PLM Laboratory Instruction Memo
Date
TO:I Deal Laboratory
FROM:As Best As Inspector
SUBJECT:Analysis of samples included with this memorandum
A. General Comments
1. The analysis method must be 40 CFR 763 Subpart E, Appendix E, Section 1, PLM and in accordance with 40 CFR 61 Subpart M and EPA clarifications of that rule.
2. The analysis sheet indicates whether the material is categorized as EPA friable (F) or nonfriable (N) material.
3. Grouped samples are packed together, sequentially numbered and identified as such on the analysis sheet.
4.These special terms are used in the Procedural section below:
a. A positive sample is one which has more than 3% asbestos fiber by PLM.
b. A nondetect sample is one in which no asbestos fiber is seen under the PLM.
c. A negative sample is one in which ordinary PLM shows no more than 1% asbestos fiber content.
d. The worst-case sample is the sample which--by ordinary PLM--has the highest apparent asbestos concentration within its group of samples.
B. Procedural
1.Analyze grouped samples sequentially, as a single batch in order as numbered.
2. Initially analyze each batch of multilayer samples as though they were single-layer sample (using the procedures in EPA/600_93/116, Section 2.3 and the recommendations in Appendix D). If the material is nondetect or exceeds 3%, report without further analysis. Otherwise, re-analyze the batch by separating and analyzing each layer separately and determine how to report by the decision principles in Item 3 below.
3. Unless otherwise noted, analyze a group until two (2) positive samples are found or until all samples (not marked hold) in the group have been analyzed.
a.If any positive samples are found in a batch, report without further analysis.
b.Otherwise,
1) for batches of F (friable) materials without any positives:
a) if all samples are nondetect, report without further analysis.
b) otherwise, analyze the worst case sample from the group using point-counting PLM and report without further analysis.
2)for batches of N (not friable) materials without any positives:
a) if all samples are negative, report without further analysis.
b) otherwise, analyze the worst case sample from the group using point-counting PLM and report without further analysis.
Environmental Management Institute Copyright ©2018 page 1
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