Hello, good people of the world! Recovery studies are studies to support surface swab processes. They typically involve “spiking” a “coupon” made from a particular material with a known amount of the contaminate you’re interested in, and then systematically quantifying the amount recovered via the swab process.
You’ll need to perform recovery studies for all product-contact materials you have in your manufacturing process. These typically include 316L stainless steel, PTFE, glass, etc.