For many centuries, lead was the favoured material for water pipes, because its malleability made it practical to work into the desired shape. (Such use was so common that the word "plumbing" derives from plumbum, the Latin word for lead.) This was a source of lead-related health problems in the years before the health hazards of ingesting lead were fully understood; among these were stillbirths and high rates of infant mortality. Lead water pipes were still widely used in the early 20th century, and remain in many households. In addition, lead-tin alloy solder was commonly used to join copper pipes, but modern practice uses tin-antimony alloy solder instead, in order to eliminate lead hazards.[13]

If you decide to try this job yourself, be prepared to keep meticulous track of about a dozen tiny parts (put the stopper in the sink so none of them fall down the drain). There are many different faucet designs, so you may not be able to tell what to replace until you've done the disassembly. Whether you do it yourself or hire a plumber, this would be a good time to think about whether you want to upgrade the faucet with a new design.
Journeyman plumber: Once the requirements of an apprenticeship are fulfilled, plumbers can apply for a journeyman license. Many workers in the plumbing industry are journeymen. Obtaining a journeyman's license requires a fee and the successful passing of an exam. Licenses vary by state, although not all areas require journeymen to be licensed. Instead, the amount of work they are able to perform is limited.
Although plumbers, pipefitters, and steamfitters perform three distinct and specialized roles, their duties are often similar. For example, they all install pipes and fittings that carry water, steam, air, or other liquids or gases. They determine the necessary materials for a job, connect pipes, and perform pressure tests to ensure that a pipe system is airtight and watertight. Their tools include drills, saws, welding torches, and wrenches.
A leaky faucet can be a relatively easy fix depending on the type of faucet, so get to know the basic types of faucets and how to take them apart. You can look for instructions online; YouTube videos are the most useful. A slow drip usually means that all you have to replace is a washer, but make sure you know which size you need before buying a new one.

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