La radioactivité est le processus par lequel un noyau atomique instable perd de l'énergie par rayonnement.Il est mesuré en Becquerels (BQ).
1 Bq = 1,000,000,000 nGy 
1 nGy = 1.0000e-9 Bq 
Exemple: 
Convertir 15 Becquerel en Nanogray:
15 Bq = 15,000,000,000 nGy 
| Becquerel | Nanogray | 
|---|---|
| 0.01 Bq | 10,000,000 nGy | 
| 0.1 Bq | 100,000,000 nGy | 
| 1 Bq | 1,000,000,000 nGy | 
| 2 Bq | 2,000,000,000 nGy | 
| 3 Bq | 3,000,000,000 nGy | 
| 5 Bq | 5,000,000,000 nGy | 
| 10 Bq | 10,000,000,000 nGy | 
| 20 Bq | 20,000,000,000 nGy | 
| 30 Bq | 30,000,000,000 nGy | 
| 40 Bq | 40,000,000,000 nGy | 
| 50 Bq | 50,000,000,000 nGy | 
| 60 Bq | 60,000,000,000 nGy | 
| 70 Bq | 70,000,000,000 nGy | 
| 80 Bq | 80,000,000,000 nGy | 
| 90 Bq | 90,000,000,000 nGy | 
| 100 Bq | 100,000,000,000 nGy | 
| 250 Bq | 250,000,000,000 nGy | 
| 500 Bq | 500,000,000,000 nGy | 
| 750 Bq | 750,000,000,000 nGy | 
| 1000 Bq | 1,000,000,000,000 nGy | 
| 10000 Bq | 9,999,999,999,999.998 nGy | 
| 100000 Bq | 99,999,999,999,999.98 nGy |