What is bioassay in the context of radiological safety?

Bioassay, in the context of radiological safety, refers to a method used to evaluate internal contamination with radioactive materials by analyzing biological samples from individuals. This process typically involves collecting samples such as urine, feces, or blood to detect and quantify radioactive isotopes that may have entered the body.

The significance of bioassay lies in its ability to provide critical information about the potential health risks posed by internal radiation exposure. By assessing the levels of radioisotopes in biological samples, safety and health professionals can determine whether an individual has been exposed to radioactive substances and take appropriate actions, such as medical intervention or decontamination if necessary.

In comparing this to the other options, external radiation measurement is concerned with assessing the radiation levels in the environment or on surfaces, while radiation shielding techniques focus on methods to protect individuals from radiation exposure. A monitoring device for ambient radiation operates continuously to measure the levels of radiation in a given area but does not specifically analyze biological samples or internal contamination. Thus, bioassay stands out uniquely as an internal assessment method in radiological safety.