Which statement best describes ALARA in practice?

Which statement best describes ALARA in practice?

• A. Increase time to reduce shielding needs
• B. Use no shielding if exposure is low
• C. Use time, distance, and shielding to reduce exposure
• D. Ignore monitoring when exposure is low

Answer: (C)

ALARA means keeping radiation doses as low as reasonably achievable by using three practical controls: time, distance, and shielding. By reducing the time you spend near the source, you limit the total exposure accrued. Increasing the distance from the source dramatically reduces dose because radiation intensity drops quickly with distance, so you plan measurements to maximize distance whenever possible or use remote readouts. Proper shielding is designed to absorb or block radiation, so keeping the gauge shielded when not actively taking measurements and using appropriate barriers minimizes exposure for everyone nearby. In practice for nuclear gauge work, you would keep the source in its shielded position whenever possible, perform only the necessary measurement tasks in as short a time as needed, and maintain as much distance as feasible from the source during operation. You’d also rely on monitoring to confirm exposure stays within limits and to guide any adjustments. The other options don't fit ALARA because they either ignore shielding, skip monitoring, or unnecessarily increase time spent near the source, which would raise, not lower, exposure.

ALARA means keeping radiation doses as low as reasonably achievable by using three practical controls: time, distance, and shielding. By reducing the time you spend near the source, you limit the total exposure accrued. Increasing the distance from the source dramatically reduces dose because radiation intensity drops quickly with distance, so you plan measurements to maximize distance whenever possible or use remote readouts. Proper shielding is designed to absorb or block radiation, so keeping the gauge shielded when not actively taking measurements and using appropriate barriers minimizes exposure for everyone nearby.

In practice for nuclear gauge work, you would keep the source in its shielded position whenever possible, perform only the necessary measurement tasks in as short a time as needed, and maintain as much distance as feasible from the source during operation. You’d also rely on monitoring to confirm exposure stays within limits and to guide any adjustments.

The other options don't fit ALARA because they either ignore shielding, skip monitoring, or unnecessarily increase time spent near the source, which would raise, not lower, exposure.