X-ray fluorescence (XRF) is a non-destructive process commonly used to determine the elemental configuration of materials. It can be used to identify hazardous substances used in medical device manufacturing, helping companies comply with evolving regulations such as Restriction of Hazardous Substances (RoHS) regulations.
How Does X-Ray Fluorescence Work?
When X-rays are irradiated, they impact the inner-shell electrons of the constituent atoms and move them in the direction of an outer shell. The outer shell electrons then rush toward the inner shells to take the place of the gaps.
X-ray fluorescence technology encompasses the release of these distinctive secondary X-rays. The secondary X-rays can be found in a substance that has been stimulated by high-energy X-rays (or gamma rays).
One of the main benefits of the XRF is that it is a non-destructive testing process. Analysts can evade damage to the assets they examine; therefore, they are able to find more defects. In addition, the non-destructive method is usually less expensive. Other processes can be costly because the product is wasted in the testing stages.
How Is XRF Technology Compliant with Medical Device Manufacturing Criteria?
Medical manufacturers strive to build the safest products. They conduct the most-reliable methods for screening, testing, and verifying in order to be compliant with RoHS regulations. These regulations are constantly changing as new information is revealed about hazards.
The RoHS Directive identifies substances that are restricted, including:
- Bis (2-ethylhexyl) phthalate (DEHP)
- Butyl benzyl phthalate (BBP)
- Dibutyl phthalate (DBP)
- Diisobutyl phthalate (DIBP)
- Hexavalent chromium
- Polybrominated biphenyls (PBB)
- Polybrominated diphenyl ethers (PBDE)
California also has restrictions and requirements similar to the RoHS. They state that all electronic products sold in California must meet the same criteria as those sold in the European Union.
Furthermore, manufacturers of electronic goods must also have reliable verification methods compliant with RoHS regulations. This includes all equipment used for testing and screening. An update to the RoHS (also known as RoHS II, RoHS Recast, or Medical RoHS) states that certain medical devices, cables, monitoring equipment, and control instruments must pass the maximum concentrations of hazardous substances described in the original RoHS criteria. For example, the RoHS and RoHS II regulations must be met when producing halogen-free, flame-retardant products, such as furniture and consumer electronics.
The RoHS regulations continue to change as more data becomes available about the hidden hazards of commonly used products. XRF technology can help lighten this burden. XRF analyzers are well within regulation regarding hazardous substances, and the analyzers themselves help identify hazardous substances, too. Therefore, XRF technology can keep up with these evolving regulations and help verify compliance in all manufacturing stages. Fischer XRF analyzers are remarkably accurate in detecting five common hazardous substances prohibited by the RoHS, including bromine and chlorine.
Handheld XRF Screening
Handheld XRF screening in electronic products and equipment is quick, cost effective, and simple to use. Key toxic elements can be detected by XRF screenings, such as mercury (Hg), lead (Pb), bromine (Br), cadmium (Cd), and chromium (Cr). Because handheld XRF screening is convenient and precise, medical device manufacturers employ this practical method in their testing plan for the RoHS-2 Directive compliance.
The RoHS Directive requirements are rigorous, too. Electronic medical devices imported to the European Union cannot contain Cd levels over 0.01%, and certain compounds of Br and any Pb, Hg, Cr6+ at 0.1%. The detection limits for handheld XRF analyzers vary, but most of these devices are well within the necessary range to meet or exceed the RoHS compliance screenings. Some testing programs may require advanced configurations of handheld XRF devices to bolster the confidence of testing Cd and Cr in alloy metals, such as steel and solders. Fortunately, this is feasible to accomplish.
Over the years, early developments of RoHS have created a solid base for knowledge about parts containing restricted substances. Another valuable contribution from RoHS compliance is the regular screening of components by most manufacturers as part of routine risk management.