1. Radiation Safety Capt. David Ayre CAP, SWR-TX-176

2. RADIATION
The definition of radiation is the emission (sending out) of waves and/or particles thru space.
In the dictionary radiation is defined as “sending out in rays” such as light or heat.
“All types of radiation can cause damage to tissue such as burns. Everybody is familiar with sunburn or a burn associated with fire. A burn is simply energy deposited in an area. Some types of radiation cause more damage to issue for the relative amount of energy deposited.
This is because some types of radiation have the ability to interact with atoms causing the atoms to give up electrons creating ions. It is these active ions which can cause cell damage.
Ionizing radiation is more harmful than non- ionizing.
Ionizing radiation will penetrate the skin and affect the body. non-ionizing radiation only affects the surface.

3. IONIZING OR NON - IONIZING TYPES OF RADIATION TYPES OF RADIATION
heat
light
radio waves
x-rays
nuclear
Radiation can be classified into two different categories ionizing and non-ionizing.
Ionizing radiation has the ability to knock off ELECTRONS and these charged particles are called IONS.

4. Nuclear Radiation
For the purpose of this course we will use the term radiation to refer only to NUCLEAR RADIATION.
Nuclear Radiation causes harm by entering the body and depositing some or all of it’s energy.
Since nuclear radiation is ionizing radiation electrons are knocked off creating ions that react with the body tissue.
Energy that has the ability to ionize causes more damage that the same amount of non-ionizing energy such as light.
One source of radiation is the nuclei of an unstable atom. These radioactive atoms become more stable when the nuclei ejects or emits subatomic particles and/or high-energy photons (gamma rays).

5. This Is the Way the Atom Probably Looks
Atomic Structure
Electron
Proton
Nucleus
Neutron

6. Atomic Number Atomic number (Z number)
is the number of PROTONS in the nucleus of an atom.
The atomic number is defined as the number of protons in an atom.
The atomic number determines what element the atom is. For example, the atomic number of oxygen is 8 all atoms with eight protons are oxygen.

7. Atomic Mass Atomic Mass (A number), is the number of PROTONS plus
the number of NEUTRONS in the nucleus of an atom.
The atomic mass is defined as the number of neutrons plus the number of protons in an atom.
In the case of Oxygen the atomic mass is usually 16. The typical oxygen atom contain eight protons and eight neutrons.

8. Mass and Charges of Basic Atomic Particles
Proton
1 amu
+ 1
Neutron
0 or neutral
Electron
1/2000 amu
- 1
Protons have a mass of 1 atomic mass unit or AMU, they have a charge of plus one and are found in the nucleus of the atom.
Neutrons are neutral particles with a mass of 1 AMU and act to hold the nucleus together.
Electrons have a mass of 1/2000 AMU and a charge of minus 1.

9. Atoms with the same atomic number, but different atomic mass.
ISOTOPE
Atoms with the same atomic number,
but different atomic mass.
Carbon-14
(6P + 8N)
Atomic Mass = 14
Carbon-12
(6P + 6N)
Atomic Mass = 12
Carbon-13
(6P + 7N)
Atomic Mass = 13
6 Protons
6 Neutrons
7 Neutrons
8 Neutrons
Atoms with the same atomic number but different atomic mass are called isotopes. Isotopes of an atom react chemically the same however their mass is different.

10. IODINE ISOTOPE EXAMPLE
Atomic Mass
Atomic Number
Number of Neutrons
I 123
123 53 70
I 125
125 72
I 131
131 78
Iodine 123 is sable form of Iodine.
Iodine 125 is radioactive and is use in the medical profession.
Iodine 131 is also radioactive and is the most common type of radioactive tracer material used in the oil field.

11. Discovery of Radiation
Henri Becquerel 1896
Ernest Rutherford
The type of ionizing radiation which was first discovered was the X-ray. In 1895 Roentgen discovered something that would pass through glass and cause a zinc sulfide screen to become florescent. He didn’t know what to call these “things” so he called these “rays” X-rays for the Unknown.
Then in 1896 Becquerel discovered that some type of radiation from certain materials could fog photographic film. Studies revealed that this was Uranium.
Also discovered thorium.
The Curies found that certain materials would give off radiation in a amount proportional to the amount of material present.
They also discovered a pitch blend ore that gave off more radiation than uranium or thorium.
After more research they discovered a new element Radium.
Wilhelm Roentgen 1895
Marie Curie-To describe the behavior of uranium and thorium she invented the word “radioactivity” --based on the Latin word for ray.

12. RUTHERFORD’S EXPERIMENT
Photographic Plate
Using radium in a lead shield with a round opening Rutherford Noticed that a round circle would appear on a zinc sulfide screen. Placing a strong magnet near the source three round circles would appear on the screen.
Thus proving that there are at least three types of radiation coming from the source one positive, one negative and one neutral.
He named these Alpha, Beta, and Gamma Radiation.

13. Several Inches of Lead or Steel
TYPES OF RADIATION
Types of Radiation
Mass
Charge
Stopped By
Alpha 4
+ 2
Thin Sheet of Paper
Gamma Ray
No Mass
No Charge
Several Inches of Lead or Steel
X Ray
Beta
1/2000
- 1
Thin Aluminum
Neutron 1
High Hydrogen Content
An atom that undergoes spontaneous decay is called Unstable or radioactive.
Alpha Decay (an unstable isotope can under go several types of change or what is called decay. Basically there are three types of radiation given off by the decay of an atom. They are Alpha, Beta and Gamma.)
Alpha particles consists of two protons and 2 neutrons, has a charge of plus 2 and a mass of 4 AMU. These are relatively large can travel a few inches in air and can be stopped by a thin sheet of paper. When a alpha particle is given off the atoms the atoms atomic number decreases by 2 and atomic mass decreases by 4. For example when Radium 226 gives off an alpha particle it becomes Radon 222.
Many times a atom will be in an excited state and possess to much energy. The atom will sometimes give off this energy in the form of Gamma Rays. Gamma Rays are massless packets of pure energy with no charge. Can be stopped with thick lead or steel.
Beta particles are particles with the mass and charge of an electron that are emitted from the nucleus of an atom. This can be thought of as a neutron becoming a proton. When a beta particle is given off the atomic number increases by one and the atomic mass stays the same. Beta particles can travel several feet in air and can be stopped by a thin sheet of Aluminum. When Lead 214 gives off a beta particle it becomes Bismuth Some radioactive isotopes go through one decay to reach a stable state while others go through a chain of decays to reach a stable state. On the cover of your workbook is and drawing of Radium 226 decay.
NEUTRON REACTION - Often times a alpha particle can react with other atoms to produce neutrons. Neutrons can be stopped by materials that have high hydrogen content. For example in our Neutron Logging Sources Americium 241 gives off an Alpha particle and it reacts with the Beryllium Atoms to produce neutrons.

14. Electromagnetic Spectrum

15. INDUSTRIAL USES OF RADIOACTIVE MATERIALS
Power Plants
Medical
Farming
Ranching
Textile
Auto
Soda Can
Medical
Oil Well Logging
Military
Nuclear power plants
HAVE CLASS NAME A INDUSTRY THAT DOESN’T USE RADIATION!

16. CASES OF HIGH OCCUPATIONAL EXPOSURE TO RADIATION
Early Scientists
Watch Dial Painters
Nuclear Weapons Research
Military Personnel
Emergency/Medical Personnel
Several examples are:
Early scientists received large doses of radiation while performing experiments resulting in several cancer deaths.
The watch dial painters in the 1920’s would moisten there brushes with there tongue and consequently ingested large amounts of Radium resulting in a few hundred deaths from bone cancer.
Another case is during the later 1930’s there were deaths due to accidents with particle accelerators.
Also during the development of nuclear weapons during the 1940’s there were several deaths due to high exposure to radiation.
Also in the early 1950 large shoe stores had fluoroscopes in them.
Kids playing with them caused bone cancer to feet and ankles.
Fluoroscopes are a X - Ray machine.
Now all x - ray machines are licensed just like all radioactive materials.

17. COMMON PREFIXES Giga (G) = 1 billion Mega (M) = 1 million
kilo (k) = 1 thousand
milli (m) = 1 thousandth
micro (u) = 1 millionth
In the SI System of Measure different prefixes are used to denote multiplies of units or parts of units.
Mega = 1 million
Kilo = 1 thousand
milli = 1 thousandth
micro = 1 millionth
For example a kilogram is 1 thousand grams, while a milligram is one thousandth of a gram.

18. radioactive source and
UNITS OF MEASUREMENT
Curie
A UNIT used to measure
the activity of a
radioactive source and
equals
37,000,000,000
disintegration's per
second.
The SI UNIT is the
_____Becquerel____
which is one nuclear
transformation or
one disintegration
per second.
Definition of Curie We measure the activity of a source (or source strength) in Curies, millicuries, or microcuries.
One Curie is equal to 37 billion disintegration's per second. (This is the activity of one gram of Ra 226).

19. Roentgen A measure of the ionization effect Gamma and X radiation
UNITS OF MEASUREMENT
Roentgen
A measure of the
ionization effect
Gamma
and
X radiation
have in AIR.
A measure of the ionizing effect of radiation in air.
The amount of radiation that creates E 09 ion pairs in air.

20. Roentgen Equivalent Man
UNITS OF MEASUREMENT
REM
A measure of the
biological effect
radiation has on man.
stands for
Roentgen Equivalent Man
A measure of the biological effect of the absorbed radiation dose.
Millirems are commonly used.

21. Material after one Half-Life Material after two Half-Lives
The time required for the amount of radioactive material to decrease by one half.
Original Material
Material after one Half-Life
Material after two Half-Lives

22. HALF-LIVES OF VARIOUS ISOTOPES
Half-Life
Am 241
454 Years
Cs 137
30 Years
Ra 226
1602 Years
I 131
8 Days
Co 60
5.2 Years
The time required for 1/2 of the radioactive atoms to reach a stable state is called HALF-LIVE.
When a particular radioactive isotope will decay cannot be predicted.
However every radioactive isotope decays at a different rate.
Problem: On one June you have 10 millicuries of I - 131, assuming no use of material, how much I would you have on June 17? (I half-life is 8 days)

23. Detecting Radiation and the PHOTOGRAPHIC PROCESS
FILM BADGES
Radiation will expose film just as light will.
The greater the dose of radiation the darker the film will become.
Film badges are used in the medical profession a lot because usually only trying to measure only one type of radiation. ( X-RAY ).
As you know Becquerel discovered that radiation can expose film just as visible light can.
This photographic process is used in industrial radiography and medical X - rays, and in some personnel monitoring.
For personnel monitoring the badges must be changed monthly since the film can fade with age.
Some film badges have various filters to try to determine energy level of the radiation.
Film is also sensitive to developing errors.

24. THERMOLUMINESCENT DOSIMETER
TLD’s use three
chips that when
exposed to radiation
store the energy.
When the chip is
heated it gives off
light proportional to
the radiation
absorbed.
LANDAUER
John Doe N
JAN 01, Z1
COMMON TLD’S MEASURES BOTH GAMMA AND NEUTRON.
THE NEUTRON MONITORING PORTION OF THE BADGE CONSISTS OF TWO PIECES OF PLASTIC.
THE FIRST ONE IS SIMPLY A PIECE OF POLYETHYLENE TO SLOW THE NEUTRONS.
THE OTHER IS A SPECIALLY TREATED PLASTIC THAT, WHEN EXPOSED TO NEUTRONS LEAVE TRACKS ETCHED INTO THE PLASTIC.
TO PROCESS THE BADGE THE CHIP IS READ UNDER A MICROSCOPE AND THE TRACKS ARE COUNTED. T T

25. OPTICALLY STIMULATED LUMINESCENCE (OSL) DOSIMETER
OSL’s use two thin Al2O3 strips which when exposed to radiation record Photons (X & d Rays) in the 5 keV / 40 MeV range & Beta Particles in the 150 keV / 10 MeV range.
During analysis, the Al2O3 is stimulated with selected frequencies of laser light, which cause it to become luminescent in proportion to the amount of radiation exposure received.
A third component, for the measurement of Neutrons, is also enclosed. This is a Neutrak 144 Allyl Diglycol carbonate solid state track detector. In this case measurement is made by chemical etching followed by track counting. Energies measured are between 100 keV / 30 MeV.
JOHN
DOE
TRAINING
luxel
LANDAUER®
OSL MEASURES BOTH GAMMA AND NEUTRON.
THE NEUTRON MONITORING PORTION OF THE BADGE CONSISTS OF TWO PIECES OF PLASTIC.
THE FIRST ONE IS SIMPLY A PIECE OF POLYETHYLENE TO SLOW THE NEUTRONS.
THE OTHER IS A SPECIALLY TREATED PLASTIC THAT, WHEN EXPOSED TO NEUTRONS LEAVE TRACKS ETCHED INTO THE PLASTIC.
TO PROCESS THE BADGE THE CHIP IS READ UNDER A MICROSCOPE AND THE TRACKS ARE COUNTED.
FRONT

26. OPTICALLY STIMULATED LUMINESCENCE (OSL) DOSIMETER
Dose Measurement Range
Photon 1 mREM to 1000 REM
Beta Particle 10 mREM to 1000 REM
Neutron 20 mREM to 25 REM
Accuracy
Deep Dose = ±15% at the 95% confidence interval for photons above 20 keV
Shallow Dose = ±15% at the 95% confidence interval for photons above 20 keV and beta particles above 200 keV T
Whole Body (chest) A2
TLD’S USED BY HALLIBURTON MEASURES BOTH GAMMA AND NEUTRON.
THE NEUTRON MONITORING PORTION OF THE BADGE CONSISTS OF TWO PIECES OF PLASTIC.
THE FIRST ONE IS SIMPLY A PIECE OF POLYETHYLENE TO SLOW THE NEUTRONS.
THE OTHER IS A SPECIALLY TREATED PLASTIC THAT, WHEN EXPOSED TO NEUTRONS LEAVE TRACKS ETCHED INTO THE PLASTIC.
TO PROCESS THE BADGE THE CHIP IS READ UNDER A MICROSCOPE AND THE TRACKS ARE COUNTED.
BACK

27. OPTICALLY STIMULATED LUMINESCENCE (OSL) DOSIMETER
John
Doe
TRAINING
luxel
LANDAUER®
The OSL is the principle device
used to measure radiation
exposure personnel.
The OSL will only measure what
your body will receive and does not
“protect” from radiation.
A OSL will simply measure what
you have been exposed to and will
allow us to determine if you have
received to much radiation.

28. Radiation Quality is an indication of the type of radiation received
RADIATION MONITORING
Radiation Quality is an indication
of the type of radiation received
Radiation Quality Type of Radiation Received
P Gamma Only
CPN Combination Gamma and Neutron
NF Fast Neutron
M Minimal (Less than 1.0 mR)
If you lose your badge during the quarter you should immediately notify your supervisor so a replacement badge can be issued.
Exposure records must be retained for a period of thirty years after termination of employment.
Employees who leave the company may and should request there radiation exposure from the HSE department.
This request must be in writing and come from the emplyee not his new employer.
Whenever an employee transfers a new TLD service card should be completed and listing his new location and forwarded to the HSE Department. Then the employees TLD service will be transferred to his new location.
Up until Jan. 1, 1994 if a TLD was not returned the company used to add a maxium exposure of one quarter to your report. (1250mR).
Since then now a extensive investigation into your radiation exposure during the applicable quarter is done and a best guess exposure is added to your exposure records. Will look at TLD’s of the people working with you during the time the TLD was lost.
Show old Landauer Report.
You should intial the report after veiwing it.

29. MAXIMUM PERMISSIBLE EXPOSURES
5 REM per Year
Lifetime Dose – ( Age - 18 ) * 5 REM
Recommended exposure while pregnant
500 mREM
Average exposure for Wireline
Logging & Perforating Personnel
mREM per Quarter
The maximum permissible exposure permitted while pregnat is no different than any other employee according to the regulations. However the National Council on Radiation Protection Recommends that a pregnant employee receive a maximum occupational dose of radiation less than 500 millirems for the entire term of pregnancy.
The average exposures for L & P employees is low. The group with the highest exposure are open hole crews.
Their average is in the millirem/quarter range.
If your actual reading is greater than about 300 mR you may need to look at your procedures and see if there is anything that you can to reduce your exposure.
The average Halliburton exposure is lower than the industry average for well loggers.

30. Detecting Radiation and the ENCLOSED GAS VOLUME PROCESS
Electrical Current Measuring Device
Anode +
Cathode - + -
Voltage Source
Inert Gas
Incident Ionizing Radiation
Types of equipment that use an enclosed gas are GM probes (Geiger counter), ionization chambers, and proportional counters.
The survey meters Halliburton uses are both Enclosed Gas Volume process of detecting radiation.
Geiger-Mueller Counters
An enclosed tube has an anode and a cathode and usually an inert gas inside the tube. The radiation enters the tube ionizing the gas thus creating a current flow. The amount of radiation is proportional to the current flow.

31. Detecting Radiation and the SCINTILLATION CRYSTAL PROCESS
Optical Coupling
Grease
Scintillating Crystal
Preamp
High
Voltage
Dynodes
Photo-Cathode
Glass
Vacuum Tube
e- Electrons
P Photons
Gamma Ray
Photo-Multiplier
Tube
When radiation strikes a special crystal, light is emitted and the light is converted to electrical energy.
Approx. five times more sensitive than the GM probe.
Type of detection used in most Gamma Ray Tools.
Also used are liquid scintillation “cocktails” for detecting low level beta particles and leak testing.

32. Detecting Radiation and the Direct-Read Pocket Dosimeter
Milliroentgens 50
100
150
200
EYE
PIECE D
LENS C B + -
DIRECT - READING POCKET DOSIMETER
A. Charging Rod
B. Metal Support for Fibers
C. Movable Fine Metal Coated
Quartz Fiber
D. Transparent Scale
Another deceive used to measure exposure to radiation is the direct reading pocket dosimeter.
The pocket dosimeters that most L & P PSL districts have usually only measure Gamma and X-rays.
However also available are neutron and thermal neutron dosimeters.
Not really needed, because all of the tracers material Halliburton uses are Gamma emitters, so therefore have no need for neutron dosimeters.
Gives a direct reading of exposure by discharging a filament.
Dosimeter can be charged in the shop using a charger.
It recommended , but not required that a direct reading dosimeter be worn on tracer jobs or when unusual activities will cause you to receive potential high exposure. Such as performing leak tests.

33. VICTOREEN MODEL 493
The most commonly used survey maters are Ludlum model 2 or Victoreen 493.
Both measure radiation from 0 up to 50 mr/hr.
All must be calibrated in intervals not to exceed six months.
The the current calibration sticker must be attached to the meter.
The calibration is done by local personnel in the district if have own calibration source. Most now use outside vendors to perform the calibrations.
Remember to follow these steps when using a survey meter.
In addition to the multiple range witch positions a battery check position should be checked every time the meter is used.
Check for current calibration sticker.
Starting well back of the source switch to the most sensitive scale. The exposure rate would be the meter reading times the range setting.
Slowly approach the item being surveyed while monitoring the meter.
If the meter reaches full scale switch to the next higher scale.
You may use the reset button ( if available ) to re - zero the meter to eliminate the time delay in taking a reading.
Make and record the required reading and record the meter serial number used for surveying.

34. Ludlum Model 2
The exposure rate would be the meter reading times the range setting
Always go to battery check position to insure the batteries are good.
HV Switch You can use the reset button to re-zero the meter to eliminate the time delay in taking a reading.
Audio Switch Off and On This meter has a audio which can be used to give a warning to people in the area.
It is a good practice to use a meter with audio while calibrating tools to give a warning to people in the area.
Switch F and S Is available to slow the response to eliminate some of the statistical response.

35. What exposure rate is this meter reading?
X 1 _______mREM/hour
X 10 _______mREM/hour
X 100_______mREM/hour
X ______mREM/hour
X ______mREM/hour
X ______mREM/hour
The exposure rate would be the meter reading times the range setting
The Victoreen 493 reads
.25 mR/h
2.5 mR/h
25.0 mR/h
The Ludlum model 2 reads

36. OCCUPATIONAL DOSE RATES
_____ mREM/hour
100 mREM/year
(General Public)
500 mREM/year
(If Attended Awareness Training)
5 REM/year
The second chapter is mainly concerned with heath effects of radiation exposure.
First lets look at the occupational dose rate, or the amount of radiation we can receive working with radiation.
This also will give us something to compare background exposure we receive from living on the planet earth.

37. BACKGROUND RADIATION DOSE
Source
Radiation Received
Radon Gas
200 mREM/year
Daughter Products
28 mREM/year
Food & Water
40 mREM/year
Cosmic Rays
Medical Radiation
53 mREM/year
T.V. Consumer Products
7 mREM/year
TOTAL 356 mREM/year
All people are continuously exposed to ionizing radiation from natural background sources.
Gamma and X-rays from outer space.
Radioactive isotopes are present in the soil and sometimes find their way in the food chain.
Also, radon from the decay of radium, exposes us to background radiation.
From background sources the average individual receives the following amounts of radiation.
This total represents an average exposure for all people.
The medical is the total medical exposure divided by the total number of people in the US.
The cosmic exposure will increase depending on altitude and latitude.
For example you would receive more radiation for cosmic rays in Denver than you would in Miami.
This figure is a higher than previously thought due to the addition of the Radon Hazard.

38. RADIATION DOSES FROM OTHER SOURCES
SOURCE EXPOSURE
One Hour of Jet Flight at 37,000 Feet mREM/hour
Chest X-Ray or Dental Exam mREM/hour
Dose to Unborn Child Due to Background mREM/hour
Pelvic Exam mREM/hour
Lower GI Series mREM/hour
Areas of High Background Up to 5000 mREM/year
From other sources you would receive the following potential exposures:
The areas of high background are several areas in the world where there are high concentrations of naturally occurring radioactive materials in the soil certain areas in Brazil and India are such areas.

39. Biological Effects Due to Exposure Can Be Divided Into Two Groups
EARLY EFFECTS LATE EFFECTS
(ACUTE) (DELAYED)
Blood Count Changes Genetic Damage
Vomiting Increased Cancer Risk
Nausea Shortened Life Span
Death
Unfortunately there is not much known about the effects of long term exposure to low levels of radiation.
Most of the studies use survivors of the atomic weapons blasts in Japan and then extrapolate the data back to the low level exposure.
Biological effects due to exposure can be divided into two groups, early or acute and late or delayed.
Early Effects
Early effects are effects that can be observed within several weeks of the initial exposure. They include changes in blood counts, vomiting, nausea, and possibly even death. These effects usually observed in case of high exposure in a relatively short period of time. Usually at levels greater than 30 REMS in less than one week.
Late Effects
Late or delayed effects are not observed often times for years after the exposure. This includes an increase in the rate of cancers, shortened life span, and genetic defects. The difficulty come in determining whether these are radiation effects or effects due to other sources. Example, if a person develops leukemia it is impossible to determine if this was caused by radiation exposure or a different cause. Another problem is that industrial exposure to radiation is a relatively new health risk and there hasn’t been enough of time lapse to allow all the data to be collected.

40. Some Acute Effects of High Exposure Over a Short Period Are
DOSE (1 week) EFFECT (30 days)
REM Detectable changes in blood counts
REM Nausea and vomiting within 24 hours
REM Death may occur
350 REM % will Die within 30 days
REM Death will probably occur
over 600 REM % will die within 30 days
Give example that up to 30 REMs medical science can not measure a effect on the human body.
Give example of 50% rule. Which one dies depends on the physiological make up of both people at the time of exposure. If one person had a cold he would be the one who dies.
The average exposure for fireman fighting the nuclear power plant that blew up in Russia was 1650 REMS to whole body. Where all ready dead and didn’t know it.

41. Estimated Loss of Life Expectancy From Health Risks
HEALTH ESTIMATES OF DAYS OF
RISK LIFE EXPECTANCY
LOST, AVERAGE
Smoking (6.5 years)
Cigarettes/Day
OVERWEIGHT (1.2 years)
(by 20 %)
The effect of low level exposure to radiation can be compared to other everyday risks we all take and accept, these risks can include driving a car, smoking, drinking and accidents at the home.
When comparing these risks the average number of days shortened from your life span is often used.
Here is a chart comparing various conditions.
Occupational exposure to radiation shortens the average life span by 40 days.
This is less than consuming alcohol, car accidents.
Some conditions can actually increase your life expectancy such as air bags or the use of a smoke detector.

42. RISK CHART CONTINUED AUTO ACCIDENTS 200 DAYS ALCOHOL CONSUMPTION
Auto Accidents 200 day reduction in life expectancy.
This is the biggest risk all of us face each day.
Alcohol Consumption
130 days reduction in life span.

43. RISK CHART CONTINUED HOME ACCIDENTS 95 DAYS DROWNINGS’ 41 DAYS

44. RADIATION (Calculated)
RISK CHART CONTINUED
SAFEST JOBS
(SUCH AS ………………..)
30 DAYS
NATURAL
BACKGROUND
RADIATION (Calculated)
8 DAYS
Even the safest jobs like teaching has a risk with it! The risk of teaching is a 30 day reduction in life span.
By living on the planet earth you have the risk of 8 day reduction in life span from natural background radiation.

45. RISK CHART CONTINUED 1 REM Occupational Radiation Dose
Calculated (Industry Average Is 0.34 REM/year)
1 DAY
1 REM/year for 30 Years, Calculated
30 DAYS
5 REM/year for 30 years, Calculated
150 DAYS
These estimates indicate that the health risk from occupational radiation exposure are not greater than risk associated with many other events or activities we encounter in normal day-to-day activities.
SHOW OTHER RISK CHART ABOUT WORKING IN A HIGH-RISK OCCUPATIONS IF WANT TO.

46. Everyday Items Containing Radioactive Materials
Scale Found on Oil Field Pipe
Brazil Nuts
Smoke Detectors
Lantern Mantles
Some Ceramics
Salt Substitutes
Certain everyday items contain radioactive materials.
Smoke Detectors
Lantern Mantles (Use Survey Meter in class and put a lantern mantle on probe to with audio on so class can he the different from background and lantern mantle.)
Some Ceramics
Salt Substitutes
Brazil Nuts
Some scale found on oil field pipe.

47. AS LOW AS REASONABLY ACHIEVABLE
ALARA PRINCIPLE
ALARA
stands for
AS LOW AS REASONABLY ACHIEVABLE
Alara stands for as low as reasonable achievable.
Halliburton subscribes to this ALARA principle.
It means that employers are committed to maintain radiation exposure for its employees as low as achievable even if they are currently well below the maximum permissible exposures.
Part of the ALARA principle states that we should receive no exposure if we gain no benefit from that exposure.

48. REDUCING YOUR EXPOSURE
The three most important safety rules to remember while working with radiation are
Time
Distance
Shielding
While most Halliburton exposures are well below limits set by the NRC or the state you still need to keep exposure as low as possible since there is still relatively little known about the long term effects of low level exposure to radiation.
There are three different concepts you should utilize to reduce your exposure to radiation.
This is probably the three most important concepts in Radiation Safety.
The three concepts are Time, Distance, and Shielding.

49. The Effect of Time on Radiation Exposure
EXPOSURE = DOSE RATE X TIME
For Example: 495 mREM per hour
1 HOUR = 495 mREM
2 HOURS = 990 mREM
3 HOURS = 1485 mREM

50. The Effect of Distance on Radiation Exposure
The Equation for Calculating
Radiation Exposure as a
Function of Distance:
I 1 x ( D1 ) 2 = I 2 x ( D 2 ) 2 OR
I 2 = I 1 x ( D 1 ) 2
( D 2 ) 2
I1 x (D1)2 = I2 x (D2)2
Example
I1 = Intensity at point one equals 100 mR per hour
D1 = Distance at point one equals one foot
I2 = Intensity at point two ( The Unknow)
D2 = New distance of three feet OR
100 mR x (1)2 = I2 x (3) I I1 x ( D1)2
100 mR x 1 = I2 x (D2)2
100 mR = 9 I x (1) mR I (3)2
11.11 mR = I
I mR per hour

51. Using some material as a shield to reduce the radiation exposure.
SHIELDING
GAMMA RAYS
DEFINITION OF
SHIELDING
Using some material as a shield to reduce the radiation exposure.
The third concept that is stressed in radiation protection is shielding. Simply stated shielding is using some material as a shield to reduce the radiation exposure. The effectiveness of a depends on several things. They are the type of radiation and the energy level. (GAMMA, NEUTRONS, ETC.), the type of shielding material being used and the thickness of the material. Depending on the type of radiation different materials are used for shielding.
To effectively shield gamma an X rays dense materials are used commonly lead or steel are used. The shielding material used in L & P operations for density source transport shields contain lead.
To effectively shield neutrons materials which have high hydrogen contents are often used. Materials such as plastic, paraffin or water are used. The shield used for L & P Operations neutron sources are filled with a WATER EXTENDED POLYMER.
SHIELD

52. SHIELDING MATERIALS ALPHA PAPER SKIN SEVERAL INCHES OF AIR
GAMMA LEAD STEEL GOLD
BETA TIN THIN DEPLETED
ALUMINUM URANIUM
NEUTRONS WATER WAX PARAFFIN
Shielding alpha particles can be accomplished by using a sheet of paper or just several inches of air. While shielding alpha particles is rather a simple task alpha particles still can cause damage. Alpha particles because of their relatively large size have a very strong potential to ionize. Radiation causes damage by ionizing atoms in the body. While alpha particles usually don’t penetrate the skin they represent little hazard from external exposure. However sources of alpha radiation can cause a large amount of damage if they are taken in to the body. This can happen if we breathe dust which contain alpha emitting nuclides. This is a hazard associated with the uranium mining industry.
Beta particles are shielded by thin aluminum or tin. Typically beta particle will not penetrate deeply in to a human. However exposures to large sources of Beta emitting nuclides result in burns to the skin, referred to as beta burns. Source transport shields are constructed form the appropriate shielding material for the source which the shield was designed to hold. As a result one must always use the correct source/ shield combination.
NEVER USE A DENSITY SHIELD WITH A NEUTRON SOURCE AND VICE - VERSA.