Every manufacturer has its own unique “recipe” for the core materials used in lead-free aprons, making each apron slightly different from others. Think of it like baking a cake—every recipe might include the same basic ingredients, but the proportions and methods can vary, resulting in subtle differences. Similarly, lead-free aprons generally contain combinations of bismuth, tin, and antimony, but the percentage of each material varies between manufacturers.

These materials are chosen because of their ability to block radiation effectively, much like lead does. By using a specific blend of these metals, lead-free aprons are able to provide the necessary protection while being lighter and more flexible than traditional lead-based aprons.