For NESHAP analysis, which statement about trace results is correct?

• A. Trace results are automatically below 1%.
• B. Trace results are reanalyzed using TEM.
• C. Trace results are discarded.
• D. A trace result must be reanalyzed using point counting to treat as less than 1%.

Answer: (D)

Trace results in NESHAP analysis reflect very low asbestos levels, where the screening method’s limits make a precise percentage unreliable. Polarized light microscopy can indicate trace asbestos, but it doesn’t provide a trustworthy quantitative value at those levels. Because of that, the standard practice is to reanalyze the sample with transmission electron microscopy and apply a point-counting method. This approach yields a quantitative estimate of the asbestos content, and if the result comes out at or below 1%, it can be treated as less than 1% for regulatory purposes. So the essential idea is that trace findings must be verified with TEM using point counting to determine whether the amount is below the 1% threshold. Relying on the initial trace result alone isn’t sufficient, and simply discarding the trace or using TEM without point counting wouldn’t meet the required quantitative standard.