2000 DAC equals what?

2000 DAC equals what?

• A. 1 ALI
• B. 2 ALI
• C. 0.5 ALI
• D. 1000 ALI

Answer: (A)

Derived Air Concentration (DAC) is the air concentration of radioactive material that, if breathed for the standard work year (about 2000 hours), would deliver the annual limit on intake (ALI). Because ALI represents the maximum yearly intake, the relationship is ALI = 2000 × DAC. Therefore, a DAC value accumulated over 2000 hours reaches the ALI. In other words, 2000 DAC corresponds to the full ALI. This convention helps protect workers by linking the permissible annual intake to a practical breathing period and inhalation rate. The other options would imply different multiples or different exposure durations that don’t match the standard 2000-hour year.

Derived Air Concentration (DAC) is the air concentration of radioactive material that, if breathed for the standard work year (about 2000 hours), would deliver the annual limit on intake (ALI). Because ALI represents the maximum yearly intake, the relationship is ALI = 2000 × DAC. Therefore, a DAC value accumulated over 2000 hours reaches the ALI. In other words, 2000 DAC corresponds to the full ALI. This convention helps protect workers by linking the permissible annual intake to a practical breathing period and inhalation rate. The other options would imply different multiples or different exposure durations that don’t match the standard 2000-hour year.