Is There Asbestos In Plaster?
Love Angel got it right. Old plaster can contain asbestos – it increased the strength and workability of the plaster. It really took off as a “wonder material” during the 1920’s and through WWII. So the house age is definite risk. I find it even in drywall joint compound used the 1960s and 1970s, (but in that use, it typically composites to less than 1% when you factor in the drywall sheets themselves). In small quantities, a lab test (using a polarized light microscope) is $30. You want to send them the full thickness of any material so they can look at the individual layers. I’ve most recently been using NVL in Seattle 206-547-0100. For drywall/sheetrock, you should sample at the taped joints because that is the worst case. In two-coat plaster, sample whereever is it easy, convenient and safe (below your breathing zone is better than above). Mist the area down with a soapy water solution when collecting the sample (to minimize dust). DON’T dry sand or dry sawcut it. Ideally, break of
