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Appendix 36 - Radiation units
| Type of Radiation |
Radiation Weighting Factor |
| Beta Gamma &
X-ray emissions |
1
|
| Neutrons |
5-20
|
| Protons |
5
|
| Alpha particles |
20
|
Summary of Units
| Quantity |
New SI Unit |
Old Unit |
| Activity |
Becquerel - Bq (1disintegration s-1) |
Curie - Ci (3.7 x 1010 dps) |
| Absorbed Dose |
Dose Gray - Gy ( 1 J.kg-1) |
Rad - (0.01 J.kg-1) |
| Equivalent Dose |
Sievert - Sv (Gy x weighting factor) |
Rem - (rad x weighting factor ) |
Prefixes used with SI Units
| Factor |
Prefix |
Symbol |
| 1012 |
Tera |
T
|
| 109 |
Giga |
G
|
| 106 |
Mega |
M
|
| 103 |
Kilo |
K
|
| 10-3 |
Milli |
m
|
| 10-6 |
Micro |
µ |
| 10-9 |
Nano |
n
|
Some useful conversions
| Dose |
Activity |
| 1 Sv = 100rem |
1 µCi = 37 kBq |
| 50mSv = 5 rem |
1 mCi = 37 MBq |
| 200 µSv = 20 mrem |
1 Ci = 37GBq |
| 7.5 µSv.h-1 =0.75mrem.h-1 |
1 kBq = 27 nCi |
|
1 MBq = 27 µCi |
|
1 GBq = 27 mCi |
