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Beta Dose Rates in rad/hr per mCiMeV 1 cm 10 cm 30 cm 60 cm 90 cm 1.0 m0.15 1,200 1.7 0 0 0 00.25 1,000 2.2 0.1 0 0 00.30 900 3.6 0.1 0 0 00.50 750 5.2 0.4 0.05 0.01 00.75 650 5.0 0.5 0.05 0.01 01.0 550 4.6 0.4 0.1 0 01.25 450 4.3 0.4 0.1 0.04 0.021.50 400 4.0 0.4 0.1 0.04 0.021.75 350 3.4 0.4 0.1 0.04 0.022.00 340 3.6 0.4 0.1 0.04 0.022.25 320 3.3 0.4 0.1 0.04 0.02Beta dose should be treated as a “shallow” dose and shouldnot be summed with “deep” doses. This chart should also beused to determine beta+ doses from positron emitters.Half-value Thickness vs Beta EnergyIsotope Emax (MeV) Half-Value Thickness mg / cm 2C-14 0.156 2Tc-99 0.292 7.5Cl-36 0.714 15Sr/Y-90 0.546 / 2.284 150U-238 Betas from short lived progeny0.191 / 2.281 130P-32 1.710 150Estimate the half-value thickness for a beta emitter.mg/cm 2 = 50 x E 2where E is Emax in MeV for the beta emitterThis equation tends to underestimate the half-valuethickness for low energy betas and overestimate thehalf-value thickness for high energy betas.Beta Dose Rates in rad/hr per mCiMeV 1 cm 10 cm 30 cm 60 cm 90 cm 1.0 m0.15 1,200 1.7 0 0 0 00.25 1,000 2.2 0.1 0 0 00.30 900 3.6 0.1 0 0 00.50 750 5.2 0.4 0.05 0.01 00.75 650 5.0 0.5 0.05 0.01 01.0 550 4.6 0.4 0.1 0 01.25 450 4.3 0.4 0.1 0.04 0.021.50 400 4.0 0.4 0.1 0.04 0.021.75 350 3.4 0.4 0.1 0.04 0.022.00 340 3.6 0.4 0.1 0.04 0.022.25 320 3.3 0.4 0.1 0.04 0.02Beta dose should be treated as a “shallow” dose and shouldnot be summed with “deep” doses. This chart should also beused to determine beta+ doses from positron emitters.Half-value Thickness vs Beta EnergyIsotope Emax (MeV) Half-Value Thickness mg / cm 2C-14 0.156 2Tc-99 0.292 7.5Cl-36 0.714 15Sr/Y-90 0.546 / 2.284 150U-238 Betas from short lived progeny0.191 / 2.281 130P-32 1.710 150Estimate the half-value thickness for a beta emitter.mg/cm 2 = 50 x E 2where E is Emax in MeV for the beta emitterThis equation tends to underestimate the half-valuethickness for low energy betas and overestimate thehalf-value thickness for high energy betas.Beta Dose Rates in rad/hr per mCiMeV 1 cm 10 cm 30 cm 60 cm 90 cm 1.0 m0.15 1,200 1.7 0 0 0 00.25 1,000 2.2 0.1 0 0 00.30 900 3.6 0.1 0 0 00.50 750 5.2 0.4 0.05 0.01 00.75 650 5.0 0.5 0.05 0.01 01.0 550 4.6 0.4 0.1 0 01.25 450 4.3 0.4 0.1 0.04 0.021.50 400 4.0 0.4 0.1 0.04 0.021.75 350 3.4 0.4 0.1 0.04 0.022.00 340 3.6 0.4 0.1 0.04 0.022.25 320 3.3 0.4 0.1 0.04 0.02Beta dose should be treated as a “shallow” dose and shouldnot be summed with “deep” doses. This chart should also beused to determine beta+ doses from positron emitters.Half-value Thickness vs Beta EnergyIsotope Emax (MeV) Half-Value Thickness mg / cm 2C-14 0.156 2Tc-99 0.292 7.5Cl-36 0.714 15Sr/Y-90 0.546 / 2.284 150U-238 Betas from short lived progeny0.191 / 2.281 130P-32 1.710 150Estimate the half-value thickness for a beta emitter.mg/cm 2 = 50 x E 2where E is Emax in MeV for the beta emitterThis equation tends to underestimate the half-valuethickness for low energy betas and overestimate thehalf-value thickness for high energy betas.Beta Dose Rates in rad/hr per mCiMeV 1 cm 10 cm 30 cm 60 cm 90 cm 1.0 m0.15 1,200 1.7 0 0 0 00.25 1,000 2.2 0.1 0 0 00.30 900 3.6 0.1 0 0 00.50 750 5.2 0.4 0.05 0.01 00.75 650 5.0 0.5 0.05 0.01 01.0 550 4.6 0.4 0.1 0 01.25 450 4.3 0.4 0.1 0.04 0.021.50 400 4.0 0.4 0.1 0.04 0.021.75 350 3.4 0.4 0.1 0.04 0.022.00 340 3.6 0.4 0.1 0.04 0.022.25 320 3.3 0.4 0.1 0.04 0.02Beta dose should be treated as a “shallow” dose and shouldnot be summed with “deep” doses. This chart should also beused to determine beta+ doses from positron emitters.Half-value Thickness vs Beta EnergyIsotope Emax (MeV) Half-Value Thickness mg / cm 2C-14 0.156 2Tc-99 0.292 7.5Cl-36 0.714 15Sr/Y-90 0.546 / 2.284 150U-238 Betas from short lived progeny0.191 / 2.281 130P-32 1.710 150Estimate the half-value thickness for a beta emitter.mg/cm 2 = 50 x E 2where E is Emax in MeV for the beta emitterThis equation tends to underestimate the half-valuethickness for low energy betas and overestimate thehalf-value thickness for high energy betas.