Certain brass alloys, namely those containing more than 15 weight percent zinc, are inherently susceptible to SCC even in water service. Therefore, choice of alloy is an important factor in preventing SCC. There are many brass alloys available which are resistant to SCC. In theory, if a brass alloy with resistance to SCC is chosen, then failure due to SCC should not occur. Typical failures of brass alloys due to SCC include cracking of brass plumbing fixtures, such as in residential bathroom lavatory faucets and commercial fire protection sprinkler systems, to name only a few. Other alloys like stainless steel are also susceptible to SCC in certain corrosive environments, namely, those containing chlorides. Chlorides are found in many cleaners, such as bleach. Some common failures of stainless steel due to SCC are braided flexible water supply lines to the toilet or lavatory. Needless to say, these failures often cause extensive water damage.
Many failures of threaded brass fittings are wrongly attributed to over tightening by the installer.
Stephen Cole's suggestions:
1. is the crack brittle in appearance?
2. Is the crack surface discolored due exposure to the environment?
If the answer to either of these questions is yes, then the cause for the failure is likely SCC. On smaller cases, document the evidence and send to the manufacturer and if it agrees its product failed, it will pay you. Otherwise, I suggest you engage an expert to examine the evidence and prepare for litigation.
Discussion courtesy of Lisa K. Thomas, P.E.,
Berkeley Engineering and Research, Inc