Water Supply & Distribution第 49 / 120 题
What is the maximum lead content permitted in solder and flux used on a potable water piping system?
a.0.2 percent
b.0.25 percent
c.2 percent
d.8 percent
解析
Solder and flux used in potable water piping may not exceed 0.2 percent lead, which is why 50/50 tin-lead solder is prohibited. The 0.25 percent figure is a different limit, the weighted average lead content allowed on the wetted surfaces of pipe, fittings, and fixtures. The 2 percent and 8 percent values are far above any lead-free standard and describe legacy alloys no longer permitted.
法律依据: UPC §604.0免费刷完整 120 道题库 — 无需注册。
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