Developing Testable Requirements

I have previously written about the importance of having requirements in the blog ‘Requirements – do you have your shopping list ready’. Without a list of requirements, the consumer is likely to end up with some items/features they did not need, while missing some items/features they did need. Having a list is a good starting point, but having a testable set of requirements will lead you to success.

The biggest challenge may be determining items that are needs vs. wants. Users of a product or piece of equipment can usually put together a list of items they feel are important when purchasing a new product. Sometimes having an external view of that list helps confirm the items that are needs, versus those that are wants. Everybody has a budget, it is vital that money is being spent on needs first, if there are funds left over that’s when wants can be included.

The requirements need to be specific enough that the person completing the selection can evaluate products against those requirements. For example, let’s imagine you were asked to pick up ‘bread’ on your way home. You pick up a loaf of white French bread. When you get home, your spouse lets you know they wanted a loaf of sliced whole wheat bread. Simply saying you want bread is not sufficient.

Referencing a broad standard presents challenges for the shopper as well. If you were looking for a new chair your requirements could suggest that the chair shall meet CSAZ412 – Guideline on Office Ergonomics. That document is huge, what would be more helpful would be list out the items from section 7.4 which are relevant. For example:

  • The seat height shall adjust through a height range of 380-510 mm.
  • The seat depth shall be adjustable by a minimum of 50 mm.
  • Etc.

professional ergonomist can help you determine ergonomic requirements, differentiating wants from needs. They can also pull information from relevant standards to help create testable requirements. All of this works towards the goal of selecting a product with the features you need.