NORM Analysis

Norm Analysis
Naturally Occurring Radioactive Materials (NORM) have always been in the earth’s crust. Thorium, uranium and their decay products are the major sources of radioactivity along with potassium-40. Processing may increase the concentration of these substances. Gamma spectrometry can provide an assessment of a suite of uranium and thorium daughters.

Gamma Spectrometry For Solids

Radionuclide Detection Limit
Thorium-234 0.05 Bq/g
Thorium-230 0.8 Bq/g
Thorium-228 0.1 Bq/g
Radium-228 0.1 Bq/g
Radium-226 0.1 Bq/g
Lead-210 0.1 Bq/g
Potassium-40 1 Bq/g
Uranium-235 0.1 Bq/g

Gamma Spectrometry for Water

Radionuclide Detection Limit
Thorium-234 1 Bq/L
Thorium-230 5 Bq/L
Lead-212 0.1 Bq/L
Radium-228 0.5 Bq/L
Radium-226 1 Bq/L
Lead-210 1 Bq/L
Potassium-40 50 Bq/L
Uranium-235 0.5 Bq/L

* does not meet release limits – more sensitive determinations are required. Norm Analysis

Neutron Activation Analysis for NORM

Radionuclide Water Solids
Uranium-238 0.01 Bq/L 0.01 Bq/g
Thorium-232 0.01 Bq/L 0.01 Bq/g
TOTAL Uranium
& Thorium
0.01 Bq/g


Canadian Guidelines for Management of NORM


Release limits for NORM

See Table 5.1 in section 5.31 of Canadian Guidelines for the Management of NORM

NORM Analysis