Swab Lead Tests
Now that the public is becoming more informed about the lead laws and the intricacies surrounding them we are encountering more questions about swab lead tests. We will answer the three most common questions we’re being asked:
1. Why does Lead Safe Testing not endorse the use of swab lead tests?
Perhaps most importantly swab tests are very difficult to properly use. Under laboratory conditions your average scientist may be able to determine the concentration of lead in a given paint sample utilizing the swab test kits sold at hardware stores. By this we mean that a scientist would verify that they are testing EVERY LAYER OF PAINT that was lifted from a given component in a home. If you’re not testing EVERY LAYER OF PAINT on EVERY AFFECTED COMPONENT in your home you’re not performing a valid swab test thereby nullifying any results that you produce.
IT IS EXTREMELY DIFFICULT TO CUT AND LIFT A SAMPLE OF PAINT FROM A GIVEN COMPONENT THAT INCLUDES EVERY LAYER OF PAINT THAT HAS BEEN APPLIED TO THAT COMPONENT.
Secondarily, even if a person is able to properly cut and lift a paint sample that includes all of the layers of paint from a given component, the likelihood of them doing so without taking some substrate with the paint sample is virtually zero. Some substrate (drywall paper, drywall dust, wood debris, concrete particles, etc.) will come up with the bottom layer of paint to be tested. The addition of these substrate particles skews the results of the swab test because your parts-per-million concentration is incorrect and therefore not representative of the paint sample. If your parts-per-million concentration is inaccurate FALSE NEGATIVES OCCUR. A false negative is what CAN PUT YOUR FAMILY IN DANGER.
IT IS EXTREMELY DIFFICULT, IF NOT IMPOSSIBLE, TO OBTAIN A PAINT SAMPLE WITHOUT TAKING SOME OF THE SUBSTRATE PARTICLES WITH THE PAINT SAMPLE. THIS CAN RESULT IN INNACCURATE AND POTENTIALLY DANGEROUS “FALSE NEGATIVE” RESULTS.
2. Isn’t it less expensive to use swab tests instead of an XRF test?
This is not the case as long as the company utilizing the swab test is properly executing the test. Each swab test kit comes with six swabs which will properly test only six components/surfaces. The average remodel project, when properly tested, averages forty samples. Each swab test kit costs $30.00. If you are doing an average remodel you would be spending almost $200 just for the swabs. Add the time it takes to perform the testing and complete the reporting and you are usually better off having an XRF test performed. Keep in mind that SWAB TESTS ARE INVASIVE TESTS THAT CAUSE DAMAGE TO COMPONENTS OF YOUR HOME requiring additional costs for repairs. An XRF test causes no damage to any part of your home. It’s also much faster to utilize the XRF testing than the swab tests, so figure in your time savings and it only makes sense to utilize the XRF test.
3. We understand that a remodeling company must by law retain the results of a lead test for three years, how do you do that with swab tests?
This is certainly an issue when it comes to swab testing. At the end of a swab test you are left with a bag of pink-colored swabs and other test kit equipment that BY LAW, MUST BE RETAINED FOR THREE YEARS after the test’s completion in order to prove the results of the test. Saving all of those plastic bags full of lead swab tests from each of your remodel projects is certainly not appealing and may not even be possible for a contracting company. Lead Safe Testing produces an EPA certified report on paper which can be filed for decades. It takes up very little space and can even be sent and saved electronically, taking up no space. Again, the XRF test results are really the only way to go when thinking practically about the test retention laws.
THERE IS NO GOOD WAY TO STORE THE RESULTS OF A LEAD SWAB TEST FOR THREE YEARS AS REQUIRED BY LAW.
Hopefully this helps to answer some of the questions and clarify some of the misconceptions about swab-style lead tests. These are the three most common questions we’ve been hit with concerning swab tests. Feel free to submit your questions or concerns to [email protected]. Thank you!