Radiation Quantities and Units
SI derived units with special names and symbols admitted for reasons of
safeguarding human health.a This table is largely taken from
Guide for the Use of the International
System of Units (SI). NIST Special Publication (SP) 811, 1995 Edition,
U.S. Department of Commerce, National Institute of Standards and Technology,
Gaithersburg, MD 20899.
| Derived quantity |
SI derived unit |
Special
name |
Special
symbol |
Expression in
terms of other
SI units |
Expression in
terms of SI
base units |
|---|
| activity (of a radionuclide) |
becquerel |
Bq |
|
s-1 |
absorbed dose
specific energy (imparted),
kerma,
cema |
gray |
Gy |
J/kg |
m2·s-2 |
dose equivalent,
ambient dose equivalent,
directional dose equivalent,
personal dose equivalent |
sievert |
Sv |
J/kg |
m2·s-2 |
| a |
The derived quantities to be expressed in the gray and the
sievert have been revised in accordance with the recommendations of the
International Commission of Radiation Units and Measurements (ICRU). (See:
Radiation Quantities and Units, ICRU Report 33, 1980; and
Quantities and Units in Radiation Protection and Dosimetry, ICRU
Report 51, 1993; Conversion Coefficients for Use in Radiological
Protection Against External Radiation, ICRU Report 57, 1998;
Radiation Quantities and Units, ICRU Report 60, 1998. |
Ionizing Radiation
Division
 
Inquiries or comments:
lisa.karam@nist.gov
Online: June 1996 - Last update: July 2003
|
