Table 4.

Width between 50% dose levels at ${\mathrm{d}}_{\text{max}}$ for the 15‐MV photon beam

Field width at $\text{SSD}=100$ cm	Width between 50% dose levels defined by jaws and MLC at $d_{\text{max}}$	Width between 50% dose levels defined by jaws only at $d_{\text{max}}$	Width between 50% dose levels defined by MLC only at $d_{\text{max}}$
40 mm	41.5 mm	41.3 mm	43.5 mm
100 mm	103.0 mm	103.1 mm	105.2 mm
200 mm	206.7 mm	206.9 mm	208.3 mm
300 mm	309.1 mm	310.1 mm	310.9 mm