Are all Chinese Drywall inspections the same? No. XRF testing is a superior protocol because it basically brings a portable laboratory to your home. A common feature found in most cases of reactive drywall is a significantly higher level of the element Strontium and can be an indicator for Chinese drywall as outlined in test reports commissioned by the CSPC. Recently, there have been instances where false positives and negatives have occurred. These instances are not common, but for now the CPSC no longer recognizes the element Sr in levels above 1,200 ppm as a marker. Nonetheless, XRF testing remains a very powerful tool in the search for defective drywall. Visual inspections can be unreliable. The risk of a misdiagnosis is high and the consequences costly. In many cases the classic sign