ISO 22863-4:2021

Overview

ISO 22863-4:2021 specifies a standardized X‑ray fluorescence (XRF) test method for determining lead (Pb) and lead compounds in pyrotechnic compositions used in fireworks. The method uses energy‑dispersive XRF (EDXRF) to identify and quantify Pb in homogeneous pyrotechnic samples and is part of the ISO 22863 series on fireworks chemical testing.

Key topics and requirements

• Scope and range: Applicable to pyrotechnic compositions with Pb mass fractions between 100 mg/kg and 50 000 mg/kg. For concentrations below 100 mg/kg, alternative analytical methods are required.
• Analytical principle: EDXRF - an X‑ray source irradiates a pelletized sample; emitted characteristic X‑ray photons are measured for element identification and quantification.
• Instrument example: Portable XRF analyzer (e.g., Niton XL3t 900S) or equivalent.
• Sample preparation:
  • Dry sample at (105 ± 5) °C (typically ≥2 h, preferably 4 h), cool in a desiccator until mass is constant.
  • Form a flat, compact pellet to ensure reproducible geometry and detector coupling.
• Calibration: Use NIST reference materials (examples provided in the standard) and construct a calibration curve using linear or quadratic regression relating Pb XRF intensity to Pb concentration.
• Measurement protocol:
  • Warm up and calibrate the analyzer per manufacturer guidance.
  • Analyze pellet for a minimum of 60 s and repeat at three different locations on the pellet.
  • Report Pb content in mg/kg, rounded to the nearest mg/kg (or with up to 3 decimal places depending on range).
• Performance and QA:
  • Accuracy and precision to be estimated via interlaboratory studies; a relative standard deviation of about 25% is commonly accepted for low values with this modified technology.
  • Use of certified reference materials (NIST CRMs) for calibration and verification is mandatory.
• Reporting: Lab identification, date, reference to ISO 22863-4:2021, sample description (per ISO 22863-1), results, and any anomalies.

Applications and users

This standard is intended for:

• Fireworks manufacturers performing quality control and raw‑material screening
• Accredited testing laboratories and conformity assessment bodies
• Regulatory authorities and safety inspectors enforcing chemical limits
• Customs and environmental monitoring labs screening pyrotechnic consignments for lead content

Keywords: ISO 22863-4:2021, fireworks testing, lead analysis, XRF spectrometry, pyrotechnic compositions, EDXRF, NIST reference materials, pellet preparation, calibration.

Related standards

• ISO 22863-1 - Generalities for test methods in the ISO 22863 fireworks series (terminology and sampling guidance).
• Other parts of ISO 22863 cover additional specific chemical tests and procedures within the fireworks testing framework.