# What would be the dose rate of 109 grams of uranium per day/year?

I know that with a Pancake probe that can read alpha you can get up to 30K CPM on a small plate. I ordered a 6" red plate off ebay and measured outside the box when it came in. It registered around 200 CPM on a CDV-700 with the beta shield open set against the box with the plate in it.

I did some calculations and came up with a rough estimate of 109 grams of uranium inside the glaze on the plate. I don't know if it is natural uranium or DU as they were manufactured using both and I lack the proper tools to find out.

Edited question: What would be the estimated dose rate of 109 grams of uranium per day/year?

Thank you for your time and help.

Here is a picture for reference:

• 1) Straight Dope. 2) XKCD Radiation Chart Commented Oct 8, 2015 at 14:10
• Wait - you think betas and alphas are getting through the box? What does your meter read away from the box? Commented Oct 8, 2015 at 14:13
• AFAIK, "dangerous" isn't something quantifiable by physicists. You could ask whether this is a reasonable value from the source given its history, or something along those lines. Commented Oct 8, 2015 at 14:19
• That said, look at the uranium decay chains. Most of the energy is in alphas and betas. Short penetration depths. Most of the photons are pretty low energy, too. I leave my orange salt-shaker (reads tens of counts per second at the top surface on our classroom demonstration counter) in a cardboard box on the other side of my office and don't worry about it because I'm surely getting more dose from the K-40 in the cinder-block walls. Commented Oct 8, 2015 at 14:51
• I'm voting to close this question as off-topic because it's about health risks from radiation not physics Commented Oct 8, 2015 at 15:29