Question

The maximum permissible workday dose for occupational exposure to radiation is 18 mrem. A 54-kg laboratory technician absorbs 2.6 mJ of 0.30-MeV gamma rays in a workday. The relative biological effectiveness (RBE) for gamma rays is 1.00. What is the ratio of the equivalent dosage received by the technician to the maximum permissible equivalent dosage?

Answer 1

Answer:

0.267 × 10⁻³

Explanation:

Given:

maximum permissible workday dose  = 18 mrem

Weight of the laboratory technician = 54 kg

gamma rays absorbed = 2.6 mJ of 0.30 MeV

relative biological effectiveness (RBE) for gamma rays = 1.00

Now,

Radiation Absorbed Dose $= \frac{2.6 mJ}{54 kg}\times\frac{1J}{1\times10^3J}\times\frac{1 rad}{0.01 J/kg} = 4.8\times10^{-3}rad$

also,

Roentgen Equivalent Man = rad × Q

here Q is the quality factor = 1 for gamma rays

thus,

Roentgen Equivalent Man = 4.8 × 10⁻³ × 1 = 4.8 × 10⁻³ rem

Therefore,

the ratio of the equivalent dosage received by the technician to the maximum permissible equivalent dosage will be

= $\frac{4.8\times10^{-3}}{18}$

or

= 0.267 × 10⁻³