Radiation Measurement Units - International (SI) System

Immediate conversion to SI units, where practical, has been recommended. Tables give ranges most commonly used. To facilitate calculation, decimals and exponent forms have been avoided, where possible. Note the correct use of capital letters.

The curie (Ci) is replaced by the becquerel (Bq)*
1 kilocurie (kCi) = 37 terabecquerel (TBq)
1 curie (Ci) = 37 gigabecquerel (GBq)
1 millicurie (mCi) = 37 megabecquerel (MBq)
1 microcurie (µCi) = 37 kilobecquerel (kBq)
1 nanocurie (nCi) = 37 becquerel (Bq)
1 picocurie (pCi) = 37 millibecquerel (mBq)

Becquerel (Bq)* replaces the curie (Ci)
1 terabecquerel (TBq) ~ 27 curie (Ci)
1 gigabecquerel (GBq) ~ 27 millicurie (mCi)
1 megabecquerel (MBq) ~ 27 microcurie (µCi)
1 kilobecquerel (kBq) ~ 27 nanocurie (nCi)
1 becquerel (Bq) ~ 27 picocurie (pCi)
                                                                 * 1 Bq = 1s-1

The rad (rad) is replaced by the gray (Gy)
1 kilorad (krad) = 10 gray (Gy)
1 rad (rad) = 10 milligray (mGy)
1 millirad (mrad) = 10 microgray (µGy)
1 microrad (µrad) = 10 nanogray (nGy)
The gray (Gy) replaces the rad (rad)
1 gray (Gy) =100 rad (rad)
1 milligray (mGy) = 100 millirad (mrad)
1 microgray (µGy) = 100 microrad (µrad)
1 nanogray (nGy) = 100 nanorad (nrad)
The roentgen (R) is replaced by coulomb/kg (C/kg)
1 kiloroentgen (kR) ~ 258 millicoulomb/kg (mC/kg)
1 roentgen (R) ~ 258 microcoulomb/kg (µC/kg)
1 milliroentgen (mR) ~ 258 nanocoulomb/kg (nC/kg)
1 microroentgen (µR) ~ 258 picocoulomb/kg (pC/kg)
Coulomb/kg (C/kg) replaces the roentgen (R)
1 coulomb/kg (C/kg) ~ 3876 roentgen (R)
1 millicoulomb/kg (mC/kg) ~ 3876 milliroentgen (mR)
1 microcoulomb/kg (µC/kg) ~ 3876 microroentgen (µR)
1 nanocoulomb/kg (nC/kg) ~ 3876 nanoroentgen (nR)
The rem (rem) is replaced by the sievert (Sv)
1 kilorem (krem) = 10 sievert (Sv)
1 rem (rem) = 10 millisievert (mSv)
1 millirem (mrem) = 10 microsievert (µSv)
1 microrem (µrem) = 10 nanosievert (nSv)
The sievert (Sv) replaces the rem (rem)
1 sievert (Sv) = 100 rem (rem)
1 millisievert (mSv) = 100 millirem (mrem)
1 microsievert (µSv) = 100 microrem (µrem)
1 nanosievert (nSv) = 100 nanorem (nrem)

Table was taken from the National Dosimetry Services, Summer 1999 newsletter