The impact of photon energy spectrum on dose deposition variability is investigated using dosimetry, charge collection experiments on electronic and opto-electronic devices, and Radiation-Induced Attenuation (RIA) measurements in optical fibers. Geant4 calculations are performed to discuss the influence of photon energy spectrum, sensitive layer thickness and of the irradiated material. Implications for radiation test of electronic and optical equipment are discussed to ensure the effective TID is reached in irradiated devices.