HAZMAT Technician Practice Exam

What is the relationship between rad and Gy?

1. 1 rad = 1 mGy

2. 1 rad = 10 mGy

3. 10 rad = 1 Gy

4. 100 rad = 10 Gy

The correct answer is: 1 rad = 10 mGy

The correct understanding of the relationship between rad and Gy lies in their definitions and equivalent values. The rad (radiation absorbed dose) is an older unit used to measure the amount of energy absorbed by a material, whereas the gray (Gy) is the SI unit of absorbed dose. One gray is equivalent to 100 rads. Therefore, if you break down the conversion further, you can calculate that 1 rad equals 0.01 Gy (since 1 Gy = 100 rads). This means that if you were to convert rads to milligrays (mGy), where 1 Gy equals 1,000 mGy, you would find that 1 rad indeed translates to 10 mGy. Therefore, option B accurately reflects this conversion, establishing the correct relationship between rad and Gy by demonstrating that 1 rad can be expressed as 10 mGy.