On a survey map, what does the symbol for dose rate in mrem/hr at least 30 cm from the source indicate?

On a survey map, what does the symbol for dose rate in mrem/hr at least 30 cm from the source indicate?

• A. Location of a smear
• B. Dose rate in mrem/hr at least 30 cm from the source
• C. Location of an air sample
• D. Step-off pad location

Answer: (B)

The symbol communicates the radiation intensity measured at a reference distance from the source. On a survey map, this marker means the dose rate value in mrem/hr at least 30 centimeters from the source, not the location of a smear, air sample, or step-off pad. This helps you gauge exposure potential and plan work because dose rate decreases with distance, roughly following the inverse-square relationship. A smear indicates surface contamination sampling, an air sample symbol marks air monitoring, and a step-off pad marks a designated transition area—none of these convey the dose rate at a distance.

The symbol communicates the radiation intensity measured at a reference distance from the source. On a survey map, this marker means the dose rate value in mrem/hr at least 30 centimeters from the source, not the location of a smear, air sample, or step-off pad. This helps you gauge exposure potential and plan work because dose rate decreases with distance, roughly following the inverse-square relationship. A smear indicates surface contamination sampling, an air sample symbol marks air monitoring, and a step-off pad marks a designated transition area—none of these convey the dose rate at a distance.