Water Supply & Distribution第 50 / 120 题
What is the maximum weighted average lead content permitted on the wetted surfaces of pipe, fittings, and fixtures used to convey water for human consumption?
a.0.2 percent
b.0.05 percent
c.0.25 percent
d.8 percent
解析
The lead-free standard limits the wetted surfaces to a weighted average of not more than 0.25 percent lead. The 0.2 percent value is the separate limit that applies to solder and flux, not to the wetted surfaces of the components. The 0.05 percent figure is stricter than the code requires, and 8 percent describes older leaded brass that may no longer be installed in potable systems.
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