Lead Paint Inspections: X-Ray Fluorescence (XRF) or Paint Chip
What is a Lead Paint Inspection with XRF?
Portable XRF lead-based paint analyzers are the most common primary analytical method for inspections to determine if lead-based paint is present on many surfaces and to measure the paint without destructive sampling or paint removal.
This method of inspection utilizes an XRF handheld device which can evaluate painted surfaces and provide results within seconds. This device works by bombarding the area with gamma rays or high energy x-rays which interact with the paint. Once the radiation interacts with lead atoms, they knock off the outer electrons of the atom’s orbit. Once the electron is dislodged, another electron will come to fill its place which in turn emits an x-ray. The x-ray’s energy signature is then detected by the XRF handheld device which is programmed to detect only lead’s x-ray energy peaks. Once the data is analyzed, the XRF device will display a lead reading. This method’s quick turn-around-time allows it to be able to inspect an entire home for lead without the need to submit samples to a laboratory.
What is Paint Chip Sampling For Lead?
Paint chip testing refers to the destructive method of lead sampling. This method involves collecting all the paint layers of a surface while leaving the substrate behind. It is imperative to collect as little of the substrate as possible as it may bias the laboratory result. The process is usually conducted using a utility knife or chisel sometimes in tandem with a heat gun to remove an area of paint usually no more than 4 square inches. After sampling is completed, the inspector will clean up any residual debris. It is recommended that the homeowner repair the sampled area after collection to stabilize the now damaged paint. The sample is then submitted to an accredited laboratory for analysis via the Flame Atomic Absorption Spectrometry method (Flame AAS). During this process, the sample is dissolved in nitric acid which is called the digestion process. The sample solution is then fed through a Flame AAS instrument which can accurately detect lead concentration based on the analysis of the light spectra of the flame.
If you are concerned with lead paint in your property please contact us.