HAZMAT Technician Practice Exam

Which unit relates to the exposure rate of ionizing radiation?

1. rem/h

2. mSv/h

3. Gy/h

4. rad/s

The correct answer is: rem/h

The unit that relates to the exposure rate of ionizing radiation is rem/h. Rem, or roentgen equivalent man, is a unit used to measure the biological effect of ionizing radiation on human tissue. When expressed as rem/h, it indicates the rate at which individuals are exposed to radiation over time, providing important information about potential biological effects and health risks associated with that exposure. While millisievert per hour (mSv/h) is also a unit that measures radiation dose for biological effects, rem is specifically used in this context to illustrate how much exposure a person receives in a given timeframe and to assess risk in occupational settings. Gy/h, or gray per hour, measures absorbed dose but does not account for biological effect, and rad/s does not properly reflect the common units used for the exposure rate over a specific duration.