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5. Air-proportional alpha detectors have a flatter energy vs efficiency response than sealed gas-proportional, alpha scintillator, alpha/beta scintillator, or GM detectors. This is due to several factors. One factor is the typically thinner entrance windows on air-proportional alpha detectors compared to beta detectors and alpha and beta scintillator detectors whereby more of the initial alpha particle energy enters the active volume of the air-proportional compared to other detectors. A second factor is the relatively shallow depth of the air-proportional detector compared to the path length of the alpha particle in air which leads to the alpha pulses being of similar height for any alpha particle energy above a threshold. 6. Alpha particle energy transfer to air 6 MeV alpha particles produce 40,000 Ion Pairs per cm 4 MeV alpha particles produce 55,000 Ion Pairs per cm ù for air is 34 eV per Ion Pair therefore; 6 MeV alpha particles lose 1.18 MeV per cm of air 4 MeV alpha particles lose 1.87 MeV per cm of air Alpha particle range in cm of air at 1 atmosphere R a = 0.56 E (E 4 MeV) a Alpha particles lose about 60 KeV of energy per mm of air at STP. 5. Air-proportional alpha detectors have a flatter energy vs efficiency response than sealed gas-proportional, alpha scintillator, alpha/beta scintillator, or GM detectors. This is due to several factors. One factor is the typically thinner entrance windows on air-proportional alpha detectors compared to beta detectors and alpha and beta scintillator detectors whereby more of the initial alpha particle energy enters the active volume of the air-proportional compared to other detectors. A second factor is the relatively shallow depth of the air-proportional detector compared to the path length of the alpha particle in air which leads to the alpha pulses being of similar height for any alpha particle energy above a threshold. 6. Alpha particle energy transfer to air 6 MeV alpha particles produce 40,000 Ion Pairs per cm 4 MeV alpha particles produce 55,000 Ion Pairs per cm ù for air is 34 eV per Ion Pair therefore; 6 MeV alpha particles lose 1.18 MeV per cm of air 4 MeV alpha particles lose 1.87 MeV per cm of air Alpha particle range in cm of air at 1 atmosphere R a = 0.56 E (E 4 MeV) a Alpha particles lose about 60 KeV of energy per mm of air at STP. Page 125 Page 125 5. Air-proportional alpha detectors have a flatter energy vs efficiency response than sealed gas-proportional, alpha scintillator, alpha/beta scintillator, or GM detectors. This is due to several factors. One factor is the typically thinner entrance windows on air-proportional alpha detectors compared to beta detectors and alpha and beta scintillator detectors whereby more of the initial alpha particle energy enters the active volume of the air-proportional compared to other detectors. A second factor is the relatively shallow depth of the air-proportional detector compared to the path length of the alpha particle in air which leads to the alpha pulses being of similar height for any alpha particle energy above a threshold. 6. Alpha particle energy transfer to air 6 MeV alpha particles produce 40,000 Ion Pairs per cm 4 MeV alpha particles produce 55,000 Ion Pairs per cm ù for air is 34 eV per Ion Pair therefore; 6 MeV alpha particles lose 1.18 MeV per cm of air 4 MeV alpha particles lose 1.87 MeV per cm of air Alpha particle range in cm of air at 1 atmosphere R a = 0.56 E (E 4 MeV) a Alpha particles lose about 60 KeV of energy per mm of air at STP. 5. Air-proportional alpha detectors have a flatter energy vs efficiency response than sealed gas-proportional, alpha scintillator, alpha/beta scintillator, or GM detectors. This is due to several factors. One factor is the typically thinner entrance windows on air-proportional alpha detectors compared to beta detectors and alpha and beta scintillator detectors whereby more of the initial alpha particle energy enters the active volume of the air-proportional compared to other detectors. A second factor is the relatively shallow depth of the air-proportional detector compared to the path length of the alpha particle in air which leads to the alpha pulses being of similar height for any alpha particle energy above a threshold. 6. Alpha particle energy transfer to air 6 MeV alpha particles produce 40,000 Ion Pairs per cm 4 MeV alpha particles produce 55,000 Ion Pairs per cm ù for air is 34 eV per Ion Pair therefore; 6 MeV alpha particles lose 1.18 MeV per cm of air 4 MeV alpha particles lose 1.87 MeV per cm of air Alpha particle range in cm of air at 1 atmosphere R a = 0.56 E (E 4 MeV) a Alpha particles lose about 60 KeV of energy per mm of air at STP. Page 125 Page 125
RULES OF THUMB FOR BETA PARTICLES 1. Beta particles of at least 70 keV energy are required to penetrate the nominal protective layer of the skin. 2. The average energy of a beta-ray spectrum is approximately one-third the maximum energy. 3. The range of beta particles in air is ~12 ft (3.6 m) / MeV. 4. The range of beta particles (or electrons) in grams / cm 2 3 (thickness in cm multiplied by the density in g / cm ) is approximately half the maximum energy in MeV. This rule overestimates the range for low energies (0.5 MeV) and low atomic numbers, and underestimates for high energies and high atomic numbers. 5. The exposure rate in rads per hour in an infinite medium uniformly contaminated by a beta emitter is 2.12 EC / where E is the average beta energy per disintegration in 3 MeV, C is the concentration in ìCi / cm , and is the 3 density of the medium in grams/cm . The dose rate at the surface of the mass is one half the value given by this relation. In such a large mass, the relative beta and gamma dose rates are in the ratio of the average energies released per disintegration. 2 6. The surface dose rate through 7 mg / cm from a uniform 2 thin deposition of 1 Ci / cm is about 9 rads/h (90 mGy/h) for energies above about 0.6 MeV. Note that in a thin layer, the beta dose rate exceeds the gamma dose rate for equal energies released by ~100. Page 126 RULES OF THUMB FOR BETA PARTICLES 1. Beta particles of at least 70 keV energy are required to penetrate the nominal protective layer of the skin. 2. The average energy of a beta-ray spectrum is approximately one-third the maximum energy. 3. The range of beta particles in air is ~12 ft (3.6 m) / MeV. 4. The range of beta particles (or electrons) in grams / cm 2 3 (thickness in cm multiplied by the density in g / cm ) is approximately half the maximum energy in MeV. This rule overestimates the range for low energies (0.5 MeV) and low atomic numbers, and underestimates for high energies and high atomic numbers. 5. The exposure rate in rads per hour in an infinite medium uniformly contaminated by a beta emitter is 2.12 EC / where E is the average beta energy per disintegration in 3 MeV, C is the concentration in ìCi / cm , and is the density 3 of the medium in grams/cm . The dose rate at the surface of the mass is one half the value given by this relation. In such a large mass, the relative beta and gamma dose rates are in the ratio of the average energies released per disintegration. 2 6. The surface dose rate through 7 mg / cm from a uniform 2 thin deposition of 1 Ci / cm is about 9 rads/h (90 mGy/h) for energies above about 0.6 MeV. Note that in a thin layer, the beta dose rate exceeds the gamma dose rate for equal energies released by ~100. Page 126 RULES OF THUMB FOR BETA PARTICLES 1. Beta particles of at least 70 keV energy are required to penetrate the nominal protective layer of the skin. 2. The average energy of a beta-ray spectrum is approximately one-third the maximum energy. 3. The range of beta particles in air is ~12 ft (3.6 m) / MeV. 4. The range of beta particles (or electrons) in grams / cm 2 3 (thickness in cm multiplied by the density in g / cm ) is approximately half the maximum energy in MeV. This rule overestimates the range for low energies (0.5 MeV) and low atomic numbers, and underestimates for high energies and high atomic numbers. 5. The exposure rate in rads per hour in an infinite medium uniformly contaminated by a beta emitter is 2.12 EC / where E is the average beta energy per disintegration in 3 MeV, C is the concentration in ìCi / cm , and is the 3 density of the medium in grams/cm . The dose rate at the surface of the mass is one half the value given by this relation. In such a large mass, the relative beta and gamma dose rates are in the ratio of the average energies released per disintegration. 2 6. The surface dose rate through 7 mg / cm from a uniform 2 thin deposition of 1 Ci / cm is about 9 rads/h (90 mGy/h) for energies above about 0.6 MeV. Note that in a thin layer, the beta dose rate exceeds the gamma dose rate for equal energies released by ~100. Page 126 RULES OF THUMB FOR BETA PARTICLES 1. Beta particles of at least 70 keV energy are required to penetrate the nominal protective layer of the skin. 2. The average energy of a beta-ray spectrum is approximately one-third the maximum energy. 3. The range of beta particles in air is ~12 ft (3.6 m) / MeV. 4. The range of beta particles (or electrons) in grams / cm 2 3 (thickness in cm multiplied by the density in g / cm ) is approximately half the maximum energy in MeV. This rule overestimates the range for low energies (0.5 MeV) and low atomic numbers, and underestimates for high energies and high atomic numbers. 5. The exposure rate in rads per hour in an infinite medium uniformly contaminated by a beta emitter is 2.12 EC / where E is the average beta energy per disintegration in 3 MeV, C is the concentration in ìCi / cm , and is the density 3 of the medium in grams/cm . The dose rate at the surface of the mass is one half the value given by this relation. In such a large mass, the relative beta and gamma dose rates are in the ratio of the average energies released per disintegration. 2 6. The surface dose rate through 7 mg / cm from a uniform 2 thin deposition of 1 Ci / cm is about 9 rads/h (90 mGy/h) for energies above about 0.6 MeV. Note that in a thin layer, the beta dose rate exceeds the gamma dose rate for equal energies released by ~100. Page 126
Page 1 and 2:
HANDBOOK OF RADIATION DATA HANDBOOK
Page 3 and 4:
Abbreviations 115 Activity vs Expos
Page 5 and 6:
EMERGENCY RESPONSE SWIMS for Radiol
Page 7 and 8:
Major Injuries Occurring in Hazardo
Page 9 and 10:
ACUTE RADIATION EFFECTS ACUTE RADIA
Page 11 and 12:
CONTAMINATED / INJURED PERSON FORM
Page 13 and 14:
Z Density Z Density 76 Osmium Os 22
Page 15 and 16:
Radioactive Decay Radioactive Decay
Page 17 and 18:
Progeny kev and % abundance 41 Ar 4
Page 19 and 20:
Progeny kev and % abundance 65 Ni 6
Page 21 and 22:
Progeny kev and % abundance 134 I 1
Page 23 and 24:
Progeny kev and % abundance 220 216
Page 25 and 26:
Progeny kev and % abundance 234 Th
Page 27 and 28:
Thorium-232 Decay Chain including t
Page 29 and 30:
Uranium-238 Decay (including Radon
Page 31 and 32:
Progeny kev and % abundance Progeny
Page 33 and 34:
Progeny kev and % abundance 225 Ra
Page 35 and 36:
Progeny kev and % abundance Progeny
Page 37 and 38:
Rem/hr / Ci Sv/hr / GBq Half-Life C
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Gamma exposure at 30 cm vs Particle
Page 49 and 50:
Activity in DPM vs Particle Size in
Page 51 and 52:
DOSIMETRY 1 Bq = 1 dps = 2.7 E-11 C
Page 53 and 54:
INTERNAL DOSIMETRY Effective Half-L
Page 55 and 56:
1 RADIATION WEIGHTING FACTORS (ICRP
Page 57 and 58:
RADIATION INTERACTIONS Charged Part
Page 59 and 60:
CALCULATING NEUTRON SHIELD THICKNES
Page 61 and 62:
Neutron and Gamma Shielding SIMPLIF
Page 63 and 64:
Shallow Dose Correction Factor In a
Page 65 and 66:
Photon Fluence Rate ö from a Point
Page 67 and 68:
A comparison of signal levels for v
Page 69 and 70:
INSTRUMENT SELECTION AND USE Exposu
Page 71 and 72:
Airborne Radioactivity (long-lived)
Page 73 and 74:
AIR MONITORING Concentration Concen
Page 75 and 76:
Filter Media Characteristics for Al
Page 77 and 78: 10CFR20 DAC 10CFR835 DAC 10CFR20 AL
Page 105 and 106: STCs = Special Tritium Compounds 1
Page 107 and 108: Z # K K L L 96 Cm 109.10 123.24 14.
Page 109 and 110: Z # K K L L 45 Rh 20.21 22.72 2.70
Page 111 and 112: MDA when background and sample coun
Page 113 and 114: ELEVATIONS OF MAJOR AIRPORTS AND FA
Page 115 and 116: INTERNATIONAL AIRPORT ELEVATIONS (F
Page 117 and 118: SI and US “Traditional” Units A
Page 119 and 120: CONVERSION OF UNITS Length 1 angstr
Page 121 and 122: Radiological 1 rad = 100 ergs / g 1
Page 123 and 124: Power 1 joule/sec = 1E7 ergs/sec 1
Page 125 and 126: SURFACE AREA AND VOLUME CALCULATION
Page 127: RULES OF THUMB FOR ALPHA PARTICLES
Page 131 and 132: RULES OF THUMB FOR GAMMA RADIATION
Page 133 and 134: APPROXIMATE NEUTRON ENERGIES cold n
Page 135 and 136: Energy & Yield of neutrons from the
Page 137 and 138: Isotopic Mix of WG Pu 238 Pu 239 Pu
Page 139 and 140: Neutron exposure rate from the oxid
Page 141 and 142: Isotopic Mix of 20% Enriched U 238
Page 143 and 144: UNITS AND TERMINOLOGY “Special Un
Page 145 and 146: RADON FACTS 1 working level = 222 3
Page 147 and 148: Relative Risk Your overall risk of
Page 149 and 150: Advanced Radiation Instrumentation
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