A specification that defines the function, performance, and interfaces of a product but does not specify explicit design and materials is called what?

• A. Functional specification
• B. Performance specification
• C. Design specification
• D. Interface specification

Answer: (B)

Performance specifications describe what the product must achieve in terms of results and how it will interact with other components, without prescribing how it should be built or what materials to use. They set measurable performance criteria, acceptable tolerances, and interface requirements, but leave design choices and materials up to the supplier. This allows multiple design approaches to meet the same outcomes, promoting flexibility and competition while ensuring the end behavior and compatibility are clear.

In the given scenario, the focus is on what the product must do (function and performance) and how it will connect with other parts (interfaces) while not dictating the construction details. That alignment is why this is a performance specification. A functional specification would emphasize the required functions and features, a design specification would specify materials and construction, and an interface specification would zero in on the exact interfaces alone.