Alpha Particles

Page
3

only applies in air

only applies to energies less than 3 MeV

Named after Wilhelm C. Roentgen

(thus the abbr . is capital “R”)

Slide 25

rad

Slide 26

rad

1 rad = 1 Roentgen

Slide 27

rem

Slide 28

rem

The unit of dose equivalent for any type of ionizing radiation absorbed by body tissue in terms of estimated biological effect - Unit of dose equivalent

Dose in health record is in units of rem

1 rem = 1 Roentgen

Roentgen Equivalent Man

Slide 29

Quality Factor (Q)

The specific value that accounts for the ability of different types of ionizing radiation to cause varying degrees of biological damage

X-rays, gamma rays, & beta particles 1

Neutrons & High energy protons 10

Alpha Particles 20

Slide 30

Curie (Ci)

Radiation hazard does not solely depend on the activity. It also depends on the type of decay (alpha, beta, photon, etc.)

Named in honor of Pierre Curie

Slide 31

SI Radiation Protection Units

Becquerel (Bq) for Curie

1 Ci = 3.7 x 1010 Bq

Gray (Gy) for rad

1 Gy = 100 rad

Sievert (Sv) for rem

1 Sv = 100 rem

Slide 32

Unit Analysis

BASE UNIT CONVERSION TABLE

Unit Unit Conversion

1 Bq 2.7 x 10-11 Ci

1 Ci 3.7 x 1010 Bq 1 Bq 1 dis/sec

1 dis/sec 2.7 x 10-11 Ci

1 Ci 3.7 x 1010 dis/sec

Slide 33

Unit Analysis (Con’t.)

BASE UNIT CONVERSION TABLE

Unit Unit Conversion

1 rem 0.01 Sv

1 Sv 100 rem

1 rad 0.01 Gy

1 Gy 100 rad

1 R 2.58 x 10-4 C/kg

1 meter 3.28 ft (39.37in)

Slide 34

Summary

Radiation Protection unit definitions (including SI units)

Unit Prefixes

Unit conversions

Slide 35

Old Terms

Roentgen-Based on the quantity of electrical charges produced in air by X or Gamma photons 1R=2 billion pr

RAD-Radiation Absorbed Dose is the work energy resulting from the absorption of one ROENTGEN or 6.24 E5 Mev

Slide 36