The unit mg/cm2 is used to report lead quantity for which testing method?

The unit mg/cm2 is used to report lead quantity for which testing method?

• A. Paint Chip
• B. ICP-MS
• C. AAS
• D. XRF

Answer: (D)

mg/cm2 is a surface-area density—it's a way to express how much lead is present on each square centimeter of a painted surface. XRF is designed to assess surfaces directly and reports results in this area-based unit, giving a quick measure of lead per area on the coating without removing it. In contrast, the paint chip method yields results like lead per chip or per weight of paint, and ICP-MS or AAS require digesting a sample and report concentrations such as mg/kg or mg/L, not per unit area. So mg/cm2 matches how XRF reports lead when screening surfaces.

mg/cm2 is a surface-area density—it's a way to express how much lead is present on each square centimeter of a painted surface. XRF is designed to assess surfaces directly and reports results in this area-based unit, giving a quick measure of lead per area on the coating without removing it. In contrast, the paint chip method yields results like lead per chip or per weight of paint, and ICP-MS or AAS require digesting a sample and report concentrations such as mg/kg or mg/L, not per unit area. So mg/cm2 matches how XRF reports lead when screening surfaces.