Relationship between dose rate and amount of radioactive particles

[winnie_t]

Hi,

This might be a silly question but I've been struggling to find this out.

What is the relationship between dose rate and the amount of Cs-137 in an area?

if I know the exposure dose of the area is 5mSv, how can I work out how much Cs-137 is in this area?

Thanks

 

[mfb]

5mSv in what time frame?
In addition, it depends on the location of Cs-137. Is it in the ground, or in the air, or somewhere else? How deep in the ground? ...

For a rough estimate of the activity, you can divide the number of Cs-137-atoms in some volume by the lifetime to get the decays per time and volume. Multiply it with the decay energy to get the released energy per time and volume.

 

[mkarger]

We would need to know the length of time of exposure, the location of the source from the measurement point and any potential medium that the sourced energy must travel through.