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Not in facts.json. Verbatim, 10.07(1)(a)1.c: "The joints shall be fluxed properly and fastened using lead free solder." 1.e: "Solder filler metals used in the fabrication of solder joints in potable water applications shall be lead free." 3.d: threaded potable joints "shall be made with lead free polytetrafluoroethylene sealant". 4: "Brazing filler metal and brazing fluxes ... shall be lead free."
Lead dissolves into water, especially water that is corrosive or sits in the pipe, and CDC says no safe blood lead level in children has been identified. Even low levels are tied to developmental delays and learning problems that can be permanent.
Solder joints, brass fittings and old lead lines are all places where lead touches water. The law shut off the new sources: first solder in 1986, then brass in 2011, when 8% lead was replaced by 0.25% averaged over wetted surfaces.
Flint showed the other half of the problem. When treatment stopped controlling corrosion, lead already in the system came out into the tap water.
The trade is named after the metal.
Source: https://www.etymonline.com/word/plumber
Safe Drinking Water Act Amendments of 1986 (Pub. L. 99-339, June 19, 1986) create the first federal lead-free definition.
Source: https://www.govinfo.gov/content/pkg/STATUTE-100/pdf/STATUTE-100-Pg642.pdf
Reduction of Lead in Drinking Water Act (Pub. L. 111-380, approved Jan. 4, 2011).
Source: https://www.govinfo.gov/content/pkg/PLAW-111publ380/pdf/PLAW-111publ380.pdf
The new definition takes effect 36 months after enactment (January 2014).
Source: https://www.govinfo.gov/content/pkg/PLAW-111publ380/pdf/PLAW-111publ380.pdf
Flint, Michigan: water source switched without corrosion control, and lead in tap water rises.
Source: https://www.cdc.gov/mmwr/volumes/65/wr/mm6525e1.htm
EPA final rule implementing the 2011 definition.
Source: https://www.epa.gov/sdwa/use-lead-free-pipes-fittings-fixtures-solder-and-flux-drinking-water
Mnemonic: 'Point-two for solder, point-two-five for brass.' 0.2% lead in solder and flux; 0.25% weighted average for wetted surfaces. And a true fact to remember it by: 'plumber' comes from plumbum, Latin for lead. The trade was named after the material it now has to keep out.
'Lead free' means zero lead.
It is a legal definition: 0.2% for solder and flux and 0.25% weighted average for wetted surfaces.
Exempt items mean lead is fine anywhere in a bathroom.
The exemption list is specific (for example tub fillers and shower valves). Lavatory and kitchen faucets are not on it.
Flint was caused by plumbers using lead solder.
CDC's MMWR attributes the rise in tap-water lead to the source switch without corrosion control. It was a treatment failure acting on existing plumbing.
What type of solder is required for potable water supply joints?
Lead leaches from solder into water that stands in the pipes, and it is a neurotoxin that is especially harmful to children. The Safe Drinking Water Act and 248 CMR limit solder and flux on potable lines to 0.2% lead, which bans 50/50 on water supply. Brazing is allowed but is not required on every joint.
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