-step process that is designed to allow you the freedom to align how you design your products and services to the needs you have for your specific situation. The five steps are as follows:
- Plan your design and development – This allows you to make a plan of what you will do for each design. This is important because the requirements of each design will be different, especially between your products and your services.
- Define your inputs – What are the requirements you need to meet with this design? Think of all requirements from customers, internal needs, legal requirements, industry standards, etc.
- Define your controls – What controls will be needed in this design? What reviews, verifications, and validation activities do you need to do to ensure that you achieve the necessary results?
- Create your outputs – What is needed for this product or service design so that you can create and deliver it? This can include drawings, test plans, specifications, and many more design items.
- Control changes – On an ongoing basis, you need to have a process in place to ensure that your design outputs are kept up to date when a change is identified, such as through continual improvement activities in your QMS.
As you can see, the design verification and design validation activities are part of the design controls you put in place during your design and development plan. Here’s more on the differences between these two design controls:
What is design verification?
Design verification is identified in the AS9100 Rev D standard as the process that is necessary to ensure the design outputs meet the design input requirements. So, this is a mostly a paper exercise that is done before you even create the product or service you are designing. When the design outputs are created, you need to compare this documented information against the design requirements to ensure that everything is covered. For instance, if your product or service needs five tests performed, does your test plan include these five tests in the criteria specified in the design requirements?
What is design validation?
In AS9100 Rev D, design validation is necessary to ensure that the products and services that result from your design and development activities meet the design requirements of the specified application or intended use. This is where you actually create the product or service and make sure that the result actually does what you designed it to do; in other words, you ensure that the design meets the requirements that it needs to meet. Some companies will do prototypes for this, while others will perform testing on subcomponents (such as smaller pieces of code) before the total product or service is completed. In all cases, you will actually need a sample of the product or service to validate it.
One thing to keep in mind, which also confuses some people, is that the term “validation” is used elsewhere in the AS9100 Rev D standard with respect to validating processes. This is completely separate from the design and development activities, and is done by using your process to ensure that said process will create the products and services you need it to create. For a better understanding of process validation, see this 9001Academy article on How to establish process validation in the QMS.
Is there a change in the new AS9100 Rev D?
The new revision of AS9100 has not changed the meanings of design verification and design validation, but instead has merged the requirements of these two design activities under one heading. In the previous version of AS9100, there was a separate sub-clause on design verification, and another sub-clause on design validation: however, in AS9100 Rev D these two activities have been put together under the heading of design and development controls. Even with these changes, these two activities are still equally important in your design and development process.
Why understanding the difference between design verification and design validation matters
Part of the problem with misunderstanding what is expected of design verification and design validation is that people will start to think that one or the other is not required within their company’s design process. It is important to ensure that the design outputs include everything that is needed, and to ensure that your resulting product or service meets the requirements for the intended use.
By skipping design verification, you may forget to include a check that is required during the validation of your product or service, which would ultimately have ensured that the product or service does what is needed. These two activities go hand-in-hand, but they are not the same thing. For a better design and development activity, make sure you understand how these two activities work together within your design and development process.
For a better understanding of the AS9100 Rev D requirements for design verification and design validation, see this free white paper: Clause-by-clause explanation of AS9100 Rev D.
