Rapid Screening for Lead Concentration Compliance by X-Ray Fluorescence (XRF) Analysis

摘要

A method is provided for screening lead concentration compliance of objects, particularly consumer products such as toys, using x-ray fluorescence (XRF) analysis. The measured intensity ratio of the characteristic L_α and L_β x-rays of lead provides an indication of whether the lead is located primarily in a coating (e.g., paint) layer on the object, or in a thin or thick bulk material. If the intensity ratio indicates that the lead is located in a coating layer or distributed in a thin bulk material, an areal density of lead is determined from at least one of the characteristic x-ray intensities, and the measured areal density is compared to specified lower and upper limits to determine whether the object is unambiguously compliant, unambiguously non-compliant, or indeterminate.