View source for Physics:Deep-dose equivalent

The '''Deep-dose equivalent'''  (DDE) is a measure of external radiation exposure defined by US regulations. It is reported alongside eye and shallow dose equivalents on typical US dosimetry reports. It represents the dose equivalent at a tissue depth of 1&nbsp;cm (1000&nbsp;mg/cm2) due to external whole-body exposure to [[Physics:Ionizing radiation|ionizing radiation]].<ref>{{cite book|title=10 CFR 20.1003|year=2009|publisher=US Nuclear Regulatory Commission|url=https://www.nrc.gov/reading-rm/doc-collections/cfr/part020/part020-1003.html}}</ref>
Dose due to external radiation tends to decrease with depth because of the shielding effects of outer tissues. The reference depth of 1&nbsp;cm essentially discounts alpha and beta radiation that are easily shielded by the skin, clothing, and bone surface, while taking minimal credit for any self-shielding from the more penetrating gamma rays. This makes the deep-dose equivalent a conservative measure of internal organ exposure to external radiation, while eye and skin exposure to external radiation must be accounted differently. Deep-dose equivalent does include any contribution from internal contamination.

==See also==

*Radioactivity
*Radiation poisoning
*[[Physics:Ionizing radiation|Ionizing radiation]]
*[[Physics:Dosimetry|Dosimetry]]
*[[Physics:Absorbed dose|Absorbed dose]]
*[[Physics:Total effective dose equivalent|Total effective dose equivalent]]
*[[Physics:Collective dose|Collective dose]]
*[[Physics:Cumulative dose|Cumulative dose]]
*[[Physics:Committed dose equivalent|Committed dose equivalent]]
*Committed effective dose equivalent

==References==
{{Reflist}}
*[https://www.nrc.gov/reading-rm/basic-ref/glossary/deep-dose-equivalent-dde.html USNRC glossary]

==External links==
* [https://web.archive.org/web/20161221205248/http://www.wmsym.org/archives/2009/pdfs/9444.pdf] - "The confusing world of radiation dosimetry" - M.A. Boyd, 2009, U.S. Environmental Protection Agency. An account of chronological differences between USA and ICRP dosimetry systems.

{{Radiation}}

[[Category:Radioactivity]]
[[Category:Radiation health effects]]
[[Category:Equivalent units]]



{{Sourceattribution|Deep-dose equivalent}}