Solution Summary: Hand-held XRF Gun for Lead Testing
Hand-held X-Ray Fluorescence (hXRF) guns are portable analytical tools that can measure metal concentrations in a variety of materials. They are nondestructive, which means that users do not need to scrape or chip off samples for analysis. The hXRF gun emits an x-ray beam which hits the material of interest and sends information back to the gun. In a few seconds or minutes, a read-out will show the concentration of metals in the targeted material. hXRF guns are useful hazard identification tools for workers who are sanding, scraping, grinding, or performing abrasive blasting and suspect that lead paint may be present.
hXRF guns work by directing x-ray beams into the material of interest, which excites the electrons in different molecules and ejects them from their orbit. As other electrons fall in to replace them, they emit specific amounts of energy. Each element has a unique energy “signature” during this process. The hXRF gun measures the energy emitted and matches it with the correct element.
There are a large number of hXRF gun models available for a variety of uses, including occupational safety and health, food safety, metals processing, and waste management. The type of hXRF gun you should use depends on how you plan to use it and what you are looking for. The following models of hXRF guns are appropriate for lead identification in a commercial or industrial setting:
Bruker S1 Titan 600:
- Cost: $25,000 (verified 1/30/2019)
- Weight: 3 lbs
Courtesy of www.bruker.com
Thermo Scientific Niton™ XL5 Handheld XRF Analyzer
- Cost: $30,000 (verified 1/30/2019)
- Weight: 3 lbs
Courtesy of Thermo Scientific
Olympus Vanta Handheld XRF
- Cost: $20,000 (verified 1/30/2019)
- Weight: 4 lbs
Photo used with permission from Olympus
How Risks are Reduced:
In order to know if there is a potential for lead exposure, workers must first know if the material they are working with contains lead. Using a hXRF gun is a quick and accurate way to determine the lead content of the material you are going to be sanding, scraping, welding, or blasting. Once workers know if lead is present, their employers can take steps to substitute a different material, use an engineering control like local exhaust ventilation or a water spray, or provide personal protective equipment that prevents lead exposure.
Traditional sampling for lead-based paint requires the removal of paint chips to be sent to a lab for analysis, which can take several weeks. DIY lead swab kits are available, but they are imprecise, prone to false positives, may miss lead paint that has been covered by newer layers of lead-free paint, and can only be used on certain colors of paint. hXRF guns provide real-time readings in minutes or seconds, ensuring that workers are aware of and protected from the hazards of lead inhalation or ingestion throughout the entire project lifecycle.
Effects on Productivity:
Using a hXRF gun gives the user nearly instantaneous readings, eliminating the need to wait for third-party sample analysis or pay lab fees. There is a much lower risk of damaging the workpiece since there is no need to scrape or cut off samples. This also reduces the risk of coming in contact with lead during the sampling process. Although hXRF guns can be expensive to purchase and maintain, many manufacturers offer rentals. You can also hire a certified person with their own unit to take measurements for you.
hXRF guns emit radiation and operators must have special training and permits. This training is sometimes available through the manufacturer. In some cases, state or federal certification is required when conducting lead hazard evaluations or inspections. You should never hold the substance being analyzed in your hand or point the gun at other people or yourself. Although hXRF is generally fairly accurate, some materials can interfere with readings, so it’s a good idea to confirm results by sending a small sample to an accredited lab for analysis.
The models listed above are appropriate for industrial and commercial applications, but are not certified by the US Department of Housing and Urban Development (HUD) for use in residential inspection. hXRF units used for residential inspection and abatement purposes must have a Performance Characteristic Sheet.
Sara Brooks, MPH - CPWR - The Center for Construction Research and Training
Bruce Lippy, Ph.D., CIH, CSP, FAIHA - CPWR - The Center for Construction Research and Training
Michael R. Cooper, CIH, CSP, MPH