Test Methodology for Accessible Lead in Vinyl Products*

Materials and Reagents:

1. Nitric Acid, Trace Metal Grade
2. Glass Test Tubes
3. Filter Paper - 55mm diameter, No. 2 filters
4. Pre-wetted Wipes (optional)
5. Hot Plate
6. Distilled Water
7. Certified reference lead standard.

Procedures:

For each of 3 separate #2 filter papers of 55mm diameter, weigh the filter paper and wet it with the same weight (±10%) of distilled water, or use similar commercial pre-wetted wipes, such as Ghost™ wipe. Gently wipe each filter 10 times over a known, intact surface area on the item being tested. Wiping is done in one direction over the surface. Wipe same area each time with each wipe (10 times each with 3 wipes for a total of 30 strokes over the area). If sample is sufficiently large, use 100cm² area; for smaller samples use less, but record area used.

Digest the filter papers individually in concentrated nitric acid at reflux conditions for 6 hours. Analyze digested samples for lead concentration by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), Flame Atomic Absorption Spectrometry (FAAS), or Graphite Furnace Atomic Absorption Spectrometry (GFAAS) Techniques following methodology found in ASTM E 1613.

The results for accessible metal wiped from the surface are summed and divided by the total number of wipes and expressed as the average micrograms per 100cm² per wipe (µg/100cm²/wipe).

Use good laboratory practices for calibration, method blank, quality control checks, and detection limits.

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*This methodology was developed by CPSC staff, has not been reviewed or approved by, and may not reflect the views of, the Commission.