Chemical Symbol:

Atomic Number:

Atomic Mass:

Proton Charge:

Proton Mass:

Neutron Charge:

Neutron Mass:

Electron Charge:

Electron Mass:

Isotopes are same number of

different number of

Radioactivity is when a nucleus becomes

due to too many

Radioactive Decay is the process in which a

atom becomes stable by emitting an

or

particle and/or

Radioactive Half Life is the amount of

that a quantity of radioactive material requires to decay to

of its original amount.

Characteristics: Highly energetic particle consisting of 2

and 2

emitted from the

Mass =

AMU.

charged.

ionizing.

Penetrating Power

penetrating.

Organ of interest

Means of production: Radioactive decay of uranium and activation products from defective or

fuel.

Source Geometry: Alpha particles travel only a few

in air.

Present around

or

systems when a fuel failure has occurred.

Characteristics: A high speed

Emitted from the nucleus. Mass =

amu. Negatively charged.

penetrating, but more than

Stopped by plastic or glass ~ 1cm thick.

Organs of interest:

Means of Production: Radioactive

of

products and/or

products. Source Geometry:

or

systems. Beta dose rate

very rapidly as you approach the sources.

Characteristics: Energetic form of electromagnetic energy. No

or

charge.

penetrating. Each

emits a specific energy gamma photon.

Penetrating Power: Travels

distances in air.

penetrating.

by dense materials like lead. Organ of interest:

Means of production:

- when a neutron is captured by a nucleus of an atom, a gamma ray is emitted.

- occurs at point of fission.

- when fission and activation products decay. Source Geometry:

source - hot particle.

source - pipe.

source - reactor face.

- defuelled channel.

cloud.

Characteristics: Mass of

amu. Normally located in the

electrical charge. Neutron radiation is the only type of radiation that can cause other materials to become

Penetrating Power:

penetrating. Shielded with

materials. Organs of interest:

Means of Production:

Neutrons - Fissioning of fuel in the reactor.

Neutrons - Gamma energies (photons) grater than 2.2 MeV interact with

in heavy water to produce photoneutrons. Source Geometry: Neutron

Characteristics: A radioactive isotope of

with a radiological T 1/2 of

years.

energy

emitter. An

hazard only. Decays to Helium-3. Exposure Pathways

Organs of interest: Whole body. Effective half-life of

to remove 1/2 of the tritium from your body through biological elimination. Means of Production:

activation of Deuterium Oxide (D2O).

Characteristics: Fine particulates of

material suspended in

They can be

or

lived. Exposure Pathways:

Organ of interest: Dependant on

Means of Production:

process and the

process.

Characteristics: Noble gases are

gases,

hazard. Exist as a

with uniform dose rate within the cloud. Decay to short lived airborne particulate. Exposure Pathways:

Organ of interest:

Means of Production:

process and

process (Ar-41).

Characteristics: Radioactive isotope of carbon.

energy

emitter. Radiological half-life of

years. Two forms:

and

Exposure Pathways:

Organ of interest:

- Whole body.

- Lungs. Means of Production:

Activation of Oxygen and Carbon by air ingress into systems.

Activation by Nitrogen ingress into systems.

Characteristics:

or

products that are distributed on a surface. Fixed Contamination is

to remove. Loose Contamination is

removed.

Particle are discrete radioactive particles approx

in size and >

mrem/h contact. Exposure Pathways:

if becomes airborne. Organ of interest: Fixed Contamination;

to the whole body,

to skin, eyes and extremities. Loose contamination; Dependant on solubility. Hot Particles;

Means of Production:

on the system.

of system components (valves, etc). Machining/Grinding of radioactive materials. Planting out on inner surfaces of

setting out on surface. Decay of

Characteristics:

contaminated with

or

products.

Liquids. Exposure Pathways:

hazard dependant on dose rates.

if an uptake occurs. Organs of interest: Dependant on radionuclide's in liquid. Means of Production: Mechanical

of equipment

of reactor system components.

of nuclear systems. Handling of contaminated liquids, e.g. D2O drums.

of equipment from irradiated fuel facilities. The handling of liquid sources (normally in laboratories).

slurries. Opening

ventilation systems.