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Nuclear Radiation |
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Below, I
present a nuclear radiation detection information
guide. |
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Isotope |
Mev |
Radiation Emitted |
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Light Nuclides |
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6 19 27 38 43 53 55 83 |
Tritium (He3) |
0.155 1.460 0.318 0.546 0.292 0.150 0.514 - |
Beta |
. 12 years |
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Heavy Nuclides |
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86 88 90 92 92 92 94 95 |
Polonium-210 |
4.78 5.49 4.68 4.77 4.39 4.20 5.15 5.49 |
Pure alpha |
138 days . . . . . . . . . . . . . . . . . .
. . . |
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For most people, radon is the biggest threat, due to its accumulation within buildings. Inhaled radon gas causes lung cancer. |
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Ionizing Radiation |
Shielding/ Detection |
Dosage/ Danger |
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Alpha particles (helium nuclei) |
Sheet of paper will shield |
One sievert = 0.05 gray of alpha radiation
(Q=20) |
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Alpha particles (helium nuclei) |
Pancake detector is best |
Alpha emitters are dangerous if inhaled or
eaten. |
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Helium nuclei consist of 2 protons
and 2 neutrons. |
SI = International System of
Dosage Units |
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Detector Sensitivity Scales |
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Rems/Hour |
Sieverts/Hour |
Danger Level after 1 Hour |
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1 |
10 µRems |
0.1 µSv |
Background radiation |
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For years, we were told that low-level radiation won't hurt us. Most scientists now concede that ANY amount of radiation CAN be harmful (there is no minimum threshold, above which damage "occurs"). Ionizing radiation damage is cumulative. Reduce your total exposure, to optimize your health. |
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Geiger |
CPM |
mR/Hour |
Sensitivity |
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1 |
Ludlum 2401P |
500 |
0.15 mR |
3,300 |
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Meter faces will vary by a factor of 80 to 1, in terms of the correspondence between Counts per Minute and milliRems/hour. Some example meter readouts are shown above. Probe sensitivity is the big factor here. A very sensitive probe will require fewer counts to determine mR/hour rates. Put another way, at a given mR/hour rate, more counts will be observed using a very sensitive probe. |
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mR/hr |
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CPM @ mR/hr = 600 |
(Bicron 2000) CPM @ mR/hr = 1,200 |
CPM @ mR/hr = 2,500 |
CPM @ mR/hr = 3,300 |
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0.01 |
6 |
12 |
25 |
33 |
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Trying to provide a direct "CPM to
mR Scale" from the above chart above this one. |
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Natural: |
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Cosmic |
28 mR 200 mR 40 mR |
Sun, quasars |
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295 (82%) |
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Manmade: |
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Diagnostic x-ray |
14 mR 11 mR 2 mR |
10 = 390 mR |
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66 (18%) |
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Average annual total |
360 mRem/year |
360 (100%) |
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Source: University of Rochester, annotated |
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Suggested Annual Occupational Limit - Individual |
5,000 mRem (5R) |
360 above = 7% |
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Suggested Annual Occupational Limit - Pregnant Woman |
500 mRem (0.5R) |
360 above = 72% |
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DISCLAIMER |
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Science Related Summaries |
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Vaughn's Summaries (One-Pagers) ©2006 Vaughn Aubuchon ... All Rights Reserved http://www.vaughns-1-pagers.com This Vaughns Nuclear Radiation Detection Information summary web page was updated on 2007-05-30. |