Background and Purpose: EBT4 Radiochromic films (RCFs) are replacing the well-described EBT3 type.This study aimed to benchmark the EBT4 type against its predecessor for photon (kV and MV) and proton beam dosimetry.Materials and Methods: Differences between the film types regarding the signal-to-noise ratio (SNR) were investigated in 6 MV photon and 148.2 MeV proton beams in the dose range of 0.2 Gy to 10 Gy for all RGB channels.The effect of the dose-averaged linear energy transfer (LET d ) on the response of both film types was compared within a proton spread-out Bragg peak (SOBP).Furthermore, the relative response in low-kV X-rays was studied and the effect of long-term storage on both film types.
Kuess et al. (Fri,) studied this question.