放射性是不稳定原子核因辐射失去能量的过程。它以Becquerels（BQ）进行测量。
1 γ = 100 rem
1 rem = 0.01 γ
例子:
将15 伽马辐射转换为REM：
15 γ = 1,500 rem
| 伽马辐射 | REM |
|---|---|
| 0.01 γ | 1 rem |
| 0.1 γ | 10 rem |
| 1 γ | 100 rem |
| 2 γ | 200 rem |
| 3 γ | 300 rem |
| 5 γ | 500 rem |
| 10 γ | 1,000 rem |
| 20 γ | 2,000 rem |
| 30 γ | 3,000 rem |
| 40 γ | 4,000 rem |
| 50 γ | 5,000 rem |
| 60 γ | 6,000 rem |
| 70 γ | 7,000 rem |
| 80 γ | 8,000 rem |
| 90 γ | 9,000 rem |
| 100 γ | 10,000 rem |
| 250 γ | 25,000 rem |
| 500 γ | 50,000 rem |
| 750 γ | 75,000 rem |
| 1000 γ | 100,000 rem |
| 10000 γ | 1,000,000 rem |
| 100000 γ | 10,000,000 rem |
规则