Lead-tin solder ban and plumbing failures (1978)
Appears in 1 lecture.
Appearances across the corpus
Brief mention — Massachusetts outlawed lead-tin solders in 1978. Used as evidence of the regulatory shift away from lead in plumbing.
It turns out when you machine a leaded brass, the lead doesn't mix with the copper and zinc. It forms little islands, inclusions of lead. When you machine it, the lead heats up, melts, and forms a lubricant. You can machine leaded brass about five times faster than regular brass. So it's cost again. We used to use leaded brass, and we never thought the amount of lead leaching out of the water was turning all the children ignorant. Well, in fact it wasn't — it was genetics that made them ignorant. But mom and dad don't want to think the genetics made their children ignorant; they want all the lead out of the system. In 1978 Massachusetts outlawed lead-tin solders, and now they only have tin solders for making plumbing.