The U. S. Environmental Protection Agency's (USEPA's) Office of Ground Water and
Drinking Water Technical Support Center (TSC) has developed an update to the calculator for
determining the quantitation level, known as the Lowest Concentration Minimum Reporting
Level (LCMRL). The LCMRL is a multi-concentration procedure where the lowest true
concentration for which future recovery is predicted with high confidence (99%), to be between
50 and 150% recovery. The procedure takes into account precision and accuracy at the same
time. It was implemented for the first time by TSC in conjunction with the second cycle of the
Unregulated Contaminant Monitoring Rule and made available online by USEPA. Goals for the
revised procedure included making it more robust and easier to use without creating an additional
burden on the laboratory community. This was accomplished by including a new variance
model that covers all cases of variance and by incorporating nonlinear mean regression models.
Although the new calculator is based on a more rigorous statistical approach, the user interface
has been kept simple and user-friendly. The new approach handles a wider range of real world
situations and met the improvement goals for the project. Includes 4 references, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 940 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 9 |
| Published : | 11/01/2008 |
