TABLE IV.
Scatter correction factors for 6-MV x-rays (d0 = 10 cm).
| Field size | Total scatter | In-air output | Phantom scatter | |
|---|---|---|---|---|
| Equivalent | correction factor | ratio | factor | |
| square | A/P | S c,p | S c | S p |
| 4.0 | 1.0 | 0.866 | 0.957 | 0.905 |
| 5.0 | 1.25 | 0.895 | 0.968 | 0.925 |
| 6.0 | 1.5 | 0.922 | 0.977 | 0.944 |
| 8.0 | 2.0 | 0.964 | 0.990 | 0.974 |
| 10.0 | 2.5 | 1.000 | 1.000 | 1.000 |
| 12.0 | 3.0 | 1.028 | 1.008 | 1.020 |
| 14.0 | 3.5 | 1.051 | 1.014 | 1.037 |
| 16.0 | 4.0 | 1.070 | 1.018 | 1.051 |
| 20.0 | 5.0 | 1.102 | 1.024 | 1.076 |
| 24.0 | 6.0 | 1.127 | 1.029 | 1.096 |
| 28.0 | 7.0 | 1.149 | 1.034 | 1.111 |
| 32.0 | 8.0 | 1.167 | 1.040 | 1.123 |
| 40.0 | 10.0 | 1.194 | 1.048 | 1.139 |