Science Buddies: "Ask an Expert"

I'm building a cloud chamber for my science fair project (project link below) to observe ionizing particle interactions. I'd like to be able to convert my frequency measurements (e.g. # beta particles/hr) to an approximate background radiation exposure (dosage in millirems). Is this possible and how can I do it?

https://www.sciencebuddies.org/science- ... ud-chamber

Thank you!

Hi Altair2005,

Your cloud chamber frequency data refer to the amount of radiation released from your material per unit time. Dose equivalent (millirems or other units of measure) refers to the amount and medical effects of absorbed radiation. So the conversion is you're asking about is not a unit conversion and must include other considerations. I must say that this topic is outside my expertise and I'm not sure that the conversion you suggest would be meaningful.

I did find one online reference that shows a calculation of exposure rate (in roentgens) from radiation rate (disintegrations per second) but this is not the same as dose equivalent (in rems):

http://hps.org/publicinformation/ate/fa ... osure.html

You may find this background information useful for sorting though radiation measurement terminology:

https://www.nrc.gov/about-nrc/radiation ... ation.html

I hope this helps. Please ask again if you have more questions.

A. Norman