The US federal Safe Drinking Water Act (SDWA) was amended in 2011 to reduce the acceptable level of lead (Pb) to 0.25% in pipes, plumbing fittings and fixtures, solder, and flux that come into contact with potable drinking water. Effective in January 2014, the amended provisions require all suppliers involved in manufacturing, material handling, and installing brass plumbing components to comply with the Safe Drinking Water Act. X-ray fluorescence (XRF) is used to determine highly specific material chemistry, allowing rapid and accurate identification of metal grades for compliance with the Safe Water Drinking Act. The Olympus Vanta™ XRF analyzer confirms alloy chemistry, including lead content and various other toxic elements, and provides a grade ID in seconds. The Vanta analyzer is used for simple sorting, incoming material inspection, and end-product verification. |
Using XRF for EPA Lead Requirements
According to the Safe Water Drinking Act, all pipes, fittings, and fixtures manufactured and used in the US to carry potable water must be “lead free.” Section 1417 of the Safe Drinking Water Act establishes the definition for lead free as a weighted average of 0.25% lead calculated across the wetted surfaces of a pipe, pipe fitting, plumbing fitting, and fixture and 0.2% lead for solder and flux. Under the methodology established by this law, XRF is well suited to calculate average lead contact along the surfaces of pipes and plumbing fittings/fixtures.
Ideally, each individual component should be tested for lead. Testing for the presence of lead prevents material mix-ups and determines the levels of lead present in components. Studies have shown that the presence of chlorine in tap water accelerates the leeching of lead from plumbing components. It has also been shown that diffusion of lead into drinking water is correlated with lead concentration in piping and plumbing components. The Vanta handheld XRF analyzer offers several advantages:
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Using the Vanta VCR model, we analyzed several brass and copper alloy certified reference materials (CRMs) for various heavy metals and regulated elements. The Vanta XRF analyzer’s excellent ability to detect low levels of lead in various EnviroBrasses for compliance with the 0.25% lead requirement is shown below. Quantification of lead was achieved at over 10 times below the action level. In addition, we analyzed an older, noncompliant brass sample for comparison.
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Additionally, the Vanta analyzer can effectively measure several other elements of concern for drinking water safety, including arsenic (As) and cadmium (Cd). Below are results from testing several brass CRMs for other toxic elements.
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Olympus Vanta handheld XRF analyzers perform reliable positive material identification (PMI) and QA/QC of brass plumbing components to help users comply with the Safe Drinking Water Act. Vanta analyzers provide highly specific material chemistry to rapidly and accurately identify alloy grades and verify compliance to compositional requirements in seconds. |