What does LET measure in radiation safety?

Linear Energy Transfer (LET) is a crucial concept in radiation safety that measures the amount of energy that radiation transfers to the material it passes through per unit length. This measurement is particularly important because it helps determine the biological impact of different types of radiation on tissues, allowing safety officers to evaluate the potential risks associated with various radiation exposure scenarios.

LET is expressed in units of energy per unit distance, commonly measured in keV/μm (kiloelectronvolts per micrometer). Higher LET values indicate that radiation is depositing more energy into the medium it traverses, which correlates with increased ionization density and a greater likelihood of causing damage to biological tissues. For instance, alpha particles have a high LET, leading to more significant biological effects compared to low LET radiation like gamma rays or X-rays, which are more penetrating but ionize less material.

Understanding LET is integral for radiation safety protocols since it informs the choice of protective measures and helps in assessing the potential health risks associated with exposure to different types of ionizing radiation.