What is one millionth of a REM referred to as?

One millionth of a REM is referred to as a microrem. The term "micro-" indicates a factor of one millionth (10^-6), making microrem a very small unit of radiation dosage measurement. In this context, the REM (Roentgen Equivalent Man) is a unit used to measure the biological effect of ionizing radiation, and breaking it down into microrem allows for more precise measurements, especially in scenarios where very low doses of radiation may have biological effects. This use of specific prefixes like micro- is common in the metric system to convey varying scales of measurement. Understanding these distinctions is crucial for someone working in hazardous materials and radiation safety, as it helps in accurately gauging exposure levels and implementing appropriate safety measures.