Rad Data Handbook 20.. - Voss Associates
Rad Data Handbook 20.. - Voss Associates
Rad Data Handbook 20.. - Voss Associates
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Shallow Dose Correction Factor<br />
In accordance with 10CFR20 and 10CFR835 deep dose<br />
equivalent shall be used for posting of radiation areas.<br />
Shallow dose equivalent shall be reported separate from deep<br />
dose equivalent. Deep dose equivalent is the sum of the<br />
gamma and neutron deep dose equivalents. Shallow dose<br />
includes low-energy photons and charged particles such as<br />
betas, positrons, and protons. Alpha particles are not<br />
included in shallow dose.<br />
The following applies to vented air ionization chambers with a<br />
window density thickness of 7 mg/cm 2 and a moveable shield<br />
with a density thickness of 1,000 mg/cm 2 .<br />
Determining the need to report a shallow dose;<br />
If the Open Shield Reading divided by the Closed Shield<br />
Reading is equal to or greater than 1.2, then perform a<br />
shallow dose survey.<br />
Calculate the shallow dose rate using this equation;<br />
(Open Shield Reading - Closed Shield Reading) x CF<br />
Obtain the CF (Correction Factor) from experimental or<br />
published data for the specific detector and radiation<br />
source(s).<br />
Typical correction factors for betas range between 2 and 5<br />
(multipliers).<br />
Typical correction factors for low energy photons range<br />
between 0.1 and 1 (multipliers).<br />
Low energy photons that penetrate the closed shield of the ion<br />
chamber and produce a response in the instrument are part of<br />
the “deep” dose.<br />
Shallow Dose Correction Factor<br />
In accordance with 10CFR20 and 10CFR835 deep dose<br />
equivalent shall be used for posting of radiation areas.<br />
Shallow dose equivalent shall be reported separate from deep<br />
dose equivalent. Deep dose equivalent is the sum of the<br />
gamma and neutron deep dose equivalents. Shallow dose<br />
includes low-energy photons and charged particles such as<br />
betas, positrons, and protons. Alpha particles are not<br />
included in shallow dose.<br />
The following applies to vented air ionization chambers with a<br />
window density thickness of 7 mg/cm 2 and a moveable shield<br />
with a density thickness of 1,000 mg/cm 2 .<br />
Determining the need to report a shallow dose;<br />
If the Open Shield Reading divided by the Closed Shield<br />
Reading is equal to or greater than 1.2, then perform a<br />
shallow dose survey.<br />
Calculate the shallow dose rate using this equation;<br />
(Open Shield Reading - Closed Shield Reading) x CF<br />
Obtain the CF (Correction Factor) from experimental or<br />
published data for the specific detector and radiation<br />
source(s).<br />
Typical correction factors for betas range between 2 and 5<br />
(multipliers).<br />
Typical correction factors for low energy photons range<br />
between 0.1 and 1 (multipliers).<br />
Low energy photons that penetrate the closed shield of the ion<br />
chamber and produce a response in the instrument are part of<br />
the “deep” dose.<br />
Shallow Dose Correction Factor<br />
In accordance with 10CFR20 and 10CFR835 deep dose<br />
equivalent shall be used for posting of radiation areas.<br />
Shallow dose equivalent shall be reported separate from deep<br />
dose equivalent. Deep dose equivalent is the sum of the<br />
gamma and neutron deep dose equivalents. Shallow dose<br />
includes low-energy photons and charged particles such as<br />
betas, positrons, and protons. Alpha particles are not<br />
included in shallow dose.<br />
The following applies to vented air ionization chambers with a<br />
window density thickness of 7 mg/cm 2 and a moveable shield<br />
with a density thickness of 1,000 mg/cm 2 .<br />
Determining the need to report a shallow dose;<br />
If the Open Shield Reading divided by the Closed Shield<br />
Reading is equal to or greater than 1.2, then perform a<br />
shallow dose survey.<br />
Calculate the shallow dose rate using this equation;<br />
(Open Shield Reading - Closed Shield Reading) x CF<br />
Obtain the CF (Correction Factor) from experimental or<br />
published data for the specific detector and radiation<br />
source(s).<br />
Typical correction factors for betas range between 2 and 5<br />
(multipliers).<br />
Typical correction factors for low energy photons range<br />
between 0.1 and 1 (multipliers).<br />
Low energy photons that penetrate the closed shield of the ion<br />
chamber and produce a response in the instrument are part of<br />
the “deep” dose.<br />
Shallow Dose Correction Factor<br />
In accordance with 10CFR20 and 10CFR835 deep dose<br />
equivalent shall be used for posting of radiation areas.<br />
Shallow dose equivalent shall be reported separate from deep<br />
dose equivalent. Deep dose equivalent is the sum of the<br />
gamma and neutron deep dose equivalents. Shallow dose<br />
includes low-energy photons and charged particles such as<br />
betas, positrons, and protons. Alpha particles are not<br />
included in shallow dose.<br />
The following applies to vented air ionization chambers with a<br />
window density thickness of 7 mg/cm 2 and a moveable shield<br />
with a density thickness of 1,000 mg/cm 2 .<br />
Determining the need to report a shallow dose;<br />
If the Open Shield Reading divided by the Closed Shield<br />
Reading is equal to or greater than 1.2, then perform a<br />
shallow dose survey.<br />
Calculate the shallow dose rate using this equation;<br />
(Open Shield Reading - Closed Shield Reading) x CF<br />
Obtain the CF (Correction Factor) from experimental or<br />
published data for the specific detector and radiation<br />
source(s).<br />
Typical correction factors for betas range between 2 and 5<br />
(multipliers).<br />
Typical correction factors for low energy photons range<br />
between 0.1 and 1 (multipliers).<br />
Low energy photons that penetrate the closed shield of the ion<br />
chamber and produce a response in the instrument are part of<br />
the “deep” dose.