AWWA JAW6663 ✓ Most Recent

Lead-based solders have been used for many years in both residential and commercial water distribution lines. When these solders come into contact with corrosive waters, lead may be leached out in concentrations which exceed the U.S. Environmental Protection Agency's primary drinking water standard of 0.05 mg/L. The problems of lead corrosion have prompted municipal and private water distributors to consider replacing the lead-based solders with tin-antimony solders. The Seattle Water Department in Washington is one such distributor. The primary source of water for Seattle is of high quality but corrosive. Presented is a theoretical analysis of antimony corrosion, tin corrosion, and galvanic coupling relationships. Results of coupon and field tests conducted to verify the theory are also included. The theoretical and experimental results obtained indicate that 95-5 tinantimony has a potential for replacing lead-based solders in plumbing systems. If tin-antimony solder is used in plumbing systems, the subsequent increase in the antimony concentration of the drinking water is minimal. Includes 12 references, tables, figures. See more