The X-550 Pb utilizes miniaturized, rugged Rh tube (40 kV, 100 uA, 4 W) and Silicon Drift Detector for measurement of lead-based paint in units of mg/cm2. The X-550 Pb is world’s only handheld XRF accepted by HUD and EPA for testing residential, day care, schools and other such properties via a published Performance Characteristics Sheet (PCS). It provides analysis of lead (Pb) loadings both for surface and deeply covered lead in paint in as little as 1 second, as well as a risk-assessment indicator if the lead is on the surface or covered by non-lead containing paint.