放射能は、不安定な原子核が放射によってエネルギーを失うプロセスです。Beckerels（BQ）で測定されます。
1 R = 10,000,000 nGy
1 nGy = 1.0000e-7 R
例:
15 Roentgenをナノグレイに変換します。
15 R = 150,000,000 nGy
| Roentgen | ナノグレイ |
|---|---|
| 0.01 R | 100,000 nGy |
| 0.1 R | 1,000,000 nGy |
| 1 R | 10,000,000 nGy |
| 2 R | 20,000,000 nGy |
| 3 R | 30,000,000 nGy |
| 5 R | 50,000,000 nGy |
| 10 R | 100,000,000 nGy |
| 20 R | 200,000,000 nGy |
| 30 R | 300,000,000 nGy |
| 40 R | 400,000,000 nGy |
| 50 R | 500,000,000 nGy |
| 60 R | 600,000,000 nGy |
| 70 R | 700,000,000 nGy |
| 80 R | 800,000,000 nGy |
| 90 R | 900,000,000 nGy |
| 100 R | 1,000,000,000 nGy |
| 250 R | 2,500,000,000 nGy |
| 500 R | 5,000,000,000 nGy |
| 750 R | 7,500,000,000 nGy |
| 1000 R | 10,000,000,000 nGy |
| 10000 R | 100,000,000,000 nGy |
| 100000 R | 1,000,000,000,000 nGy |
Inayam