Biomedical Engineering Reference
In-Depth Information
2000 UNSCEAR 2000 Report on sources of radiation exposure, radiation-
associated cancer, and the Chernobyl accident.
2003 Dosimetry System 2002 (DS02) formally approved.
2005 ICRP proposes system of radiological protection consisting of dose con-
straints and dose limits, complimented by optimization.
2007 Final decision expected. ICRP 2007 Recommendations.
1.5
Sources and Levels of Radiation Exposure
The United Nations Scientific Committee on the Effects of Atomic Radiation (UN-
SCEAR) has carried out a comprehensive study and analysis of the presence and ef-
fects of ionizing radiation in today's world. The UNSCEAR 2000 Report (see “Sug-
gested Reading” at the end of the chapter) presents a broad review of the various
sources and levels of radiation exposure worldwide and an assessment of the radi-
ological consequences of the 1986 Chernobyl reactor accident.
Table 1.1, based on information from the Report, summarizes the contributions
that comprise the average annual effective dose of about 2.8 mSv (see Chapter 14)
to an individual. They do not necessarily pertain to any particular person, but
Tab l e 1 . 1
Annual per Capita Effective Doses in Year 2000 from
Natural and Man-Made Sources of Ionizing Radiation
Worldwide
*
Annual Effective
Source
Dose (mSv)
Typical Range (mSv)
Natural Background
External
Cosmic rays
0.4
0.3-1.0
Terrestrial gamma rays
0.5
0.3-0.6
Internal
Inhalation (principally radon)
1.2
0.2-10.
Ingestion
0.3
0.2-0.8
Total
2.4
1-10
Medical (primarily diagnostic X rays)
0.4
0.04-1.0
Man-Made Environmental
Atmospheric nuclear-weapons tests
0.005
Peak was 0.15 in 1963.
Chernobyl accident
0.002
Highest average was 0.04 in
northern hemisphere in 1986.
Nuclear power production
0.0002
See paragraph 34 in Report for
basis of estimate.
* Based on UNSCEAR 2000 Report.
