Date: June 18, 2025
A DoD EDQW memorandum directed DoD ELAP laboratories running EPA Method 1633 to follow the method’s own definition of an analytical sequence rather than the QSM definition, effective immediately. The memo sets out a step-by-step sequence that governs how calibration and QC samples are run for PFAS analysis.
What it means for calibration
For DoD work, the order in which calibration and QC samples are run is now set by Method 1633 itself. Labs should confirm that their sequence templates and run records match before their next assessment.
Source: www.denix.osd.mil
Part of the WLTR Standards Hub. This is a plain-language summary, not regulatory advice. Confirm requirements with your accrediting body. Questions or a different read on this change? Leave a comment below.