1 A 137Cs source generates 730 mrem of radiation If it is pl

1. A ¹³⁷Cs source generates 73.0 mrem of radiation. If it is placed in a steel box that is 2.1 in in thickness, what will be the level of radiation outside the box? Round your answer to the nearest tenth of a mrem.

2.   During an 8-hour work day, a worker is exposed to three different hazardous substances, A, B and C. The allowable 8-hour exposures are 3.0, 46.0, and 671.0 ppm, respectively. The exposure levels are 1.38, 10.2, and 100.0 ppm, respectively.Assuming there are no interactions and effects are additive, what is the total effect ratio (X)? State your answer rounded to two decimal places.

3. You evaluate a worker\'s exposure to hazardous materials on the job and everything seems OK, but the worker is showing signs of illness which may be due to exposure to hazardous materials. What two questions might you ask the worker to try to find a likely source of his illness? Why?

Solution

Question -1

I =Ioe^-(mu)X

Io= 73 mrem= 0.73rad
x=2.1 inch= 5.27 cm

for Cs -137, we know that mu= mu_o X density
       = (0.114 cm^2 ) X (11.35gm/cm^3) = 1.29 cm^-1
      

There fore Radiation out side box of 2.1 inch will be gven as,
I = Ioe^-(mu)X = 0.081 mrem.