Radiation Physics,Radiobiology And Regulations

Question 1

Physical properties of Radioactive and Regulations:

Answer 1

Decay of radioactivity

Question 2

Atomic Structure:

Answer 2

Composed of 3 fundamental particles; electrons, protons and neutrons. Electrons have a particle charge, protons have a positive charge and neutrons have no charge.. The nucleus contains the the protons and neutrons (nucleons). When an atom has lost or gained an electron, it is no longer electrically neutral /called an ion. When electrons are gained, the atom has an excess negative charge called a negative ion. The mass A Number represents the number of protons plus neutrons with the nucleus. The atomic Z Number represents the number of protons in the nucleus. When it charges, the densify of the atom changes. The forms of an element that have the same Z number but a different a number are called isotopes.

Question 3

Decay modes

Answer 3

Radioactivity decay, also known as a nuclear decay or a radioactivity, is the process by which the nucleus of an unstable atom loses energy by emitting radiation. Alpha-(a-decay/particle) is identical to helium Nucleus (2 protons and 2 neutrons) is released as an unstable nucleus has too many protons and neutrons. It is Carrie’s a highly ionizing electric charge (+2) which means that as the particle travels through tissue,it creates many ion pairs 7 free radicals that could be damaging to biological tissue however it has very low penetrating abilities. Beta -(B-decay) unstable nuclei having an excess number of neutrons. one of the excess neutrons is covered into a proton. The proton remains in the nucleus while the negative B particle are released. They are more penetrating than (A)but the penetration depths depends upon energy. Gamma (Y) - decay mode in which some unstable nuclei dissipate excess energy. The most common form, gamma rays( photons, or packets of electromagnetic energy, extremely short wavelength) are radiated. They are pure electromagnetic energy that can be very penetrating,depending upon the energy.

Question 4

Decay rate:

Answer 4

The rate of radioactivity substance is characterized by the following constant quantities. The half life(t1/2) what is the time taken for activity of a given amount of a radioactivity substance to decay to half of its individual value. The mean lifetime (T, “tau”) is the average lifetime of a radioactivity particle before decay.

Question 5

Half-life:

Answer 5

The time taken from the radioactivity of a specified isotope to fall it’s original value the time required for any specified property(e.g) the concentration of a substance in the body) to decrease by half.

Question 6

Parent- daughter relationship

Answer 6

Radioactivity isotopes have on stabled Nuclei. These isotopes disintegrate to form atoms with stable nuclei by the release of subatomic particles and gamma rays (akin to X-rays). The radioactivity elements are reference to a parent atoms; The atoms they disintegrate to from are called daughter products.

Question 7

Interaction of radiation with matter: photoelectric effect:

Answer 7

Occurs when an accident proton interacts with an atomic electron, to which each transfers all of the energy. The election is then ejected from the atom and will have a kinetic energy that is the difference between the energy of the incident photon and the energy that bound the electron to the atom. It is most probable for incident photons with energies less then 100 keV and emits characteristic X-rays.

Question 8

Compton Scattering:

Answer 8

A medium energy proton intervention in which the incident proton in jacks and outer shell electron having a lower binding energy. In addition to the injection electron, a low energy scattered proton is produced. It’s an ionizing type of interaction and thus, tends to be the predominant mode of interaction of diagnostic energy photons in soft tissue.

Question 9

Pair production and annihilation:

Answer 9

A high energy proton interaction in which the incident proton interacts with the intense electromagnetic field of the nucleus. The photon disappears and in its place, a electron- positron pair appears.

Question 10

Internal conversion:

Answer 10

Radioactivity decay process were in and excited Nucleus interaction with one of the orbital electrons of the atom. This causes the electron to be ejected from the atom. This is possible whenever a gamma decay is possible.

Question 11

Auger electron:

Answer 11

A physical phenomenon is which the filling of an inner shell vacancy of a atom is accompanied by the emission of an electron from the same atom.  when a core electron is removed, leaving a vacancy, an electron from a higher energy level may fall into the vacancy,resulting in a release of energy that is transferred to an outer electron ejecting it from the atom.

Question 12

Bremsstrahlung:

Answer 12

Radiation that results from the deceleration of B- particles as they approach the nuclei of lead atoms in the shield. As the particles slow down, they lose energy which is released in the form of X-rays. The amount increases with the density of the material through which the B- particles pass.

Question 13

Biological Effects of Radiation: Cellular biology

Answer 13

A branch of biology that studies the different structures and functions of the cell and focuses mainly on the idea of the cell as the base unit of life cell biology explains the structure, organization of the organelle they contain, physiological properties, metabolic processes, signaling pathways, life cycle and interactions with environment.

Question 14

Effect of radiation on cells: Direct and indirect action:

Answer 14

In direct action, the radiation hits the DNA molecules directly, disrupting the molecular structure. Such structural change leads to cell damage or even cell death. Damage cells that survive may later induce carcinogenesis or other abnormalities. This process becomes predominant with high-LET radiations such as A- particles and neutrons, and high radiation doses. In the indirect action, the radiation hits the water molecules, the major constituent of the cell, and other organic molecules in the cell, whereby free radicals such as hydroxyl(HO.) and alkoxy (RO2.) are produced. Free radicals are characterized by an unpaired electron in the structure, which is very reactive, and therefore reacts with DNA molecules to cause a molecules structure damage. It has been find that the majority of radiation-induced damage results from the indirect action mechanism because water constitutes nearly 70% of the composition of the cell.

Question 15

Radiolysis of water:

Answer 15

Exposure of cells to ionizing radiation induces high- energy radiolysis of H2O molecules into H+ and OH- radicals. These radicals are themselves chemically reactive and in turn recombine to produce a series of highly reactive combinations such as superoxide (HO2) and peroxide (H2O2) that produce oxidative damage to molecules within the cell.

Question 16

LET and RBE:Linear Energy Transfer (LET)

Answer 16

Is a physical quantity, representing the amount of energy transferred to electrons by charged particles set free by radioactive decay and/or radiation interactions in a given material (soft tissue when concerned with the potential biological impact of radiation).

Question 17

Relative Biological Effectiveness (RBE)

Answer 17

Is the ratio of biological effectiveness of one type of ionizing radiation relative to another given the same amount of absorbed energy. It is an empirical value that varies depending on the particles, energies involved, and which biological effects are deemed relevant.

Question 18

Stochastic and deterministic effects: Stochastic

Answer 18

Effects that occur by chance and which may occur without a threshold level of dose, whose probability is proportional to the dose and whose severity is independent of the dose. In the context of radiation protection, the main stochastic effect is cancer.

Question 19

Deterministic effects:

Answer 19

Have a threshold below which the effect does not occur. The threshold may be very low and may vary from person to person. However, once the threshold has been exceeded, the severity of an effect increases with dose.

Question 20

Acute effect of total body radiation: Radiation sickness:

Answer 20

Or Acute Radiation syndrome (ARS) is an acute illness cause by irradiation of the entire body ( or most of the body) by a high dose of penetrating radiation in a very short period of time (usually a matter of minutes).

Question 21

Acute Radiation Syndrome (ARS): Four stages of ARS are:

Answer 21

1: prodromal stage (N-V-D) stage) nausea, vomiting, anorexia and possibly diarrhea (depending on dose) which occur from minutes to days following exposure.

Question 22

Acute Radiation Syndrome (ARS)

Answer 22

2: Latent Stages: the patient looks and feels generally healthy for a few hours up to few weeks.

Question 23

Acute Radiation Syndrome (ARS):

Answer 23

3: Mainifest illness stage: symptoms depend on the specific syndrome and last from hours up to several months.

Question 24

Acute Radiation Syndrome (ARS):

Answer 24

4: Recovery or death: Most who do not recover will die within several months of exposure. Recovery process last from several weeks up to 2 yrs.

Question 25

Hemopoietic syndrome (Bone marrow syndrome):

Answer 25

Well usually a car with a dose between 0.7 and 10 GY( 70-1000rads) through mild symptoms may occur as low as 0.3 GY( 30 rads). Latent-stem cells in bone marrow are dying , last 1to 6 weeks. The survival rate of patients with this syndrome decreases with increasing dose. The primary cause of death is the destruction and of the bone marrow, resulting infection and hemorrhage. Recovery bone marrow cells being to re-populate the marrow, full recovery for a large percentage of individuals from a few weeks up to two years.

Question 26

Gastrointestinal syndrome:

Answer 26

Well usually cut a car with a dose greater than approximately 10 GY(1000 rads) although some symptoms May occur as low as 6GY(600 rads). Latent stem cells in bone marrow and GI tract lining are dying, last less then a week. Survival is extremely unlikely with this syndrome. Destructive and irreplaceable changes in the GI tract and bone marrow usually Cause infection, dehydration and electrolyte in balance and usually occurs within two weeks.

Question 27

Central nervous system (CNS) syndrome:

Answer 27

Well usually a car with a dose greater than approximately 50 GY(5000 rads) although some symptoms may occur as low as 20 GY( 2000rads). Death occurs within three days and is likely due to collapse of the circulatory system as well as increased pressure in the confining cranial vault as the result of increased fluid contact caused by edema, vasculitis and meningitis.

Question 28

Long term effect of radiation: Somatic

Answer 28

Significant amounts of tissue is affected due to radiation damage. A shot-term dose of 200 to 300 rads can result in sunburn like injuries to the skin with accompanying hair loss. At doses over 1,000 rads, the gastrointestinal system suffers upset, including nausea, electrolytes imbalance and other symptoms. In excess of 5,000 rads, the nervous system undergoes shock, leading to confusion, loss of coordination or coma due to internal bleeding and pressure in the brain. Delayed, longer term somatic effects include the possible development of tumors, cancer and cataract’s.

Question 29

Long term effect of radiation: Genetic

Answer 29

Although ionizing Radiation can damage DNA, genetic abnormalities are not passed onto the next generation being at an Significant rate. Only a few radiation causes genetic disorders are believed to occur per million live births. However, if a pregnant woman is exposed to radiation, the development tissues in the fetus are vulnerable particularly in the brain and nervous system, exposes may lead to mental retardation and other serious conditions.

Question 30

Relative tissue and organ sensitivity:(Ex, law of bergonie and Tribondeau..

Answer 30

A fundamental law of radiation biology that states that the ratio sensitivity of a tissue is increase the greater The number of undifferentiated cells in the tissue, the greater the mitotic activity, and the greater the length of time that they are actively proliferating.

Question 31

Effects of radiation on embryo/fetus:

Answer 31

Because the human embryo or fetus is protected in the uterus, and radiation dose to the fetus tends to be lower than the dose to its mother for most radiation exposure events. however, the Human embryo and fetus are particularly sensitive to ionizing radiation, and the Health consequences of exposure can be severe. Such consequences can include growth retardation, malfunctions, impaired brain function, and cancer..

Question 32

Effects of radiation on embryos/fetus

Answer 32

1: 0:05 GY (5 rads) non-cancer health effects not detectable. Estimated childhood cancer equals 0.3-1% 2: 0:05-0:50 GY(5-50 rads): failure to implant my may increase sensitivity, incident of major malfunctions, may increase slightly and growth retardation possible. Estimated childhood cancer = 1-6%. 3: .50 GY (50 rads): failure to implant will likely be large depending on those, incidence of miscarriage may increase depending on those,substantial risk of major malformations such as neurological and motor deficiencies, growth retardation likely. Extimated childhood cancer=>6%.

Question 33

Basic concepts of Radiation protection: unit of radiation exposure:

Answer 33

There are four different but but interrelated units of measuring radioactivity, exposure, absorption dose, and dose equivalent(READ). Radioactivity references to the amount of ionizing radiation releases by a material. Whatever particles are released, is expressed in terms of its radioactivity which represents how many atoms in the material decay in a given time period.

Question 34

Unit of radiation exposure: Units of measure:

Answer 34

Curie (Ci) and becquerel (Bq). Exposure describes the amount of radiation traveling through the air.

Question 35

Units of radiation exposure: unit of exposure:

Answer 35

Roentgen (R) and coulomb/kilogram (C/Kg). Absorbed dose describes the amount of radiation absorbed by an object or person.

Question 36

Unit of radiation exposure: Unit for absorbed dose:

Answer 36

Radiation absorbed dose (rad )and (gray )(GY). Dose elevation (or effective dose) combines The amount of rad absorbed and the medical affects of the type of rads. For B and Y radiation, the dose elevation is the same the absorbed dose. The dose elevation is larger than the absorbed dose for (a)and neutron radiation because these types are more draining to the human body.

Question 37

Unit of radiation exposure: unit for dose equivalent:

Answer 37

Roentgen equivalent man (rem) and sievert (SV) and biological dose equivalents are commonly measured in 1/1000th of a rem(rem) ( dose equivalent).

Question 38

Principals of time, distance and shielding:

Answer 38

There are three general guidelines for controlling exposure to ionizing radiation, minimizing exposure time, maximizing distance from the radiation source, shielding yourself from the radiation source.

Question 39

Time:

Answer 39

The amount of radiation exposure increase and decrease what’s the time people spend near the source of radiation.

Question 40

Distance:

Answer 40

The further away people are from radiation sources, the less they’re exposed. Doubling the distance from a point source for radiation decreases the exposure rate to 1/4 The original exposure. Having the distance, increases exposure by a factor of four.

Question 41

Shielding

Answer 41

The placement of an absorber, between you and the exposure source. Alpha, beta or gamma radiation can all be stopped by difference thickness of absorption. (A )particles a fin piece of paper, or even the dead cells in the outer layer of human skin provides adequate Shielding because alpha particles can’t penetrate it. Heart ever, living tissue inside the body often’s nose attacks in against and healed or ingesting alpha mirrors. (B) particles stopped after traveling through about 10 feet of air less than 2 inches of water, or a thin layer of glass or metal. Additional covering, for example heavy clothing, is necessary to protect against beta emitters. (Y) particles to reduce by a factor of billions, fitness needs to be about 13.8 feet of water, 6.6 feet of concrete or 1.3 feet of lead. Thick, dense shielding is necessary, the higher the energy of the GammaRay, the thicker the shield must be. X-rays pose a similar challenge as why teach give patience receiving x-rays a lead apron to cover.

Question 42

Personal protection equipment

Answer 42

Ex: gloves, lab coats

Question 43

Personal monitoring devices: Film badges:

Answer 43

A plastic holder in which a strip of photographic film is held between a set of filters. Amount of darkening density on the film is held between a set of filters. Three or four filters made of a different material( lead, copper, aluminum, plastic) so energy range and penetration can be assessed. effective in measuring exposes of 0.1millisevert (mSv) (10mrem) to several sieverts/serveral hundred rem. Affected by heat and moisture.

Question 44

Personal monitor devices: Thermoluminescent Dosimeters (TLD)’s

Answer 44

Uses lithium fluoride crystals that emit a quantity of light proportional to the amount of rad absorbed by the crystals. Light is measured when they are heated. Though more expensive, it is not affected by environmental conditions.

Question 45

Optically stimulated Luminescence Dosimeter (OSL)’s:

Answer 45

Uses A thin slice of aluminum oxide to detect exposure. It is more sensitive than a film badge, is resistant to heat, moisture and aging, can be used for up to three months.

Question 46

Pocket ionization chamber:

Answer 46

Amount of ionization is directly related to the amount of exposure and measurements are provided immediately, expensive compared to film and TLDS.

Question 47

ALARA:

Answer 47

An acronym for “as low as(is) reasonable achievable, which means making every reasonable effort to maintain exposure to ionizing radiation as far below the dose limits as practical, consistent with a purpose for which the license activity is undertaken, taking into account the state of technology, the economics of improvements in relation to state of technology, The economics of improvements and relation to benefit to the public health and safety, and other societal and socioeconomic considerations, and in relation to utilization of nuclear energy and license materials in the public interest.

Question 48

Release of patients:

Answer 48

A person who has received a therapeutic dose of RPHKMB released if it is determined that no individual in contact with the patients will receive more than 5MSV(0.5rem). If any person is likely to receive more than 1 mSv(0.1rem) from the patient, then the patient must be given written instructions on hard to minimize exposure to others.

Question 49

NRC Regulations for radiation exposure: NRC radiation exposure Limits, Millisieverts(rem):

Answer 49

Whole-body TEDE ( Total Effective Dose Equivalent) - 50(5) per year Lens of any eye (LDE) - 150(15) per year Any Organ or tissue TEDE-500(50) per year Skin or any extremely (SDE)-500(50) per year. Member of the general public TEDE - 1(0.1) per year. Embryo/fetus of occupationally exposed worker -5(0.5) entire pregnancy.

Question 50

Internal dosimetry and bioassays: Internal dosimetry:

Answer 50

The science and art of internal ionizing radiation dose assessment due to radionuclide incorporated inside the human body. Radionuclides deposited within a body will irradiated tissues and organs and give rise to a committed dose until they are excreted from the body or the radionuclide is completely decayed.

Question 51

Bioassays:

Answer 51

Any measurements of radioactivity that has been internalized by an individual. This May be done as external counting or counting biological sub tools such as urine, blood or others fluids. monitoring of thyroid uptake is required if there is a possibility that inhaled activity exceeds NRC limits.

Question 52

Personnel exposure records: Medical Events: Definition:

Answer 52

A radiopharmaceutical (rph) misadministration either through error and excess exposure. Both must happen for a medical event to occur.

Question 53

Personnel exposure records: Medical Events: NRC regulations for reporting and notification: Errors:

Answer 53

The dosage is administered to the wrong person, the dosage is administered by the wrong root, or the dosage differs from the prescription by more than 20% or falls outside the percentage range.

Question 54

NRC Registration for reporting and notification Errors: Excess:

Answer 54

50mSv(5rem) effective dose equivalent, 500mSv(50rem) to any organ or tissue, or 500mSv(50rem) SDE to skin.

Question 55

Area/ Facilities monitoring: Basic Concepts: Unrestricted

Answer 55

Access is not limited by or under the direct control of the license, less than 0.0 2MSV(2mrem) in an hour, if exceeded, then area is restricted.

Question 56

Caution, radioactive materials: 

Answer 56

Using to indicate any area where contains quantities of radioactivity Materials are stored. Find an entrance, indicate potential presence of radiation sources/contamination, food or drinks prohibited, No smoking or cosmetics allowed.

Question 57

Cautions radioactivity materials:

Answer 57

Exceeds: 10mci Tc -99m, TI 201, Ga-67, Xe-133, Cr-51 Exceeds: 1mCi:In-111,I-123,Sm-153,Mo-99,Co-57 Exceeds: 100uCi: Sr-89, P-32, Cs-137 Exceeds: 10 uCi: I-131, I-125

Question 58

Caution radiation area:

Answer 58

Could receive more than 0.0 5MSV(5 mrem) In one hour at 30 cm commonly seen at the entrance to the Nuc med labs.

Question 59

Caution: high radiation area

Answer 59

Could receive more than 1 mSv(100mrem) in 1 hr at 30 cm commonly seen in areas where radiation therapy is performed.

Question 60

Caution very high radiation area:

Answer 60

Could receive more than 5GY(500rad) in 1 hr at 1M. Not commonly seen in the hospital settings.

Question 61

Survey equipment and techniques: well counters.

Answer 61

Use a NaI(TI) crystal to detect very low activates of radioactivity. It’s significantly more efficient then a gamma camera since the radioactive sample is placed into a well bored into a thick cylinder of crystal. Sensitivity limits instrument’s use b/c activities greater than 74 KBq (2uCi) can cause: COINCIDENCE-LOSS: when too many photons strike the crystal, quarts are lost in the dead time.

Question 62

Survey equipment and techniques: Survey Meters:

Answer 62

Used to measure radiation exposure.

Question 63

Geiger-Mueller(G-M)

Answer 63

Counter is used to survey/detect contamination. It is appropriate due to its rapid response time and can detect a wide range of exposure rate due to its multiple skills. They can be filtered with a end window or pancake probe. The ending -window must be pointed directly at the source of accurate detection. The Pancake allows for the survey of larger area. G-M are not as accurate as portable ionization meters or Cutie pies. It has it has a longer response time so the exposure rate is based on more data and thus, more accurate. So, it is superior to the G-M when measuring high dose rates and most useful for determining the exposure rate produced by a parent who has received a therapeutic dose.

Question 64

Wipe test technique:

Answer 64

To detect very low levels of removable contamination using a well Conner. It can detect activity below the background levels seen with a GM counter..

Question 65

NRC regulations: frequency of surveys and wipes:

Answer 65

Personnel must survey their hands and feet before leaving the facility and should before a meal. Surveys must be performed at the end of the day whenever therapeutic doses are administered. Areas where the dosage was prepared administered must be surveyed. 

Question 66

Frequent of surveys and wipes: Restricted

Answer 66

No more than 0.05MSV/hour(5 mrem/hr) and 2 uSv/hr (0.2mrem/hr).

Question 67

Frequent of surveys and wipes: unrestricted:

Answer 67

Routine wipe tests are performed using the same criteria. Wipe test frequency should be increased whenever survey frequency is increased. no more than a trigger level of 22 DPM per centimeter of contamination and either who restricted or on restricted area.

Question 68

Classification of areas: work

Answer 68

Where the Nuclear medicine technology would work.

Question 69

Classification of areas:  treatment

Answer 69

Where a patient would receive treatment in a nuclear medicine department.

Question 70

Classification of areas: Storage

Answer 70

Rph’s with a half life of less than 120 days can be restrained in a shielded area until they have decayed to a level of activity that equals background. One would decay the product for at least 10/2 lives before discarding it in regular or biohazard trash= (rule of thumb). When placed in storage, it should be labeled with the date, identify of the longest life lived or PH and separated based upon half life. After decaying to BKG levels, it can be disposed of as regular garbage. If the waste contains potentially biohazardours Materials( needle, syringe), it should be discarded with other biomedical waste.

Question 71

Posting of signs:

Answer 71

Ex types, locations

Question 72

Documentation of surveys and wipes results:

Answer 72

1: interpretation 2: Reporting ( corrective action) 3: Record retention: NRC regulations state 3 years for surveys. Must include the date, results, instrument and name of individual who performed it.

Question 73

Radioactive Spills: Major Spills:

Answer 73

Wild spread areas of contamination or a high radiation dose rate. 1: clear the area, notify all personnel not involved with the spell to leave the area. 2: use absent paper to prevent spread of contamination but do not clean up the spill. 3: limit movement of contaminated personal to prevent spread of contamination, removing contaminated clothing before leaving the area. 4. Evaluate/ close all doors to area, lock the doors or secure area to prevent entry. 5: notify the RSO immediately as clean/decontamination should be conducted under their supervision. 6. If ski is contaminated, wash asap with warm water and soap. 

Question 74

Radiation Spills: Minor Spills:

Answer 74

Hey small area or related low radiation dose rate. 1: Notify all persons in immediate Vicinity that he still has occurred. 2: contain the spell by placing absorbed material over liquid limit movement in the area on tell expect of spell is known/area is of isolated. 3: if clothing is contaminated remove it before leaving. If skin is contaminated, wash it ASAP with warm water and soap. 4: wear appropriate PPE such as disposable gloves and shoes coverings. 5: place all materials used to clean into plastic bag and dispose of them as radioactivity waste. 6: use survey meter and wipe test to determine rather all contamination has been removed. 7: use absorbed paper and/or shielding to cover the area of the spell if activity remains after decontamination. Label with caution, radioactivity material. 8: Report spell to the RSO.

Question 75

Radiation Spills: minor Spills:

Answer 75

C: processes for decontamination D: Reporting Procedures

Question 76

Radioactivity materials:

Answer 76

1: Inspection of incoming and outgoing materials( EX: DOT and NRC regulations)

Question 77

Radioactive materials: shipping labels: 

Answer 77

``` DOT I ( White): At contact, no more then 0.5 mR/hr. At 3 feet,no detected Radioactivity (NDR) DOT II (yellow): At contact, no more then 50 mR/hr. A 3 feet,no more then 1mR/hr. DOT III(yellow) : At contact, no more then 200 mR/hr. At 3 feet, no more then 10 mR/hr. ```

Question 78

Radioactivity materials:

Answer 78

B: measurements of exposure rate C: measurements of surface contamination. D: removable contamination limits/ trigger levels. E: documentation hale for 3 years

Question 79

radioactivity materials: storage:

Answer 79

where Radio pharmaceuticals or contamination after use or mistake is stored.

Question 80

Storage: Radiopharmaceuticals:

Answer 80

 radioactivity materials that are being stored for later, must be shielded to minimize radiate activity levels. Vital Scheels and lead breaks usually provide sufficient protection. Vital Scheels and syringe Scheels must be labeled for identification. Contain RPHS may have additional storage recommendations. EX, liquid radioactivity sodium iodine must be kept refrigerated. Dose of high 131 should be prepared under a fume hood.

Question 81

Storage:

Answer 81

B: sealed sources C: consequences of improper storage

Question 82

Disposable of radiation waste: Release to environment: 

Answer 82

The amount of solvable waste that can be discarded into the sewage system is based upon the rate of water waste discharge from the facility. Radioactivity urine and feces are exempt from any limitation.

Question 83

Disposable of radiation waste:Decay in storage

Answer 83

Where they would put waste from radiopharmaceuticals after use or contamination happens. Has to be in decay storage for 10 times before removing to regular waste and must be checked be for taken to regular waste.

Question 84

Disposable of radioactivity waste: transfer to authority recipients

Answer 84

On used unit dosages and used dosage receptacles are usually return to the radiopharmacy. Long life Radioactivity waste can be disposed by transferring it to an authorized waste handler who lets berries or incinerates the waste.

Question 85

Disposal Pharmaceuticals:

Answer 85

1: Expired pharmaceuticals, same as decay and storage. 2: partial used pharmaceuticals, same as decay and storage.

Question 86

Linear amplifier:

Answer 86

The pulse is further, amplified and properly shaped by a linear amplifier. The amplified pulse is the delivered to a pulse height analyzer for analysis as to its voltage.

Question 87

X/Y positioning Circuits:

Answer 87

When a Y Ray interacts in the Crystal, it’s exact Location is determined by the X/Y positioning Circuit with the PM tubes. The X/Y positioning circuit sums up the output of different tubes and products X and Y pulses in the direct proportion to the X/Y coordinates of the point of interaction of Y rays. Thus, gives image of the dispute Ment of activity in the source and stored in the computer for future processing. Larger the number of p.m. tubes, better the deception on the image of the X/Y coordinates Point of Y Ray interaction( better imaging resolution). Also, higher the Y ray energy, better the Resolution do two more light in the Crystal. However, very high energy race can penetrate the collimator septa and blur the image. Low energy rays will scatter more causing poor resolution.

Question 88

Pulse height analyzer (PHA):

Answer 88

A circuit that sums up the output of all p.m. tubes to produce a pulse known as the pulse that represents the energy of a Y Ray. The single channel analyzer ( SCA) analyzes the amplitude of the Z pulses and selects those only of desired energy by use of appropriate Peak energy and window settings. In most cameras, the energy selection is done with a push of a button from different radionuclides. (X/Y pulses are accepted only if the Z pulse is within the energy range by the PHA. If Z pulses are outside the range, the X/Y pulses are discarded.

Question 89

Quality control:

Answer 89

1: frequency and types of checks 2: Performance Characteristics.