Which unit is used on high-range RADIAC scales to indicate exposure?

Which unit is used on high-range RADIAC scales to indicate exposure?

• A. Rem
• B. Roentgen
• C. Sievert
• D. Rad

Answer: (B)

High-range RADIAC scales are designed to show exposure in roentgens because exposure is defined as the ionization produced in air by radiation, and the instrument is calibrated to reflect that ionization level directly. The roentgen is the historical unit tied to ionization in air, making it the most straightforward way to indicate environmental exposure for quick hazard assessment. Rem and sievert measure dose equivalents, which relate to biological effect, not the immediate exposure reading on these meters. Rad represents absorbed dose in matter, not exposure in air. So roentgen is the best fit for indicating exposure on a high-range radiac.

High-range RADIAC scales are designed to show exposure in roentgens because exposure is defined as the ionization produced in air by radiation, and the instrument is calibrated to reflect that ionization level directly. The roentgen is the historical unit tied to ionization in air, making it the most straightforward way to indicate environmental exposure for quick hazard assessment. Rem and sievert measure dose equivalents, which relate to biological effect, not the immediate exposure reading on these meters. Rad represents absorbed dose in matter, not exposure in air. So roentgen is the best fit for indicating exposure on a high-range radiac.