RoHS compliance and halogen screening with handheld XRF analysis

Importance of the topic

Regulation of heavy metals and halogenated compounds in electronic equipment is critical for environmental protection and human health. RoHS directives limit toxic substances such as lead, mercury, cadmium, hexavalent chromium, PBB and PBDE, driving the need for rapid, cost-effective screening methods at production and supply chain stages.

Objectives and Study Overview

This application note presents the use of the Thermo Scientific Niton XL5 Plus handheld XRF analyzer for RoHS compliance and halogen screening. It demonstrates the analyzer’s ability to deliver fast, non-destructive testing according to IEC 62321-3-1 and related standards across metals, alloys, ceramics, glass and plastics.

Methodology and Instrumentation

The Niton XL5 Plus features a 5W miniaturized X-ray tube, large-area silicon drift detector with graphene window, and dedicated analysis modes:

• TestAll™ Mode: automatically identifies material type and selects optimal measurement parameters
• Electronic Metals Mode and Plastics Mode: FP-based calibrations for metals and polymers
• Micro and macro cameras for precise spot targeting and visual tagging
• Small spot capability (3 mm) and thickness correction for thin samples
• Customizable pass/fail/inconclusive thresholds aligned with RoHS and halogen-free standards

The analyzer can operate in handheld or portable test stand configurations for enhanced stability and lab-like conditions.

Key Results and Discussion

Screening of homogeneous parts showed reliable classification of compliant, inconclusive or non-compliant samples:

• PCB substrates with high bromine content flagged as inconclusive pending lab confirmation
• Individual solder joints measured for lead content using small spot analysis, detecting non-compliant levels
• Polyethylene pellets screened for total chlorine and bromine, indicating non-halogen-free material when combined halogen sum exceeded thresholds

Detection limits ranged from single-digit ppm for lead and bromine in plastics to tens of ppm for heavy metals in metals and alloys, ensuring best-in-class sensitivity in 60–120 s analyses.

Benefits and Practical Applications

Handheld XRF enables on-site, point-and-shoot screening throughout production, incoming inspection and recycling processes. It reduces reliance on laboratory testing, lowers costs, increases throughput and supports a “trust but verify” quality assurance strategy. The robust design ensures consistent performance regardless of user expertise.

Future Trends and Potential Applications

Advances in detector technology, data processing and complementary techniques will expand screening capabilities for organics, nano-materials and increasingly complex multi-layer assemblies. Integration with digital supply chain systems and AI-driven analytics can further streamline compliance workflows and predictive maintenance of analytical instruments.

Conclusion

The Niton XL5 Plus handheld XRF analyzer offers a powerful, user-friendly solution for rapid RoHS compliance and halogen screening. Its sensitivity, versatility and portability make it an essential tool for manufacturers, regulators and recyclers aiming to meet stringent environmental requirements efficiently.

Reference

• IEC 62321-1:2013, Determination of Certain Substances in Electrotechnical Products
• IEC 62321-3-1, Screening — Lead, Mercury, Cadmium, Total Chromium and Total Bromine by X-ray Fluorescence
• ASTM F2617-15, Identification and Quantification of Cr, Br, Cd, Hg, and Pb in Polymers by EDXRF
• Thermo Fisher Scientific, Enhanced Sensitivity to Detect Phthalates by FT-IR
• Thermo Fisher Scientific, Rapid Determination of Phthalates in Polymers by GC-MS