What is the concept of "ALARA" in radiation protection?

• A. As Low As Reasonably Achievable; minimize exposure considering economic/social factors.
• B. All Levels Are Readily Achievable; no constraints.
• C. As Low As Required At Any cost; unrealistic.
• D. As Long As Radiation Avoidance remains Active; not standard.

Answer: (A)

ALARA means keeping radiation exposure as low as reasonably achievable by actively reducing dose through a careful balance of benefits, costs, and social factors. The idea is not to eliminate exposure completely or pursue endless reductions, but to optimize protection within practical limits.

In practice, you apply ALARA by looking at how to lower dose using the three classic avenues: time, distance, and shielding. Shorter time near the source, greater distance from the source, and appropriate shielding all help reduce dose. You also layer engineering controls (enclosures, ventilation, interlocks), administrative controls (procedures, rotation of workers, training), and appropriate personal protective equipment when needed. The goal is to continually assess and implement improvements that reduce exposure without causing prohibitive costs or burdens.

Why the other phrasing isn’t correct: the idea that “all levels are readily achievable” ignores real-world limits and costs; the notion of reducing to that level at any cost omits the necessary consideration of economic and social factors; and a concept focused on avoidance rather than optimization isn’t a recognized, standard approach in radiation protection.