Radioactive Particles

Question 1

What does “Radioactive” refer to?

Answer 1

Refers to an element being unstable due to excess energy and in the process of trying to become stable, emits energy or is said to decry.

Question 2

When will radioactive decay stop?

Answer 2

Decay will continue until a non-radioactive, stable atom occurs.

Question 3

Properties of a Alpha Particle (ą)

Answer 3

The biggest and heaviest of radiation particles.
Composed of 2 protons and 2 neutrons.
Most damaging to humans when ingested.
2-5cm air and paper will shield Alpha

Question 4

Beta (B) particle properties

Answer 4

Very light particle with high velocity.
Nuclear origin with a
Easily deflected and scattered as it passes through matter
Can be absorbed by a few millimetres of aluminum and will travel hundred centimetres in are for losing energy 4-5m

Question 5

Neutron Radiation (N) properties

Answer 5

Has the same mass as a proton but has no electrical charge.
Very penetrating.
This type of radiation is not normally emitted during the natural decay process.
Most efficient material is water. Or any hydrogenous material, not lead

Question 6

Gamma Rays (ý)

Answer 6

This is electromagnetic energy with high energy levels.
They can travel up to 100 metres in air or further.
Highly penetrating and ionizing.

Gamma Rays are the most potentially hazardous.

Question 7

Industrial Isotopes in NDT

Answer 7

Radioactive material (radioisotopes) used for NDT proposes are called:
Iridium 192 (Ir192)
Cobalt 59 (Co59)
Both stable elements and exits in nature. When places in a reactor, they capture a neutron and start the radioactive decay process, giving off usual gamma rays

Specialized elements such as Cesium 137 (Cs137) and Yetterbium (Yb169) are also used.