Airborne Radioactivity Flashcards
Pathways for airborne dose
- External (submersion)
- Inhalation
- Ingestion
Submersion dose is limited for what?
Inert gases (noble gases)
3 noble gases
argon
krypton
xenon
Submersion dose risk b/c not absorbable
Hazard from a toxicant
- inherent toxicity
2. probability of reaching target site
components of airborne contaminants
Gaseous
Particulate
Difference between Gaseous and Particulate contaminants
Gases do not settle, particles do settle
Particle kinetics at < 0.1 Micron
thermodynamic properties
Particle kinetics 0.1 - 1.0 micron
thermodynamic and aerodynamic properties
Particle kinetics > 1.0 micron
aerodynamic properties
Thermodynamic properties of particle kinetics
Behaves like a gas - driven by diffusion
Aerodynamic properties of particle
behaves like a particle - driven by gravity and air resistance
MMAD
mass median aerodynamic diameter
terminal velocity
velocity where retarding forces equal gravitational forces
effect on dispersion from terminal velocity
low terminal velocity leads to more dispersion
3 methods of lung clearance
- cilia
- capillary absorption
- macrophage phagocytosis
Geometric LL CI
m / sigma^2
Geometric UL CI
m x sigma^2
Arithmetic LL CI
m - (2 x sigma)
Arithmetic UL CI
m + (2 x sigma)
ICRP 30 clearance regions
Nasopharyngeal
Tracheobronchial
Pulmonary
Pulmonary clearance methods
phagocytosis
cilia/coughing
capillaries
lymph drainage
NALI
0.5 Sv
SALI
0.05 Sv
DAC
Derived air concentration
amount in air that if inhaled will lead to the ALI if breathed for a year
