Product Liability Case Study: Failure of Brass Plumbing Fitting due to Stress Corrosion Cracking

Abstract This case study examines a product liability dispute involving stress corrosion cracking (SCC) failure of a brass plumbing fitting that caused significant water damage to a Minnesota home in 2018. The investigation identified SCC as the failure mechanism, with three contributing factors: a high-zinc brass alloy (UNS C27451 with 38.3 wt% zinc) susceptible to cracking, exposure to potable water service conditions, and sustained tensile stresses from installation, manufacturing residual stress, and system pressure. The dispute involved the homeowner, fitting manufacturer, general contractor, and plumbing installer, with conflicting expert opinions regarding whether improper installation or product defect was primarily responsible. The case highlights the importance of materials selection, manufacturing processes, and the challenges of assessing installation practices after failure in determining liability for SCC failures in brass plumbing components.