Testing* for Lead in Solder
click here for a printable version

Background: Lead solders were banned from use on plumbing lines that bring water to a tap in 1986. While the law prohibits use of solder in excess of 0.2% lead in plumbing applications, the fact is that the plumbing found in many households still contains lead/tin solder with a lead content of 37% or higher. LeadCheck® Swabs can be used to screen for lead solders used in household plumbing. LeadCheck® Swabs will always turn pink when the lead concentration is greater than 0.2% City and State building code inspectors in several states, including Texas and Ohio, use LeadCheck® Swabs in the field to determine if the solder used conforms to Federal Codes. LeadCheck® Swabs for solder may detect lead is as low as 0.1%. At greater than 0.1%, a LeadCheck® Swab turns pink or red when testing commonly used tin/lead solders. LeadCheck® Swabs will not turn pink when testing lower than 0.1%. Test Method: Wipe dirt off the solder joint of your pipe with a paper towel or cloth. Rough up the surface of the solder joint with an emery cloth or sandpaper and wipe clean. Activate a LeadCheck® Swab according to the directions. Squeeze and maintain pressure on the Swab barrel to keep a drop of the (yellow/orange) LeadCheck® reagent at the swab tip. Touch the drop of LeadCheck® reagent to the prepared solder surface and lightly brush the surface with the Swab tip, DO NOT RUB.1 Interpretation: If the tip of the swab turns pink or red, the solder contains greater than 0.2% lead. If the tip of the Swab turns purple, high levels of tin have been detected. Repeat the test making sure to just touch and dab the drop of LeadCheckk® reagent on the solder surface - Do Not Rub! The rate of reaction with lead is immediate – the LeadCheckk® reagent turns pink. The rate of reaction with tin is delayed and causes the LeadCheck® reagent to turn purple. Testing Solder Samples (Expected Results) Solder from a roll is pounded flat with a hammer. The flattened sample is tested according to instructions. Solder from a roll is pounded flat with a hammer. Swab on left is a direct test without cleaning. Swab on right is a direct test after wiping solder with alcohol wipe. Test solder joint on a copper pipe after wiping the surface with an alcohol wipe. Note: 1Vigorous rubbing may cause a metallic film to be deposited on the Swab tip. By lighlty rubbing or dabbing the LeadCheck® reagent on the prepared solder surface the Swab tip will turn pink first, followed by a purple color if tin is present. *LeadCheck® Swabs are a versatile and sensitive screening tool for the detection of lead on any surface. This applications note provides a suggested method to allow testing for a specific application. Additional information and help are available by calling 800-262-5323 or 508-651-7881.