Editing Background radiation (section)

==Background dose rate examples==

Background radiation varies with location and time, and the following table gives examples:

{| class="wikitable" style="text-align:center"
|- style="background:#ececec;"
|+ Average annual human exposure to ionizing radiation in [[millisievert]]s (mSv) per year
|-
! Radiation source !! World<ref name="UNSCEAR2008">{{cite book |author=United Nations Scientific Committee on the Effects of Atomic Radiation|title=Sources and effects of ionizing radiation |date=2008 |publication-date=2010 |publisher=United Nations |location=New York |isbn=978-92-1-142274-0 |url=http://www.unscear.org/unscear/en/publications/2008_1.html |access-date=9 November 2012|page=4}}</ref>
! US<ref name="NCRP106">{{cite book|title=Ionizing radiation exposure of the population of the United States|year=2009|publisher=National Council on Radiation Protection and Measurements|location=Bethesda, Md.|isbn=978-0-929600-98-7|id=NCRP No. 160|url=http://www.ncrppublications.org/Reports/160|access-date=9 November 2012|archive-date=2 February 2014|archive-url=https://web.archive.org/web/20140202092721/http://www.ncrppublications.org/Reports/160|url-status=dead}}</ref>
! Japan<ref>Ministry of Education, Culture, Sports, Science, and Technology of Japan [http://www.kankyo-hoshano.go.jp/04/04-1.html "Radiation in environment"] {{Webarchive|url=https://web.archive.org/web/20110322231148/http://www.kankyo-hoshano.go.jp/04/04-1.html |date=22 March 2011 }} retrieved 2011-6-29</ref>
! Remark
|-
| Inhalation of air || 1.26 || 2.28 || 0.40 || <small>mainly from [[radon]], depends on indoor accumulation</small>
|-
| Ingestion of food & water || 0.29 || 0.28 || 0.40 || <small>([[potassium-40]], [[carbon-14]], etc.)</small>
|-
| Terrestrial background radiation from ground || 0.48 || 0.21 || 0.40 || <small>depends on soil and building material</small>
|-
| Cosmic radiation from space || 0.39 || 0.33 || 0.30 || <small>depends on altitude</small>
|- style="border-bottom: 3px solid grey;"
| '''sub total (natural)''' || 2.40 || 3.10 || 1.50 || <small>sizeable population groups receive 10–20&nbsp;mSv</small>
|-
| Medical || 0.60 || 3.00 || 2.30 || <small>worldwide figure excludes [[radiotherapy]]; <br />US figure is mostly [[CT scan]]s and [[nuclear medicine]].</small>
|-
| Consumer items || – || 0.13 || || <small>cigarettes, air travel, building materials, etc.</small>
|-
| Atmospheric nuclear testing || 0.005 || – || 0.01 || <small>peak of 0.11&nbsp;mSv in 1963 and declining since; higher near sites</small>
|-
| Occupational exposure || 0.005 || 0.005 || 0.01 || <small>worldwide average to workers only is 0.7&nbsp;mSv, mostly due to radon in mines;<ref name=UNSCEAR2008 /> <br />US is mostly due to medical and aviation workers.<ref name=NCRP106 /></small>
|-
| Chernobyl accident || 0.002 || – || 0.01 || <small>peak of 0.04&nbsp;mSv in 1986 and declining since; higher near site</small>
|-
| Nuclear fuel cycle || 0.0002 || || 0.001|| <small>up to 0.02&nbsp;mSv near sites; excludes occupational exposure</small>
|-
| Other || – || 0.003 || || <small>Industrial, security, medical, educational, and research</small>
|- style="border-bottom: 3px solid grey;"
| '''sub total (artificial)''' || 0.61 || 3.14 || 2.33 ||
|-
| '''Total''' || 3.01 || 6.24 || 3.83 || '''millisieverts per year'''
|}