TABLE 3.
Approximate values of rLCPE for typical clinical photon energies. The FWHM values represent the smallest field size that can be confidently measured for two representative detector sizes without special small field dosimetry considerations or verifications
| %dd(10,10)x | Representative Photon Energy (MV) a | (cm) | Minimum FWHM for representative 7 mm largest external dimension (cm) | Minimum FWHM for representative 3 mm largest external dimension (cm) |
|---|---|---|---|---|
| 66 | 6 | 1.0 | 2.7 | 2.3 |
| 73 | 10 | 1.6 | 3.9 | 3.5 |
| 77 | 15 | 1.9 | 4.5 | 4.1 |
| 80 | 18 | 2.1 | 4.9 | 4.5 |
| 63 | 6FFF | 0.8 | 2.3 | 1.9 |
| 71 | 10FFF | 1.4 | 3.5 | 3.1 |
a
FF refers to a flattening filter free beam.