Product defects come in three flavors: manufacturing, design, and warning. Each type affects products differently and can lead to injuries. Understanding these defects is crucial for determining liability in product-related accidents.

Manufacturers must ensure their products are reasonably safe. This means balancing utility against risks. Courts use various tests to evaluate defects, considering factors like consumer expectations and the adequacy of warnings. These assessments help determine if a product is legally defective.

Types of Product Defects

Types of product defects

• Manufacturing defects happen when a product strays from its intended design, even though all possible care was taken in the preparation and marketing of the product (defective car tire, contaminated medication)
  • Usually affect a small percentage of products in a product line
  • Strict liability applies regardless of the level of care exercised by the manufacturer
• Design defects exist when the foreseeable risks of harm posed by the product could have been reduced or avoided by adopting a reasonable alternative design (lack of safety features on power tools, unstable furniture prone to tipping over)
  • Affect an entire product line since the defect is inherent in the design
  • Negligence or strict liability may apply depending on the jurisdiction
• Warning defects, also known as marketing defects, occur when a product has inadequate instructions or warnings regarding foreseeable risks of harm (lack of allergen information on food labels, missing safety warnings on cleaning products)
  • Can exist even if the product is properly manufactured and designed
  • Negligence or strict liability may apply depending on the jurisdiction

Concept of reasonably safe products

• A product is considered reasonably safe if its utility outweighs its risks (benefits of a life-saving drug vs. its potential side effects)
• For manufacturing defects, a product with a manufacturing defect is not reasonably safe because it deviates from the intended design (a bicycle with a cracked frame due to a manufacturing error)
• For design defects, a product is not reasonably safe if there exists a reasonable alternative design that would have reduced or avoided foreseeable risks of harm (a safer blade guard design for a table saw)
• For warning defects, a product is not reasonably safe if it lacks adequate instructions or warnings regarding foreseeable risks of harm (insufficient warnings about the risk of electric shock on a hair dryer)

Evaluating Product Defects

Factors in defect determination

• Design defects are evaluated using:
  1. Risk-utility balancing test weighs the utility of the product against the risks it poses, considering factors such as the magnitude and probability of foreseeable risks of harm, instructions and warnings accompanying the product, and the nature and strength of consumer expectations (a car's fuel tank design that increases the risk of fire in rear-end collisions)
  2. Consumer expectations test deems a product defective if it fails to perform as safely as an ordinary consumer would expect when used in an intended or reasonably foreseeable manner (a ladder that collapses under normal use)
• Warning defects are assessed based on:
  • Adequacy of warnings and instructions, which must be clear, conspicuous, and understandable to the average user, covering all foreseeable risks associated with the product (insufficient warnings about the risk of explosion when using a propane grill)
  • Causation, where the plaintiff must prove that the inadequate warning or instruction caused their injury (failure to warn about the risk of a drug's side effects leading to patient harm)

Tests for product defects

• Manufacturing defect scenario: A car's brakes fail due to a manufacturing error, causing an accident. Strict liability applies because the brakes deviated from their intended design.
• Design defect scenario: A lawnmower lacks a blade guard, resulting in injuries to users. The risk-utility balancing test would consider whether the utility of the lawnmower outweighs the risks posed by the lack of a blade guard and whether a reasonable alternative design, such as including a blade guard, would have reduced or avoided foreseeable risks of harm.
• Warning defect scenario: A cleaning product lacks adequate warnings about its toxicity, leading to injuries when users mix it with other chemicals. The adequacy of the warnings would be evaluated based on whether they clearly and conspicuously covered the foreseeable risks associated with the product, such as the dangers of mixing it with other chemicals.