RADIOLOGICAL UNITS


    Reference: http://www.orcbs.msu.edu/radiation/radmanual(html)/appendixunits.html
    UnitSymbolBrief DescriptionUse
    CurieCi3.7 x 1010 disintegrations per second (2.22 x 1012 DPM)Special unit of activity
    BecquerelBq1 disintegration per secondSI unit of activity
    RoentgenR2.58 x 10-4 C/kg. (photons in air)Special unit of exposure; applies only to gamma and x radiation
    Radrad0.01 J/kg (100 ergs/g)Special dose unit; applies to any radiation
    GrayGy1 J/kg.SI unit of dose (Equals 100 rads)
    Dose EquivalentHDose x Q x any other modifying factorsRadiation protection
    Quality FactorQBiological effectiveness related to type of radiationRadiation protection
    RemremRad dose x Q x any other modifying factorsSpecial unit of human dose equivalent
    SievertSvGy x Q x any other modifying factorsSI unit of human dose equivalent (Equals 100 rem)

    RELATIONSHIP BETWEEN SPECIAL AND SI UNITS

    Activity:1 Ci = 3.7 x 1010 Bq = 2.22 x 1012 DPM
    Exposure:1 R = 2.58 x 10-4 C/kg.
    The special unit for exposure is the Roentgen. There is no SI unit for exposure; it is simply expressed in C/kg.
    Dose:100 rads = 1 Gy
    Dose Equivalent:100 rems = 1 Sv
    KeV:Kilo (1000) electron volts
    MeV:Mega (1,000,000) electron volts
    1 MeV = 1000 keV
    1 KeV = .001 MeV
    1 Ci = 3.7 x 1010 Bq = 37 GBq
    27 uCi = 1 x 106 Bq = 1 MBq
    1 rad = 0.01 Gy = 10 mGy
    1 rem = 0.01 Sv = 10 mSv

    File: radunits.html

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