The Derived Concentration Guideline Level (DCGL) is a radionuclide-specific surface or volume residual radioactivity level that is related to a concentration or dose or risk criterion. The regulator usually determines this criterion.
The DCGLW is a reference criterion, or radioactivity level for residual radioactivity evenly distributed over a large area.
The DCGLEMC ("EMC" stands for elevated measurement exposure) is used when small areas of elevated radioactivity exist within larger areas.
See, Chapter 2: Overview of the Radiation Survey and Site Investigation Process and Glossary on the MARSSIM Manual download page.