ASNT Industrial Radiography Radiation Safety Practice Test

What transport label is required for a source showing a surface reading of 25 mR?

1. White I

2. Yellow II

3. Yellow III

4. Red IV

The correct answer is: Yellow III

In the context of transporting radioactive materials, the transport label required depends upon the level of radiation emitted by the source. A source that shows a surface reading of 25 mR (millirem) typically indicates a certain level of hazard. A Yellow II label is required for packages that emit radiation levels between 0.1 mR/hr and 1.0 mR/hr at a distance of 1 meter from the package. A Yellow III label is used for sources with a surface reading that exceeds the threshold for Yellow II, specifically when the surface reading is between 1.0 mR/hr and 10.0 mR/hr, and if it meets additional criteria based on transport index (TI) values. In this case, a reading of 25 mR at the surface indicates a significant radiation level that would more effectively correspond with the criteria for a Yellow III label, which is utilized for higher radiation levels, thus ensuring compliance with safety regulations during transport. It's essential to recognize that safety labels are crucial for indicating the potential hazard to handlers and the general public and that transporting materials that emit higher radiation levels necessitates stricter labeling protocols to inform individuals of any potential risks.