What does external dose refer to?

External dose refers to the amount of radiation absorbed by the body from sources outside the body. This encompasses various forms of radiation, including gamma rays, X-rays, and neutron radiation that can penetrate the body from external sources, potentially causing biological effects. It is critical for radiation workers to monitor their external dose, as it can help assess exposure risks and ensure safety protocols are being followed.

The other options describe different concepts: radiation from internal sources pertains to contamination that occurs when radioactive materials enter the body; limited skin exposure focuses only on the radiation impacting the outermost layer of the skin; while radiation from natural background sources refers to radiation that originates from the environment, not specifically to the dosage absorbed externally. Each of these distinctions is important in understanding the broader context of radiation exposure and safety measures.