Water Supply & DistributionQuestion 47 of 360
Why must dissimilar metals, such as copper tube connecting to galvanized steel pipe, be joined with a dielectric fitting?
a.To increase flow
b.To reduce noise
c.To prevent galvanic (electrolytic) corrosion at the joint between dissimilar metals
d.To allow threading
Explanation
Joining dissimilar metals directly promotes galvanic corrosion, so a dielectric fitting is used to electrically separate them and prevent that corrosion. Dielectric fittings are not installed to increase flow, reduce noise, or allow threading.
Law Reference: 2022 California Plumbing Code (CPC) §605.0Practice all 360 questions free — no signup required.
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