For the

1
Nuclear Science Merit Badge Workshop

• For the
• Boy Scouts of America
• by
• The Pennsylvania State University,
• American Nuclear Society Student Section
• Spring 2005

2
Welcome

• The Radiation Science and Engineering Center
• at Penn State

Graphic by Vaughn Whisker
Breazeale Nuclear Reactor
3
Basic Safety Rules

• No food, drinks or gum outside of designated
  areas
• No cell phones or pagers
• No cameras
• If you need to leave the group for any reason
  first ask an ANS member to escort you.
• Each group will have at least one member assigned
  to wear a dosimeter.
• A dosimeter is a small device to measure
  radiation exposure.
• If you read the dosimeter now it will read zero.
  At the end of the day it should also read zero
  because we are not going to take you anywhere we
  expect there to be significant radiation exposure.

4
Lets Get Started

Requirement 1
ALARA Alpha Particle Atom Background
Beta Particle Contamination Curie (Ci) Becquerel (Bq)
Gamma Ray Half-life Ionization Quark
Isotope Neutron Nuclear Energy Nuclear Reactor
Particle Accelerator Rad Gray (Gy) Radiation
Radioactivity Radon (Rn) Rem Sievert (Sv)
X-Ray
5
ALARA

• As Low As Reasonably Achievable
• This is the principle by which the nuclear
  industry operates. The goal is to minimize the
  radiation exposure of workers.

ALARA TIME DISTANCE SHIELDING
6
Alpha Particle

• (alpha ray, alpha radiation) An electrically
  charged particle made of two protons and two
  neutrons. These are thrown off by many
  radioactive materials, including uranium and
  radium. An alpha particle is identical to the
  nucleus of a helium atom.
• Symbol ?

7
Atom

• The smallest piece of an element. They are made
  up of protons, neutrons, and electrons and the
  number of protons determines the kind.

8
Background Radiation

• The ionizing radiation always present in nature
  from cosmic rays or from radioactive materials in
  the air, water, food, ground, building materials,
  and some consumer products.

9
Beta Particle

• (beta ray, beta radiation) An electrically
  charged particle thrown off by many radioactive
  materials. If is a free moving electron and
  possesses the smallest negative charge found in
  nature. Beta particles come out of radioactive
  atoms at high speeds.
• Symbol ß

10
Contamination

• Radioactive material deposited or dispersed in
  materials or places where it is not wanted.

11
Curie (Ci)

• A measure of the rate at which radioactive
  material throws off particles or radiation. It is
  named in honor of the French chemists, Marie and
  Pierre Curie. One curie is equal to the activity
  in one gram of radium.

12
Becquerel (Bq)

• The SI (metric) unit of radioactivity in a
  material. One Bq measures one disintegration per
  second.

13
Gamma Rays

• (gamma radiation) A form of ionizing radiation
  energy (the same as X-rays) given off when the
  nucleus of some radioactive materials
  disintegrate.
• Symbol ?

14
Half-life

• The amount of time it takes for one half of a
  group of radioactive atoms to decay.
• Symbol (t1/2)

15
Ionization

• A process by which atoms lose one or more
  electrons and are left with a positive electrical
  charge. Some atoms gain an electron and are
  negatively charged.
• Radiation hitting clouds (or groups) of atoms
  changes some of them into ions, some positive and
  some negative.

16
Quark

• A sub-nuclear, fundamental particle of matter
  that makes up protons and neutrons.

quark Flavor Mass (GeV/e2) Electric charge(e)
u up 0.004 2/3
d down 0.008 -1/3
c Charm 1.5 2/3
s Strange 0.15 -1/3
t top 176 2/3
b bottom 4.7 -1/3
17
Isotope

• Atoms of the same chemical element having the
  same number of protons (the same atomic number)
  but with a different number of neutrons
  (different atomic weights). Some isotopes are
  radioactive (radioisotopes) and some are not
  (stable).

18
Neutron

• A basic atomic particle, having no electrical
  charge, found in the nucleus of atoms. It has an
  atomic weight of one.

19
Nuclear Energy

• Energy released when the nucleus of an atom
  splits (fission), joins with another nucleus
  (fusion), or disintegrates (radiation). Nuclear
  energy is the most exact terms to describe the
  energy produced in a nuclear reactor.

20
Nuclear Reactor

• A device in which a nuclear fission chain
  reaction takes place.

21
Particle Accelerator

• An electric device for speeding up electrically
  charged particles such as electrons and protons.
  These are then used for smashing into atoms at
  high speeds. This allows scientists to study the
  particles and forces that make up atoms.

22
RAD

• A unit of measure of how much radiation energy
  something absorbs when exposed to a radiation
  source.

23
Gray (Gy)

• The SI (metric) equivalent of a rad. One gray is
  equal to 100 rads.

24
Radiation

• The energetic particles or rays thrown out by
  radioactive elements or produced by X-ray
  machines. The best term for atomic radiation is
  ionizing radiation, because sound waves, light
  waves, and radio waves are also kinds of
  radiation.

25
Radioactivity

• The throwing out of charged particles or gamma
  rays from the nucleus of the atom. Some elements
  are naturally radioactive, while others can be
  made radioactive by squeezing extra neutrons into
  the nucleus.

26
Radon (Rn)

• A heavy radioactive gas given off by rocks
  containing radium (or thorium). Rn-222 is the
  main isotope.

27
Rem

• A unit describing the intensity of radiation, the
  type of radiation, and the effect on the body.

28
Sievert (Sv)

• The SI equivalent of the rem. One sievert is
  equal to 100 rem.

29
X-ray

• Radiation produced inside a vacuum tube when
  high-speed electrons hit a metal target. When
  these rays pass through an object, they give a
  shadow picture of the denser portions. They must
  be used carefully because of their ability to
  ionize atoms in the body.

30
We Covered

Requirement 1
ALARA Alpha Particle Atom Background
Beta Particle Contamination Curie (Ci) Becquerel (Bq)
Gamma Ray Half-life Ionization Quark
Isotope Neutron Nuclear Energy Nuclear Reactor
Particle Accelerator Rad Gray (Gy) Radiation
Radioactivity Radon (Rn) Rem Sievert (Sv)
X-Ray