Design Defect
Definition
A flaw present in every unit of a product because the product category itself was conceived in a way that made it unreasonably dangerous, not because any individual unit was made incorrectly.
- Field
- Product liability engineering
- Scope
- Affects every unit of the product line
- Contrast
- Distinct from a manufacturing defect in a single unit
- Common test
- Risk-utility balancing or safer-alternative-design comparison
Common questions
How is a design defect proven in an investigation?+
An engineer typically compares the product's risk profile against a feasible alternative design that would have prevented or reduced the injury at similar cost and function, since showing the category itself was unreasonably dangerous requires more than pointing to the one unit that failed.
Why does the design-versus-manufacturing distinction matter for liability?+
A manufacturing defect implicates one production run or batch, while a design defect implicates the entire product line, which changes the scope of recall, the pool of claimants, and the kind of evidence, such as design files and alternative-design testing, that an investigation needs to gather.
Related terms
- Consumer Expectation Test
- A design-defect test asking whether the product failed to perform as safely as an ordinary consumer would expect when used in an...
- Failure to Warn
- A claim that the manufacturer failed to provide adequate instructions or warnings about a non-obvious risk, such that a user could not...
- Foreseeable Misuse
- A use of a product that the manufacturer could reasonably predict, even though it differs from the intended purpose. Courts may hold...
- Manufacturing Defect
- A deviation in a specific production unit from the manufacturer's approved design specification, occurring during manufacturing, assembly, or handling before sale. The...
- Risk-Utility Test
- A design-defect test that weighs the probability and severity of harm, the burden of adopting a safer alternative design, and the utility...