Regulatory Update:
NELAC Fields of Testing Changes

Article written by Tom Coyner, President/Technical Director, Analytical Products Group, Inc.

Complete article from Edition 31 APG eNewsletter

Finally after five years, the NELAC Fields of Testing (FOT) laboratory evaluation criteria are changing. Most importantly, the USEPA evaluation criteria for the WS and WP program have been adjusted to match the new NELAC criteria. APG first reported serious technical flaws in the NELAC and EPA criteria to the Environmental Laboratory Accreditation Board (ELAB) in 2000.

The new criteria were developed by the Fields of Testing sub-committee of the NELAC PT Board during 2003-2004 and adopted by NELAC and USEPA this year. APG actively participated in this effort. The sub-committee developed the new criteria from PT data submitted to NELAC from several of the PT providers for the period 1999 through part of 2004. This involved the regression analysis of thousands of data points and the review of more than 1,500 graphs by the sub-committee, the PT Board, and USEPA. While this was a slow and sometimes difficult process, the resulting evaluation criteria are much more realistic and well-grounded. The sub-committee focused on removing the inequity of the old criteria and balancing the needs of the laboratories and the accrediting authorities.

There were hundreds of changes made to the WS and WP criteria. Many of these were adjustments in concentrations ranges to better reflect the needs of the laboratories. Of course, many of the regression criteria were changed to provide performance limits consistent with the abilities of the laboratories. All of these changes are detailed in the new NELAC FOT tables on the NELAC website.

However, the changes which will have the greatest impact on the laboratories are actually in the footnotes of the tables. Effective June 1, 2005, the True Value of the sample will always be within the acceptance range. This change was made to recognize that while some EPA methods are highly biased, laboratories that modify methods to achieve better recoveries should not fail. On the other end of the recovery issue, however, accrediting authorities are no longer willing to accept zero recovery as acceptable on a sample which does contain the analyte within the required range. Therefore, the lowest acceptable recovery will be 10% of the True Value based upon the new footnotes. This could cause significant problems for many laboratories.

Another major change in the new FOT tables is the addition of an experimental table for both WS and WP. It must be noted that these tables do not impact non-NELAC states. NELAC laboratories are required to run experimental analytes for which they are accredited but their accrediting authority cannot use these evaluations for accreditation until the analytes are added to the routine accreditation table. This requirement is likely to cause some confusion for both laboratories and accrediting authorities alike.