Texas Industrial Radiography Gamma Practice Test

What dose would you receive if you stood at a location with a survey instrument reading of 100 mr/hr for 6 minutes?

1. 10 mrem

2. 25 mrem

3. 6 mrem

4. 60 mrem

The correct answer is: 10 mrem

To calculate the dose received in this scenario, it's important to understand how to convert the survey instrument reading and the exposure time into a dose. The survey reading indicates the dose rate, which in this case is 100 milliroentgen per hour (mr/hr). First, convert the time from minutes to hours: 6 minutes is equivalent to 0.1 hours (since 6 minutes divided by 60 minutes per hour equals 0.1 hours). Now, using the dose rate, we can calculate the dose received during that time period: Dose (in mrem) = Dose rate (in mr/hr) × Time (in hours). So, using the provided numbers: Dose = 100 mr/hr × 0.1 hr = 10 mrem. This shows that the dose received at a location with a survey instrument reading of 100 mr/hr over a duration of 6 minutes is indeed 10 mrem. The calculation demonstrates that when consistently applying the units and conversion factors, the correct conclusion leads to a dose of 10 mrem, validating that the answer provided aligns with the expected results in this type of radiographic scenario.