SBIR-STTR Award

Lead is a highly toxic substance, causing serious health problems, particularly in children. The EPA and HUD consider lead paint to be a primary source of lead poisoning. Commercial paint no longer contains lead and government agencies have called for its removal from older homes. One significant problem is the lack of rapid, inexpensive, reliable methods for measuring levels of lead in concentrations as low as 1 mg/cm2. NITON Corporation proposes an inexpensive portable x-ray fluorescence (XRF) detector of lead paint based on measuring the L x-ray lines of lead rather than the K x-ray lines. Contrary to common wisdom and literature, they feel that this properly designed detector could measure concentrations of lead below 1 mg/cm2, under many layers of lead-free paint. The L x-ray detector is very sensitive to so-called matrix effects, but analysis indicates that these could be successfully dealt with if account is taken of the full XRF energy spectrum of good energy resolution. In Phase I, they would develop the first stage of the detector and study the matrix effects. In Phase II, they plan to construct a prototype XRF detector and test it.

Lead paint is a primary source of lead poisoning, particularly in children. A central problem to a more vigorous attack on finding lead-paint surfaces is the lack of an inexpensive, portable method for measuring levels of lead in concentrations as least as low as 1 mg per cm2. In Phase I, Niton Corporation proposed to show the L x-ray lines of lead rather than K x-rays could be used to measure lead concentrations buried beneath many layers of non-lead paint. They further proposed to develop a portable, high-resolution detector of L x-rays of lead. They have surpassed all of the goals of Phase I. They have proved that L x-ray fluorescence can quickly measure lead concentrations to well below 1 mg/cm2, even when the lead is covered by many layers of paint of unknown thickness and composition. Niton Corporation has built a laboratory prototype of a small, portable unit, with excellent energy resolution and spectrum analysis, that demonstrates the effectiveness of the method. The response from lead inspection professionals has been very positive. It is the primary purpose of Phase II to develop the technique further with the specific aims of dramatically reducing the costs of the instrument. The commercial potential for such an instrument is extremely high.