product development articles

Design Controls: Just Good Design Practices


In the world of medical device product development, we often hear complaints about the burden of design controls.  However, when you examine the elements of design controls, you see they actually represent good design and engineering practices.  The goal of these practices is to show that you can manufacture products of the required quality as expected.[1]  To show that you followed the practices, the regulatory bodies require that you document your work.  Below is a list of each design control requirement along with a description of how the engineering practice applies.

  • Planning: When starting a project, you spend time defining how the project will proceed. There are a number of elements for the project to be considered including: 1) define the planned outcome or object to be delivered, 2) the scope of the project, 3) how the work will be organized, 4) who will do what and when, 5) identification of important risks to be addressed, and 6) concept/product testing.  As you proceed with the project, the plan is updated based on newer information.  (Many of these elements are also consistent with the planning requirements identified in the Project Management Institute PMBOK[2] )
  • Design Inputs: As an engineer, the product requirements drive the product design. While the requirements don’t define the product solution, they do cover the final design performance.  These requirements also need to include elements which are often assumed, such as capable of using the power outlets in the country of sale.  Designing a new product without a solid understanding of the necessary, final requirements often leads to the wrong product, redesign, and wasted time and effort.
  • Design Outputs: Once the product is designed, you need to document the design to ensure it can be properly manufactured. Drawings, formulations, and test methods are often used to instruct manufacturing how to make and test the product.
  • Design Review: During development, periodically checking the design against the requirements helps to ensure that the final product will work as intended. There are several types of reviews you can hold including: 1) technical which is focused on the detailed design and 2) project level to review feedback from other project stakeholders.  IEC 61160 Design Review provides excellent information on different types of design reviews and typical reviewers.
  • Design Verification: Once the design is complete, you check to see that it performs correctly against the product requirements. This is usually done by testing components, sub-assemblies, and the fully assembled product.
  • Design Validation: Another important aspect of product development is ensuring that the product addresses the user needs. Testing the final product with the user, under conditions in which they are likely to use the product, enables you to determine if the product works as intended.
  • Design Transfer: It is important to work with manufacturing to ensure they can reliably and reproducibly make the product. Once transferred, operations should have the knowledge to troubleshoot any problems and the capability to maintain the product.
  • Design Changes: Once the product design has been set, such as through a design freeze, any changes to the design need to be evaluated for impact to the product performance against the requirements, then documented.
  • Design History File: Documenting the product design, decisions, and what you learned along the way, including what worked and what didn’t, are an important source of information that can be used to support the product for its lifetime. The product history may also be used as the starting point for future product versions or enhancements.

As you can see, design controls are really just good design practices.  When you look at the requirements, you can choose to approach them as a documentation burden or you can use them to help make the right product for your customer and for your organization.


[1] Good engineering practice. (2015, January 8). In Wikipedia, The Free Encyclopedia. Retrieved 17:06, December 2, 2015, from

[2] Project Management Institute. (2013).A guide to the project management body of knowledge (PMBOK guide) – Fifth edition. Newtown Square, Pa: Project Management Institute.