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					 TEXAS SOUTHERN
   UNIVERSITY

RADIATION SAFETY
 TRAINING GUIDE

RADIATION SAFETY COMMITTEE
        Version 2005/2006
Objectives:
1)     Address basic topics and principles of radiation safety and apply them to the use of
       radioactive sources in research at Texas Southern University, Houston.

2)     Address Texas regulatory requirements for radioactive material use at Texas Southern
       University.

3)     Address procedures for receipt, use, storage, and disposal of radioactive material at Texas
       Southern University complying with the Safety Manual at Texas Southern University.


This manual was adapted from the radiation safety training guide for the University of Texas
Health Science Center at Houston.



Marian Hillar, M.D., Ph. D.
Radiation Safety Officer
Department of Biology
Texas Southern University
                                                       TABLE OF CONTENTS

1.0 INTRODUCTION....................................................................................................................1
  1.1 Purpose ..................................................................................................................................1
2.0 SOURCES OF RADIOACTIVITY ........................................................................................5
  2.1 Natural Radioactivity ..............................................................................................................5
  2.2 Occupational Radioactivity ....................................................................................................7
  2.3 Nuclear Fuel Cycle .................................................................................................................7
  2.4 Consumer Products .................................................................................................................7
  2.5 Medical ...................................................................................................................................7
  2.6 Miscellaneous .........................................................................................................................8
3.0 FUNDAMENTALS OF RADIOACTIVITY .........................................................................8
  3.1 Components of an Atom .........................................................................................................8
  3.2 Radioactive Decay ..................................................................................................................8
       Alpha decay ...........................................................................................................................8
       Beta decay .............................................................................................................................9
       Gamma Rays..........................................................................................................................9
  3.3 Units........................................................................................................................................9
       DPS, Bequerel, Curie ............................................................................................................9
       Roentgen ..............................................................................................................................10
       Rad, Gray ............................................................................................................................10
       Rem, Sievert .........................................................................................................................10
  3.4 Half-life ................................................................................................................................11
  3.5 Inverse Square Law ..............................................................................................................12
4.0 BIOLOGICAL EFFECTS ....................................................................................................12
  4.1 Dose-Effect Models for Response ........................................................................................13
       Linear Response Model .......................................................................................................14
       Linear Quadratic Response Model......................................................................................14
       Threshold Response Model .................................................................................................14
  4.2 Radiation Protection .............................................................................................................14
  4.3 Law of Bergonie & Tribondeau ............................................................................................15
5.0 EXPOSURE LIMITS & PERSONNEL MONITORING ..................................................15
  5.1 Personnel Monitoring/Dosimetry .........................................................................................15
       Film Badges .........................................................................................................................17
       TLD Badges .........................................................................................................................17
       Finger Ring Badges .............................................................................................................17
  5.2 General Rules for Use of Personnel Monitors ......................................................................18
  5.5 Prenatal Radiaton Exposure ..................................................................................................18
       Prenatal Radiation Exposure as Compared to Other Risks ....................................................
         The Decision of the Mother .................................................................................................................................
      6.0 LABORATORY PROCEDURES .............................................................................................................. 22
   6.1 Postings and Labels ..............................................................................................................22
   6.2 Receipt and Inventory of Radioactive Material ....................................................................22
   6.3 Approval for Orders of Radioactive Material22

                                                                                iii
  6.4 General Radiation Safety Guidelines ....................................................................................22
       Radiation Sources................................................................................................................24
       Radiation Producing Electronic Equipment .......................................................................26
  6.5 Radiological Health Surveys ................................................................................................26
  6.6 Waste Disposal .....................................................................................................................27
       Solid Waste ..........................................................................................................................28
       Liquid Scintillation Vials .....................................................................................................28
       Biological Waste..................................................................................................................28
       Liquid Waste ........................................................................................................................29
  6.7 Instrumentation .....................................................................................................................29
       Geiger-Mueller Survey Meter..............................................................................................29
       Scintillation Counter ...........................................................................................................30
       Liquid Scintillation Counter ................................................................................................30
7.0 EMERGENCIES....................................................................................................................30
  7.1 Emergency Response ............................................................................................................30
       Radioactive Spill.................................................................................................................30
8.0 RULES, REGULATIONS, RIGHTS, AND RESPONSIBILITIES ..................................31
  8.1 Texas Southern University's Responsibility ........................................................................31
  8.2 Employee's Responsibility ...................................................................................................31
  8.3 What is Covered by these Regulations ................................................................................31
  8.4 Reports on Your Radiation Exposure History .....................................................................31
  8.5 Inspections by Texas Department of Health ........................................................................32




                                                                      iv
1.0 INTRODUCTION

1.1 Purpose

The Radiation Safety Committee exists to establish and maintain a radiologically safe and
healthy environment for all students, faculty, staff and visitors to Texas Southern University at
Houston. An essential component of the radiation safety program is the training of personnel in
the safe manipulation and disposal of radiation sources. This text supplement, in conjunction
with the classroom sessions, is intended to provide a familiarization with the issues related to
radiation safety and is not meant as a comprehensive manual. It is important to understand that
the authorized user of radioactive material is the individual directly responsible for the training of
subordinates and compliance with the rules and regulations governing usage of sources. The
Radiation Safety Committee and Radiation Safety Officer are available to provide the assistance
and consultation required to maintain a safe and healthy radiological environment.

The Radiation Safety Committee Chair and Radiation Safety Officer can be reached at the
following number:s

Amruthesh Shivachar
Radiation Safety Committee Chair :    713-313-1896
School of Pharmacy, Gray Hall, room 214 A

Marian Hillar
Radiation Safety Officer :              713-313-7990
Department of Biology, Science Hall, room 228

2.0 SOURCES OF RADIOACTIVITY

2.1 Natural Radioactivity
Exposure to radiation is unavoidable. The National Council for Radiation Protection (NCRP)
issued Report 93 (1987) which summarized recent exposure data of U. S. residents from all
sources of radiation. The sources are broken down into six categories: Natural Sources,
Occupational, Consumer Products, Nuclear Fuel Cycle, Medical, and Miscellaneous. About
82% of the U.S. average background dose is due to natural sources. The remaining 18% is due to
the other five categories. Figure 1 shows the different source contributions.




                                                  5
                             Figure 1: Sources of background radiation.


Background radiation is primarily caused by trace quantities of naturally occurring
radionuclides in the earth's crust. The largest contributor is 226Ra, with significant levels also
from 238U (Uranium), 232Th (Thorium), and 40K (Potassium). Concentrations of these
radionuclides vary with the type of rock formations. Igneous rock contains the highest
concentration (125 mrem/yr) followed by sedimentary, sandstone (50 mrem/yr) and limestone
(25 mrem/yr). The average annual dose in the U.S. is about 40 mrem from the earth's crust.

These naturally occurring radionuclides also exist in food, water, and air, which subsequently
enter the body. The radionuclide may then decay inside the body, irradiating tissues usually
protected by the skin. In the U.S., about 80% of this internal radiation dose is received from 40K,
a weakly radioactive isotope of potassium. Potassium is a crucial constituent of biological
systems, thus the high contribution.

Radon-226 gas represents the most important contributor to the background dose in the U.S.
Because radon is a noble gas it is not easily incorporated into the human body. It irradiates by
decaying when trapped inside the human lung. The sensitive lung cells are then unprotected by
the skin. Radon gas in soil and building materials seeps out into the air. Therefore, the annual
dose from Radon gas depends on the soil type and building material of your home. In Texas, the
annual contribution from radon gas is approximately 275 mrem.

Cosmic rays are another component of the natural radiation field. Charged particles from our
solar system and other galaxies bombard the earth's atmosphere with energies up to 1014 MeV.
At the top of the atmosphere, nearly 87% of these incident particles are protons, 11% are helium
nuclei, and the remaining 2% comprise the rest of the elements on the periodic table. These
high-energy ions interact while traveling through the atmosphere. Thus, at sea level, the cosmic
radiation is comprised of 63% mesons, 21% neutrons, and 15% electrons.

                                                 6
The dose from cosmic rays is latitude and altitude dependent. Traveling higher into the
atmosphere decreases the amount of atmosphere that acts as shielding, which results in a higher
annual dose. At sea level, the average annual dose is around 30 mrem, while 140 mrem/yr is
expected at an altitude of 10,000 ft. Due to the unique shape of the earth's magnetic field, the
contribution from cosmic rays increases from the equator towards the poles. The dose increases
8% from the equator to the northern extent of the contiguous U.S. (50o-north latitude).

2.2 Occupational

Those people who receive dose as a necessary byproduct through their job performance receive
occupational exposures. Occupations using radiation as a tool include medical imaging,
biomedical science research, industrial radiography, well-loggers, nuclear power plant workers,
Dept. of Energy workers, and uranium miners. Other occupations which work in areas of higher
natural backgrounds are aircraft personnel (due to cosmic rays) and coal miners (from high levels
of radon gas).

2.3 Nuclear Fuel Cycle

The nuclear fuel cycle broadly encompasses the industrial processes beginning with uranium ore
to producing electricity in nuclear power plants. The average annual dose to the public from the
nuclear fuel cycle is approximately 5 mrem. This includes all phases in the process from mining
the uranium, processing, use, and reprocessing/waste storage. The annual dose from these
processes is highly localized. Typically, only people living within 50 miles of a portion of the
cycle (e.g. uranium mine, mill, or a nuclear powered generating station) receive any measurable
dose.

2.4 Consumer Products

Many consumer products contain radionuclides inherent in their function or as side-products.
For many years, luminous dials utilized radionuclides like 226Ra, 3H, and 147Pm (Promethium).
Even today, smoke detectors depend on small quantities of 241Am (Americium) for their
operation.

Tobacco products contain significant levels of 210Pb (Lead) and 210Po (Polonium). The NCRP
estimated that smoking 1.5 packs per day delivers a dose to the lungs of 8,000 mrem/yr. This is
100 times higher than the natural background levels and 16 times higher than the maximum
permitted whole body dose.

2.5 Medical

Medical sources include diagnostic procedures such as X-rays (medical and dental)
mammography, fluoroscopy, CT scans, radiation therapy, and other nuclear medicine procedures.

                                               7
 Dose rates from medical exposures are considerably higher, and generally less protracted than
those from environmental or routine occupational sources. The average annual effective dose
equivalent from diagnostic x-rays to the U.S. population is 40 mrem.

2.6 Miscellaneous

Miscellaneous sources of exposure to the general public come from air emissions from Dept. of
Energy facilities not accounted for earlier, Nuclear Regulatory Commission (NRC) licensed and
non-DOE federal facilities, excluding nuclear fuel cycle facilities, and certain mineral extraction
facilities. The exposures from transportation of radioactive materials and from fallout of past
nuclear weapons testing are also considered under this category.

3.0 FUNDAMENTALS OF RADIOACTIVITY

3.1 Components of an Atom

The basic components of the atom are the proton, neutron, and electron. The positron or anti-
electron is important in PET (Positron Emission Tomography) studies but is not a common
atomic particle. The particular combination of protons and neutrons determines not only what
the element is, but also which isotope of the element is present. The number of protons
determines the identity of the element, and the number of neutrons determines the isotope of that
element. Atoms are radioactive when there is an unstable nucleus with an excess of energy.

3.2 Radioactive Decay

The reason atoms are radioactive is because the ratio of neutrons to protons is not ideal. Through
radioactive decay, the nucleus approaches a more stable neutron to proton ratio. Radioactive
decay releases different types of energetic emissions. The three most common types of
radioactive emissions are alpha particles, beta particles, and gamma rays. X-rays differ from
gamma rays only in how they are produced in the atom. X-rays are atomic phenomena whereas
gamma rays are nuclear phenomena, but the two are indistinguishable once they have left the
atom. Several other types of radioactive decay exist: fission, positron decay, and electron
capture. These processes are not generally encountered in the laboratory environment and will
not be discussed in this text.

Alpha decay
Alpha decay occurs when the neutron to proton ratio is too low. Alpha decay emits an alpha
particle, which consists of two protons and two neutrons. This is the same as a helium
nucleus, and often uses the same chemical symbol 4He. Alpha particles are highly ionizing (e.g.
deposit energy over a short distance). Since alpha particles lose energy within a short distance,
they cannot travel far in most media. For example, the range of a 5 MeV alpha particle in air is
only 3.5 cm. Consequently, alpha particles will not normally penetrate the outermost layer of the
skin. Therefore, alpha particles pose little external radiation field hazard. Shielding of alpha

                                                8
particles is easily accomplished with minimal amounts of shielding. Examples of alpha
particle emitting radionuclides include 238U, 239Pu (Plutonium), and 241Am.

Beta decay
Beta decay occurs when the neutron to proton ratio is too high. The radioactive nucleus emits a
beta particle, which is essentially an electron, in order to bring it to a more favorable ratio.
Beta particles are less ionizing than alpha particles. The range of beta particles depends on the
energy, and some have enough to be of concern regarding external exposure. A 1 MeV beta
particle can travel approximately 12 feet in air. Energetic beta particles can penetrate into the
body and deposit dose to internal structures near the surface. Since beta particles are less
ionizing than alpha particles, greater shielding is required. For example, 32P can be effectively
shielded by 1/4 to 3/8 inches of Plexiglas. It is important to shield beta particles with low z
materials (e.g. aluminum or acrylic) to prevent x-ray emissions as the electrons slow down. This
is a phenomenon known as bremsstrahlung.

Gamma Rays
Gamma rays are not particulate radiation like the alphas and betas, but are a form of high-energy
electromagnetic waves. Gamma rays are the least ionizing of the three forms discussed. In fact,
gamma rays are only an indirect form of ionizing radiation. This means that gamma rays must
interact with the atoms in the material first, and these interactions create charged particles. A 1
MeV gamma ray can travel an average of 130 meters in air. Since gamma radiation can travel far
in air, it poses a significant external radiation hazard. Further, if ingested, it may pose an internal
radiation hazard. Shielding of gamma rays is normally accomplished with high atomic
number materials such as lead.

3.3 Units

DPS, Becquerel, Curie
There are several different units used to describe radiation and its effects. The least complex unit
is that of activity, which is measured in disintegrations per second, dps. One dps means a
radioactive nucleus gives off one particle or wave in one second. This unit does not distinguish
between alpha, beta, or even gamma. This unit, in the international system of units, SI system,
is called the Becquerel, Bq, which is equivalent to 1 dps. The historic predecessor of the Bq, the
Curie, Ci, can be equated to the Becquerel and dps.

                                                1 dps = 1 Bq
                                             1 Ci = 3.7x1010 Bq

These units provide an understanding of the “strength” of a radioactive sample but do not
account for any of the properties of the radiation emitted. For example, 250 Ci is a considered a
small activity, while 250 Ci is a very high activity. To describe the degree of hazard to people
from a particular radiation requires other units.


                                                  9
Roentgen
The roentgen, R, is a unit of exposure. This unit is only appropriate for electromagnetic
radiation (e.g. gamma rays and X-rays); it does not apply to alpha and beta particles. The
roentgen is the measure of ion pairs created in air. One roentgen is equal to 1 electrostatic
unit per cubic centimeter of air at STP.

                               1 R = 1 esu/cm3 or
                                   = 2.083 x 109 ion pairs/cm3

The new SI convention for the measure of exposure is the coulomb per kilogram of air, C/kg.
This unit gives some information about the type and "strength" of the radiation field but is still
vague regarding damage or risk to humans and materials.

Rad, Gray
The rad is an acronym for Radiation Absorbed Dose. It is a measure of the amount of energy
deposited per unit mass in a material. Specifically, one rad is equal to one hundred ergs of
energy deposited per gram of material.

                                    1 rad = 100 erg/gm; also

                            1 rad = 0.876 R for gamma and X-rays

In many radiation protection calculations, one rad is approximately equal to one roentgen.
However, more accuracy is required in radiation therapy applications. The SI unit for absorbed
dose, or rad, is the Gray, Gy, where:
                                       1 Gy = 100 rad

The rad measures energy deposited per unit mass of a material by a particular type of
radiation. This relates the amount of damage that occurs to a living organism by the radiation
but does not account for different ionizing capabilities of radiation types, i.e. gamma versus
alpha.

Rem, Sievert
The rem stands for Radiation Equivalent Man (or Mammal). It measures the risk of damage
to living tissue for a specific type of radiation. This unit accounts for the varying parameters of
the radiation (energy, type, stopping power, etc.). The rem is equal to a rad multiplied by a
quality factor, Q. This quality factor depends on the type and energy of the radiation (i.e. alpha
or gamma).

                                       1 rem = 1 rad x Q



                                                10
The Texas Administration Code (TAC) establishes the following quality factors, Q.
                         Type of Radiation                   Q
                         X-rays and gamma rays                1
                         Beta particles                       1
                         Neutrons of unknown energy          10
                         High-energy protons                 10
                         Alpha particles                     20
The SI unit for the rem is the Sievert, Sv, where:
                                              1 Sv = 100 rem

The rem measures the damage to humans for all radiations at varying energies. Dose
equivalent is the unit of dose that is most important in radiation safety. All legal doses in
radiation protection are recorded in rem or Sv.

3.4 Half-life
Since radioactive atoms decay, the number of radioactive nuclei in a finite sample decreases with
time. This decay obeys a logarithmic decay that can be expressed by the following equation:

                                                A = Ao e-t

Where Ao is the initial activity,  is the decay constant, and t is the time. The decay constant is a
physical property of that radionuclide and does not change. The decay constant basically
measures the probability that a nucleus will decay in one second. The larger the decay constant
the more probable the nucleus will decay in one second. A useful parameter to describe how
long an isotope will last is the half-life, T1/2. The half-life is the time it takes for a sample of
radioactive atoms to decay to one-half of the initial value. After one half-life, only half as
much as the original amount remains. After two half-lives there is (1/2)( 1/2) =  of the original.
The half-life and decay constant are related by the simple equation:

                                               T1/2= 0.693/

As an example, 32P has a half-life of approximately 15 days. Determine how much of a 50 mCi
sample is left after a month and a half. This can be done by substitution into the above
equations, or easily estimated as follows. 1.5 months = 45 days, T1/2= 15 days; therefore, 45 days
= 3 half-lives.
    After one half-life there is (0.5) (50 mCi) = 25 mCi
    After two half-lives there is (0.5) (25 mCi) = 12.5 mCi
    After three half-lives there is (0.5) (12.5 mCi) = 6.25 mCi

                                                 Or
   (50 mCi)(0.5)(0.5)(0.5) = 6.25 mCi


                                                 11
From this we gather the important concept here that samples decay away with time. Many of the
isotopes commonly used in lab experiments have short half-lives and will decay to low levels in
a few months.

                   Radionuclide                       Half-life
                   32
                     P                                14.3 days
                   35
                     S                                87.2 days
                   125
                      I                               60.1 days
                   3
                     H                                12.3 years
                   14
                     C                                5730 years

3.5 Inverse Square Law

An important concept for reducing exposure to radiation is the inverse square law. This states
that as the distance from a radiation source increases, the intensity decreases as the square
of the distance. Moving twice as far away from a source reduces the exposure by a factor of 4.
Therefore, distance can be used effectively as a "shield" from radiation. Thus, even small
increases in distance can greatly reduce the radiation field.

For example, if the radioactive waste container in the lab is kept one foot away from the
workstation, how much will the exposure be reduced if the waste container is moved to a corner
of the lab 6 feet away.
Solution: the distance is increased from 1 to 6 feet, this is a factor of 6 times. The inverse square
law says that the intensity will decrease by the square of this, which is 62 = 36. By moving the
waste container to the corner of the lab, the exposure to persons at the workstation has been
decreased to 1/36.

The inverse square law dictates the use of increased distance between the user and the radiation
source. This can be accomplished with tongs, tweezers, pipettes, or pliers. Also, it is prudent to
place your radioactive waste as far away as possible to make use of the inverse square law.

4.0 BIOLOGICAL EFFECTS

Radiation effects on humans can be considered as either somatic or genetic. Somatic effects
manifest themselves in the exposed individual, while genetic effects are displayed in offspring.

The somatic category includes acute and delayed effects. Acute effects appear within days to
weeks after exposure. Delayed effects may not show up for years after exposure. Acute
radiation syndrome refers to a short-term, whole-body dose. A high dose causes damage to many
vital tissues and organs simultaneously. The results on the human body depend greatly on the
details of the exposure and the individual. Acute radiation syndrome is characterized by four


                                                 12
sequential stages. The initial, or prodromal, stage lasts for the first 48 hours post-exposure. The
individual is likely to exhibit a feeling of tiredness, nausea, loss of appetite (anorexia), and
sweating. The remission of these symptoms marks the beginning of the second, or latent, stage.
The latent stage can last between 48 hours and 2-3 weeks after the exposure. Here the individual
will generally exhibit signs of well being. The third, manifest illness, stage lasts from about 6-8
weeks post-exposure. Symptoms include fever, loss of hair (epilation), lethargy, and perception
difficulties. Hemorrhaging and infection will result from damage to the hematologic system. If
doses were high enough, gastrointestinal distress (e.g. vomiting) will also be present. Provided
the individual survives the third stage, the fourth stage is recovery. This stage may take weeks
to months

An acute, whole-body dose of 450-500 rad of gamma rays would be lethal to about 50% of the
human exposed population, assuming no medical care is administered. In general, this dose is
termed the LD50, or the lethal dose for 50% of an exposed population within a specific
period of time. The term LD50/30, refers to the lethal dose to kill 50% of a population in 30 days.

Latent somatic effects show up many years post-irradiation. Leukemia and other cancers are
examples of delayed somatic effects. Genetic effects are not observed until the next
generation. These genetic mutations are seldom the gross disfiguring types portrayed in horror
movies. In fact, the vast majority of genetically transmitted mutations result in no observable
changes

Laboratory doses of radiation received at the Texas Southern University are not above
background. Acute radiation syndrome is not feasible when working with the Ci and mCi
amounts typical in research laboratories.

4.1 Dose-Effect Models for Response

At least three different dose-effect models are widely presented, although human data fails to
suggest any specific dose-response model is best. The threshold model, the linear response
model, and the linear-quadratic response model all have preferential attributes. Below, Figure 2
illustrates three different radiation doses versus biological effect curves.




                                                13
                         Figure 2: Radiation Dose versus Observed Biological Effect



Linear Response Model
This model assumes that every increase in radiation exposure increases the risk of detrimental
effects. This is the model assumed in radiation protection. Therefore, a small dose of radiation
is assumed to result in a small increased chance of developing a fatal cancer or genetic mutation.
 This model results in the most conservative dose limits.

Linear Quadratic Response Model
This model is described by a quadratic function initially (x2) and then turns more linear at higher
doses. Most radiation-induced solid cancers may be predicted by a linear quadratic function, but
insufficient low-dose data exists to support this model.

Threshold Response Model
This model is based on a threshold value for the dose-injury response, such that below a certain
value there is no risk. Above this threshold, the risk linearly increases with dose. This dose-
effect model represents the observed relationship. At this time, no experimental study has shown
an increased risk for cancer in adults below approximately 15 rem acute, whole-body dose.
Conversely, no evidence exists to conclusively support this model.

4.2 Radiation Protection

Radiation protection guidelines are based on the assumption that there is no threshold for
radiation exposure risk (e.g. linear response model). This is a conservative assumption intended
to protect personnel. Radiation guidelines also assume that the risk of injury linearly increases
with dose. A further conservative simplification used in radiation protection is the lack of
distinction between acute and chronic exposures. This means that dose limits are treated as if
they are received as acute doses, and do not include effects mitigated by cell repair. If a dose is
fractionated over several weeks, the cells have time to repair and recover. Dose fractionation has

                                                 14
a reduced biological effect compared to acute irradiation. Radiation protection standards assume
all doses are acute.

Another important principle used in radiation protection is the ALARA principle. This stands
for "As Low As Reasonably Achievable," which means that exposures should be as low as
possible when considering economic and social factors. The ALARA concept strives to keep
personnel doses low, yet still maintain an effective and productive working environment. This
philosophy dictates sensibility when using radioactive material. Personnel should strive to
reduce unnecessary exposure and optimize any requisite exposures.

4.3 Law of Bergonie & Tribondeau

In 1906, two French radiobiologists, Bergonie and Tribondeau, developed the most widely
used rules for the relative sensitivity of cells to radiation exposure. The most radiosensitive
cells are:

       Cells that have a high division rate,
       Cell that have a long dividing future,
       Cells that are unspecialized.

The first property is determined by the cell's dividing time. The second property refers to cells
that are still in the immature stage of their development, and are dividing rapidly. As cells
mature, they divide less rapidly and function more in their usable capacity. The last property
refers to cells' ability to mature into one of several different mature cell types. An example
would be an immature blood cell that may specialize upon maturity as a lymphocyte or one of
different types of granulocytes. The generalization of this law is that the most radiosensitive
tissues are those that are young and rapidly growing.

Probably, the most radiosensitive human cell is the fertilized ovum. Using the above three
properties, it is easy to see why special consideration is given to radiation exposures of the
fetus. This is discussed in greater detail in Section 5.6 under Prenatal Exposure.

5.0 EXPOSURE LIMITS & PERSONNEL MONITORING

5.1 Personnel Monitoring/Dosimetry

Several methods of personnel monitoring can be used in order to evaluate the amount of ionizing
radiation that a worker has been exposed to. It is important to note that any type of personnel
monitor merely records the amount of exposure received. It in NO WAY protects the wearer
from the radiation and its associated effects.

Personnel dosimetry monitoring is used to assure individuals working in a radiation environment


                                                15
stay below the maximum "legal" exposure limits that can be received within a given period of
time. These limits and guidelines are summarized as follows:

      All work must be conducted in such a manner that no member of the general public could
       receive a dose in excess of 100 mrem in one year.
      All work must be conducted in such a manner that no member of the general public could
       receive a dose in excess of 2 mrem in any one hour.
      All work must also be conducted in a manner such that no individual receives a dose
       exceeding:

       Committed Dose Equivalent (CDE), dose to a particular organ averaged throughout
       each tissue for a 50-year period from an uptake of radioactive material.

       Annual Limit:        Internal- 50 rem (0.5 Sv)

       Committed Effective Dose Equivalent (CEDE), the sum of the committed dose
       equivalents to each organ multiplied by an organ-specific weighting factor.

       Annual Limit:        Internal- 5 rem (0.05 Sv)

       Deep Dose Equivalent (DDE), the dose from external sources measured at a tissue depth
       of 1 cm.

       Annual Limit:        External- 5 rem (0.05 Sv)

       Shallow Dose Equivalent (SDE), the dose from external sources measured at a tissue
       depth of 7mm and averaged over 1 cm2.

       Annual Limit:        External- 50 rem (0.5 Sv)

       Eye Dose Equivalent (EDE), the dose from external sources measured at a tissue depth
       of 0.3 cm.

       Annual Limit:        External- 15 rem (0.15 Sv)

       Total Effective Dose Equivalent (TEDE), the sum of the deep dose equivalent (from
       external exposures) and committed effective dose equivalent (from internal exposures).

       Annual Limit:        Internal + External- 5 rem (0.05 Sv)




                                             16
       Effective Dose Equivalent, the hypothetical uniform whole-body dose, which if
       administered, would result in the same total risk of a fatal cancer or genetic damage. This
       accounts for the fact that energy deposited in one organ is not as damaging as a uniform
       whole-body dose.

       Total Organ Dose Equivalent (TODE), sum of the deep dose equivalent and the highest
       organ-specific committed dose equivalent.

       Annual Limit:               Internal + External- 50 rem (0.5 Sv)

       Fetus Dose Equivalent (Declared Pregnancy), sum of the deep dose equivalent to the
       mother’s lower torso and the highest organ-specific committed dose equivalent.

       Nine-month limit:           Internal + External- 0.5 rem (0.005 Sv)

The Texas Regulations for the Control of Radiation require that personnel monitoring be
performed whenever it is likely that an individual will receive an exposure in excess of 10% of
the applicable annual dose limit.
At Texas Southern University the "typical" or "average" exposures are not above background for
personnel monitoring devices.

Types of Personnel Monitors

Three types of personnel monitors can be used to evaluate radiation exposures.

   Film Badges: These monitor beta, gamma, X-ray exposures. The radiation interacts with the
   photographic-type film in the badge causing a darkening of the film when developed. The
   amount of darkening is proportional to the dose received by the individual. These may be
   used as a whole body, collar, wrist, or general area dosimeters.

   TLD Badges: TLD stands for thermoluminescent dosimeter. The energy deposited by
   radiation is stored in these crystalline-chip badges. This stored energy is released when the
   chip is read. The energy is released in the form of visible light (i.e. luminescence). The
   intensity of light released is directly proportional to the radiation dose to the badge. These
   badges are used to monitor gamma, beta, and X-ray exposures.

   Finger Ring Badges: These smaller TLD badges are worn on the finger to record dose to the
   hands. They are sensitive to gamma, X-ray, and high-energy beta exposures (see Section 5.3
   on Criteria for Requiring Extremity Monitoring).




                                               17
5.2 General Rules for Use of Personnel Monitors

Some basic guidelines must be followed in order to accurately evaluate personnel exposures:

      Always wear your own personnel monitor. Never allow another person to wear your
       badge and never wear a badge assigned to another individual.

      When issued a new film dosimeter, make sure that your name appears through the
       window in the front. Any other orientation will cause an erroneous dose assessment.

      Badges are designed to monitor exposures for the wearing period beginning with the date
       shown on the badge. All badges must be returned to the Radiation Company that issued
       them at the end of each wearing cycle promptly, even if not worn during that period.

      Never wear your badge when undergoing any type of medical or dental radiographic
       procedure as a patient. Badges are intended to measure doses received while performing
       your job duties.

      In the event that your badge is lost, damaged, notify the Radiation Company that issued
       the badge to arrange for a replacement. Work with radiation (if the badge is required)
       should NOT take place until the personnel monitor is replaced.

      Remember that these devices do not act as warning devices when an individual receives a
       radiation exposure. They do not change color, beep, or in any other way visually indicate
       that exposure has been received. Their sole function is to legally document the radiation
       dose an individual may receive from working with radioactive material.

5.3 Prenatal Radiation Exposure

Since the Law of Bergonie and Tribondeau was published in 1906, it has been known that cells
are more sensitive to radiation damage when they rapidly divide and are relatively unspecialized
in their function. Therefore, children are more sensitive to radiation than adults, and the unborn
are even more sensitive, especially during the first trimester.

This principle of increased sensitivity has long been a factor in the development of radiation dose
limits. Because the risk of harmful effects from radiation may be greater for young people, dose
limits for minors are lower than for adult workers. Specifically, this limits anyone under 18
years of age to exposures not exceeding one-tenth of the limits for adult workers, (i.e. 500
mrem annually).

When a woman is pregnant and her abdomen is exposed to radiation, the sensitive fetus is also
exposed. A number of scientific studies have shown that the unborn are more sensitive than the


                                                18
adult is, particularly during the first three months after conception. During a significant portion
of these critical three months, a woman may not know that she is pregnant. Because of these
factors, the National Council on Radiation Protection and Measurements (NCRP) recommends
that special precautions be taken to limit exposure when an occupationally exposed woman
might be pregnant. Another agency, the International Commission on Radiological Protection
(ICRP) also recommends limiting exposure of the unborn during pregnancy.

Both the NCRP and the ICRP have recommended that, during the entire pregnancy, the
maximum permissible dose equivalent to the unborn from occupational exposure of the
expectant mother should not exceed 500 mrem.

Prenatal Radiation Exposure as Compared to Other Risk

Many common activities have been shown to be harmful during pregnancy. It is helpful to view
the risk associated with radiation exposure by comparing it to the risks associated with these
other activities. For instance, cigarette smoking during pregnancy can cause reduced birth weight
and infant death. Alcohol consumption during pregnancy can cause growth deficiencies, brain
dysfunction, and facial abnormalities. A radiation exposure of 1000 mrem may cause childhood
cancers. On page 18-19, Table 1 compares prenatal radiation exposure with other activities and
the potential risks for negative outcomes.




                                                19
     Table 1: Comparison of negative outcomes from various prenatal exposures.


        FACTOR                PREGNANCY OUTCOME                   RATE OF
                                                                OCCURRENCE

German Measles               Birth Defects                            2 in 3
Cigarette Smoking

       <1 Pack/day           In general, babies weigh 5-9             1 in 5
                             ounces less than average
       >1 Pack/day           Infant Death                             1 in 3
Alcohol Consumption

       2 drinks/day          Babies weigh 2-6 ounces less             1 in 10
                             than average
      2-4 drinks/day         Fetal Alcohol Syndrome                   1 in 5
       >4 drinks/day         Growth Deficiency, Brain             1 in 3 to 1 in 2
                             Dysfunction, Facial Signs
Maternal Age

         20 Years            Down's Syndrome                        1 in 2300
       35-39 Years           Down's Syndrome                          1 in 74

       40-44 Years           Down's Syndrome                          1 in 39
Radiation exposure
1000 mrem

     Childhood cancer        Death before age 12                    1 in 3333
Death form other childhood   Death before age 10                    1 in 3571
  cancers before age 10
Bomb exposure at 4-14
weeks gestation

  Hiroshima (15-100 rads)                                             1 in 4
   Nagasaki (>150 rads)                                               1 in 4



                                             20
It is the responsibility of the mother to decide whether the risks to a known or potential unborn
child are acceptable. The Nuclear Regulatory Commission recommends that the mother consider
the following facts:

      The first 3 months of pregnancy are the most important, so the decision to avoid risk
       should be made early.

      In most work situations, the actual dose received by an unborn child would be less than
       the dose to the mother, because the mother absorbs some of the dose.

      The dose to the unborn child can be reduced by (1) reducing the amount of time exposed
       to the source of radiation, (2) increasing the distance of the mother from the source of
       radiation, and (3) shielding the abdominal area.

      If a woman becomes pregnant, she can ask her employer to reassign her to areas involving
       less exposure to radiation.

      When occupational exposures are kept below the regulatory limit of 5000 mrem per year,
       the risk to the unborn child is thought to be small. By following the NCRP
       recommendation of 500 mrem for the entire pregnancy period, it is presumed this risk is
       decreased. Experts disagree on the exact amount of risk these actions eliminate.

The Decision of the Mother

Any female radiation worker who knows, suspects, or may become pregnant is encouraged to
contact the Radiation Safety Officer as soon as possible to obtain information on the risks of
radiation with pregnancy. A confidential meeting will be scheduled between radiation safety
personnel and the woman.

It is up to the mother to compare the benefits of her employment against the possible risks
involving occupational radiation exposure to a known or potential unborn child. The mother
should know what the Pregnancy Discrimination Act states. An amendment of Title VII of the
Civil Rights Act of 1964, states "women affected by pregnancy, childbirth, or related medical
conditions shall be treated the same for all employment related purposes, including the receipt of
benefits under the fringe benefits programs, as other persons not so affected but similar in their
ability or inability to work." In addition, the Equal Employment Opportunity Commission is
responsible for examining cases for compliance with this act.




                                               21
6.0 LABORATORY PROCEDURES

6.1 Postings and Labels

Areas where radiation sources are utilized or stored must be posted with a caution radioactive
material sign informing others of the potential hazard. Typical areas posted include the doors
leading into the facility, the designated radionuclide work and storage areas, and waste
containers. Legal requirements have been established which govern the verbiage, shape, and
color on radiation postings. The Radiation Safety Officer or Radiation Committee Chair should
be contacted for assistance with the selection and placement of any radiation-related warning
sign.

6.2 Receipt and Inventory of Radioactive Material

All radioactive materials purchased must receive prior approval before ordering from the
Radiation Safety Officer or Radiation Committee Chair. This approval is independent and in
addition to other purchasing requirements. Properly completed paperwork will allow for prompt
processing and distribution of the package.

Laboratory personnel must maintain the radioactive material use log. An example is shown on
the following page. The heading information uniquely describes each primary vial, including
radionuclide, activity received, and Ship Code. As the isotope is used in the laboratory protocol,
the date, activity used, radioactive waste form (e.g. liquid, solid, or vial), and signature must be
recorded on the Radionuclide Inventory Form.

6.3 Approval for Orders of Radioactive Material

The Radiation Safety Officer or Radiation Safety Committee Chair must approve all radioactive
material acquisitions (purchases). An Authorized User must notify the Radiation Safety Office
before submitting an order for radioactive materials to the Purchasing Department. Radiation
Material Request Form (RADMAT) can be downloaded from TSU website. This form is a
quick and easy way to notify the Radiation Safety Office of your intent to order or receive
radioactive materials.
6.4 General Radiation Safety Guidelines

Irradiation occurs in two specific ways, externally from radioactive material or other radiation
sources outside the body, or internally from radioactive material deposited in the body.

External exposures can be the result of exposure to gamma, x-ray, or high-energy beta-particle
emitters. Low-energy beta and alpha particles lack the energy needed to penetrate the outer
protective layer of skin. Subsequently, these radionuclides present more of an internal exposure
hazard. The amount of exposure an individual receives depends on the following factors:


                                                22
   Activity: The "strength" of the radiation source. When the activity of radioactive material is
   reduced or the settings on a radiation producing machine are lowered, the potential radiation
   dose is reduced.

   Time: The total dose received from an external source is also dependent on the amount of
   time exposed to the source. Therefore, time spent near a radiation-producing source should
   be optimized.

   Distance: By increasing the distance between the radiation source and the individual, the
   dose received can be significantly reduced. If an individual doubles the distance from a point
   source, the dose rate will drop to 1/4.

   Shielding: When high-activity radiation sources are being used, absorbing material, or
   shields, can be incorporated to reduce exposure levels. The specific shielding material and
   thickness is dependent on the amount and type of radiation involved.

Internal dose results from the intake of radioactive materials. This material may be incorporated
into the body in several ways.

          Inhaling radioactive vapors, fumes, or dust.

          Consuming radioactive material located on contaminated hands, tobacco products,
           food, or water.

          Entering through a wound.

          Absorption through the skin.

The fundamental objectives of radiation protection are:

      To reduce exposure to external radiation to as low a level that is reasonably achievable
       and always below the established radiation dose limits.

      To avoid entry of radionuclides into the human body via ingestion, inhalation, absorption,
       or through open wounds when radioactive material is handled.

An important secondary objective is to obtain reliable results from experiments and clinical
procedures. To accomplish these objectives, positive planning and following of procedures
beyond the usual care taken in work with other materials is required. To accomplish this it is
necessary to (1) analyze in advance the hazards of each job, (2) provide safeguards against
foreseeable accidents, and (3) use protective devices and planned emergency procedures for

                                               23
accidents that do occur.

General Radiation Safety Guidelines for the Use of Radiation Sources

      Before starting work with any source of radiation, a full understanding should be reached
       between all laboratory and clinical personnel as to the work to be done and the necessary
       safety precautions.

      The procedure for each project should be outlined in writing for all laboratory personnel.
       Necessary equipment, shielding, waste containers, and survey instruments must be
       available.

      Characteristics of the radioactive material such as type of radiation, half-life, typical
       activities, detection means, waste disposal means, and chemical form should be known.

      In some cases, before the procedure is actually performed with radioactive material, a
       "dry run" of the procedure may be needed so as to avoid any problems.

      A radiation worker knowledgeable of the operation should supervise visitors and students
       in a laboratory that uses radiation sources. No visitor or student shall be permitted to
       work with radiation sources without first being trained by the authorized licensee.
      Sources of radioactivity must not be left unattended in places where they may be handled
       or removed by unknowing or unauthorized persons.

      As a general practice, work with radioactive material should be confined to only the areas
       necessary. This simplifies the problem of confinement and shielding and aids in limiting
       the affected area in case of an accident.

      All work surfaces and storage areas (e.g. tabletops, hoods, and floors) should be covered
       with absorbent material to contain liquid radioactive material spills. Some facilities pose
       a significant decontamination problem, due to porous work surfaces.

      Absorbent mats or paper should be used. Protective absorbent with a plastic backing and
       paper front is especially useful. If contaminated, it can simply be discarded in the solid
       radioactive waste container.

      When using radioactive liquids, plastic or metal trays (stainless steel washes easily)
       should be utilized to contain potential spills. The lip of the tray confines liquid
       radioactive materials.

      Good housekeeping should be practiced. If an area is kept neat, clean, and free from
       equipment not required for the immediate procedure, then the likelihood of accidental

                                               24
    contamination or exposure is reduced.

   Radioactive material, especially liquids, should be kept in unbreakable containers
    whenever possible. If glass is used, a secondary container is necessary.

   Never pipette by mouth! Always use some type of pipette filling device.

   Eating, drinking, applying cosmetics, or storing food is prohibited in areas where work
    with unsealed radioactive sources is taking place due to potential contamination.

   Refrigerators in laboratories with radioactive material shall not be used for the storage of
    food or drinks.

   Smoking is not permitted in areas where work with unsealed radioactive sources is in
    progress or where contamination may exist. Under no circumstances should cigarettes,
    cigars, or pipes be laid on tables or benches where radioactive work has been performed
    or is in progress.

   Before eating, drinking, applying cosmetics, or smoking, personnel performing
    radioactive material work should wash their hands and forearms thoroughly.

   Gloves must be worn any time an unsealed source is being used, or whenever
    contamination is likely. To prevent cross-contamination, do not use the phone, handle
    books, open cabinets, or anything else with contaminated gloves. If there is a lesion on
    the hand, gloves will help prevent internal absorption of radioactive material.

   All individuals using radioactive material should wear laboratory coats, long pants, and
    closed-toe footwear.

   All reusable glassware and tools used with radioactive material should be thoroughly
    cleaned after use and kept separate from non-contaminated items. It is recommended that
    a marked container or area be provided for glassware and tools used in radioactive work.

   Wear your personnel radiation monitoring device(s).

   Determine potential radioactive material contamination by surveying with an appropriate
    radiation detector. If readings are unusually high, then find out why and correct the
    problem or call the Radiation Safety Division.

   Discard radioactive waste in containers provided.




                                            25
General Radiation Safety Guidelines for the Use of Radiation Producing Electronic Equipment

      Each individual intending to operate any radiation-producing machine should be properly
       trained by an individual familiar with the equipment.

      Each individual working with radiation producing electronic equipment should know
       exactly what work is to be done and which applicable safety precautions should be used.

      Written operating and safety procedures should be available to personnel before
       operating the equipment.

      The equipment operator should supervise visitors and students in the area of work.

      Radiation producing machines should not be left unattended in an operational mode.

      Structural shielding requirements for any new installation or any modifications to an
       existing unit or room should be reviewed by a qualified expert before the machine is
       used.

      When the safe use of the equipment depends on the mechanical set up of the unit or on
       technique factors, these restrictions should be rigidly followed.

      Under no circumstances should any shutter mechanism or interlock be defeated or in any
       way modified.

      All warning lights should be of the "fail safe" type.

      A cumulative timing device that can be manually reset should be used to indicate elapsed
       exposure time and to turn off the machine when the total exposure reaches the planned
       amount.

      Proper maintenance on all radiation producing equipment is essential. ONLY properly
       trained technical personnel should perform all repairs to the equipment.

6.5 Radiological Health Surveys

It is necessary to perform radiological health surveys whenever radiation sources are used to
verify the efficacy of the protection practices. Surveys must be designed for the specific
radiation sources in the laboratory. Laboratory directors are responsible for performing routine
lab surveys. In addition Radiation Safety Committee Chair or Radiation Safety Officer will

                                                26
perform periodic inspection of laboratories assuring that they comply with the regulations and
keep proper records.

Routine monitoring of laboratories containing radioactive material is necessary for the protection
of radiation workers, compliance with regulations, and prevention of radioactive material
contamination.

Laboratories working intermittently with radiation sources may be removed from the routine
survey schedule providing a survey is performed and documented after the last use of radioactive
material.

Corrective Actions for Violations

Any radiation safety violations observed during a routine survey are documented, and steps are
initiated to correct the issue. The procedure usually involves verbal notification, followed by
written warnings if the problem is not addressed after verbal notification. In extreme
circumstances, action by the Radiation Safety Committee may be utilized.

Any operation causing an excessive radiation hazard will be suspended immediately by the
Radiation Safety Officer without regard to the above procedure. The Radiation Safety
Committee will also promptly review any such actions.

In addition to the routine surveys performed by the Radiation Safety Committee Chair, each
laboratory is responsible for performing their own work-area contamination surveys. A
documented survey should be maintained for each month that radioactive material is in use for
each room where radioactive material is in use. The Basic Radiation Safety Course offered by
the Radiation Safety Committee will instruct workers how to properly survey for radioactive
material and interpret the results.

6.6 Waste Disposal

All radioactive wastes must be disposed in manner appropriate with the regulations. Each lab
director is responsible for securing the commercial company for the disposal of radioactive
wastes. The University does not have a centralized system for storage and disposal of the
radioactive wastes. However, any disposal of materials, wastes, animals, or scintillation vials
containing radioactive material in any other manner may result in the loss of permission to use
radioactive material at Texas Southern University.

Different types and forms of radioactive waste warrant different methods of disposal. As an
example, LS vials containing 3H are disposed of differently than solid wastes containing 32P. For
this reason, each laboratory should have waste containers for each specific type of waste
generated. The general classifications for each type of waste generated are: Solid Waste, Liquid
Scintillation Vials, Biological Waste, Liquid Waste, and Special Waste.

                                               27
Solid Waste

Solid Waste is segregated and classified into the following categories :

Solid Waste ( Half-life > 300 days) ex: 3H ;14C
Solid Waste ( Half-life < 300 days) ex: 32P; 35S; 125I

The solid waste is segregated and placed in containers lined with thick opaque plastic bags at the
point of generation. Containers and bags are responsibility of each laboratory. When the bag is
filled to 2/3, it is sealed, tagged with a Radioactive Waste Disposal tag, and should be disposed
through arrangement with a commercial company

Liquid Scintillation Vials

Liquid Scintillation vials are classified and segregated in accordance with the following
guidelines:

Liquid Scintillation Vial Waste (3H, 14C, 125I<0.05 Ci/ml)
Liquid Scintillation Vial Waste (32P; 35S; all other isotopes)

The liquid scintillation vials are placed in containers lined with thick opaque plastic bags at the
point of generation. Containers and bags are responsibility of each laboratory. When the bag
filled to 2/3, it is sealed, tagged with a Radioactive Waste, Disposal and should de disposed
through arrangement with a commercial company. Only biodegradable or environmentally safe
liquid scintillation cocktails are accepted for disposal by the Radiation Safety Committee.

Biological Waste

Biological waste that also contains radioactive material should be placed in thick opaque plastic
bags and placed in freezers until picked up by the commercial company Each bag must have
accompanying it a completed Radioactive Waste Disposal Tag.

Infectious biological waste should not be disposed of until special precautions and warnings have
been considered. Biological Waste is segregated in accordance with the following guidelines:

Biological Waste ( Half Life > 300 days)
Biological Waste ( Half Life < 300 days)

Biological waste containing 3H,    14
                                     C, and   125
                                                    I with concentrations less than 0.05 Ci/gm can be


                                                      28
disposed of as non-radioactive.

Liquid Waste
Liquid radioactive waste is separated by radionuclide and placed in the proper one-gallon
containers. They are responsibility of the laboratory. Only liquid waste may be placed in the
container. Emulsified tissue, feces, or biological waste that will support microbiological growth
at room temperature shall not be placed in the liquid container. When washing containers that
were used with radioactive materials, the first and second rinse is usually retained as liquid
radioactive waste. Any subsequent rinses may be allowed to go down the drain, as long as it is a
designated radioactive waste sink.

When filled, a Radioactive Waste Disposal tag is completed and affixed to the container. These
tags must include information such as radionuclide, activity, and user information. It is the
responsibility of the laboratory to arrange the disposal of the wastes through a commercial
company.

Each laboratory should designate an area for the location of their radioactive waste containers.
When choosing this area, several items should be kept in mind.

      The area should be obviously labeled so that the waste in this area is not inadvertently
       discarded as normal trash.
      Consider shielding requirements for the radioactive waste container.
      Adequate spill and leakage protection should be provided, such as absorbent paper and
       spill trays.

6.7 Instrumentation

A few basic types of radiation detection instruments are commonly used at Texas Southern
University. The Geiger-Mueller (GM) survey meter, NaI scintillation detector, and liquid
scintillation counter are commonly used for radiation contamination measurements. Many
different types of detectors and meters are available; however, these detectors are the most
common for general-purpose lab surveys and wipe tests.

The Geiger-Mueller Survey Meter

The GM survey meter can detect beta particles and gamma rays effectively. The meter measures
the number of radiation interactions per unit time, usually in counts per minute (cpm). This
number is proportional to the number of disintegrations per minute of the sample. The
disintegrations per minute (dpm) is equal to the counts per minute (cpm) divided by the
efficiency of the meter (eff). The efficiency of the detector depends on the energy of the
radionuclide (e.g. 32P or 3H) and the geometry of the source (e.g. point source or disk source).



                                               29
                                            dpm = cpm/eff


Geiger-Mueller survey meters often have a mR/hr scale. There are significant inaccuracies
involved with this scale, but it should give a reasonable approximation for the energies of
interest. A GM survey meter with a pancake probe is an appropriate surface contamination
detector. This type of meter will not reliably detect 14C or 3H, since the low-energy beta particles
cannot penetrate the detector window.

The Scintillation Counter

This type of meter is appropriate for gamma-emitting radionuclides. The scintillation detector is
more sensitive than a GM detector for gamma rays although the cost is usually higher. This
detector is not efficient for beta-emitting radionuclides. Efficiency corrections must also be
made to convert cpm to dpm.

The Liquid Scintillation Counter

The liquid scintillation counter (LSC) is the most sensitive of the three detectors. The LSC can
be used to measure alpha particles, beta particles, and gamma rays. The LSC provides the most
effective means of determining removable radioactive material contamination. The LSC is the
preferred detector for 3H, 14C, and 35S. The liquid scintillation counter in the Radiation Safety
Lab is available to UTHSC employees.

7.0 EMERGENCIES

Emergencies involving radiation should be treated as any other emergency with respect to bodily
injuries, fires, and explosions. Any radiation exposures and contamination will be addressed
after the physical hazards are contained. DO NOT PANIC.

7.1 Emergency Response
    In Case of a Radiation Spill:
    1. Notify all personnel in the area that a spill has occurred.

   2. Cover the spill with absorbent paper to prevent spread.

   3. Wearing disposable gloves, remove the contaminated absorbent paper, and place it in a
      plastic bag. Carefully remove the gloves and place them in the plastic bag. Place the bag
      in an appropriate radioactive waste container.

   4. Take wipe tests and use a survey meter to determine the extent of the contamination. If
      contamination is still present, clean the area with an appropriate solvent using the clean
      hand/dirty hand method.

                                                 30
   5. Notify Radiation Safety Officer or Radiation Safety Committee Chair of the event:
       313-1896, 313-7990. If you have any concerns regarding contamination please contact
      the Radiation Safety Officer or Radiation Safety Committee Chair.


8.0 RULES REGULATIONS, RIGHTS, AND RESPONSIBILITIES

The Texas Department of Health has established standards for your protection against radiation
hazards, pursuant to the Texas Radiation Control Act, Art. 4590f, Revised Civil Statutes, State of
Texas.

8.1 Texas Southern University’s Responsibility

Texas Southern University is required to:
   1. Apply the safety regulations to work involving sources of radiation.
   2. Post or otherwise make available to you a copy of the Texas Department of Health
       regulations, licenses, certificates of registration, notices of violations, and operating
       procedures which apply to work you are engaged in, and explain their provisions to you.

8.2 Employee’s Responsibility

You should familiarize yourself with those provisions of the regulations and the operating
procedures that apply to the work you are engaged in. You should observe the provisions for
your own protection and protection of your co-workers.

8.3 What is Included in these Regulations

   1.   Limits on exposure to radioactive material in restricted and unrestricted areas.
   2.   Measures to be taken after accidental exposure.
   3.   Personnel monitoring, surveys, and equipment.
   4.   Caution signs, labels, and safety interlock equipment.
   5.   Exposure records and reports.
   6.   Options for workers regarding inspections by the Agency.
   7.   Related matters.

8.4 Reports on Your Radiation Exposure History

   1. The regulations require that your PI gives you a written report if you receive an exposure
      in excess of any applicable limit as set forth in the regulations or in the license. The basic
      limits for exposure to employees are set forth in Title 25 of the Texas Administration
      Code under Section 289.202. These sections specify limits of exposure to radiation and
      exposure to concentrations of radioactive material in air and water.

                                                 31
   2. If you work where personnel monitoring is required:

       (a) Upon termination of your employment, your employer must give you a written report
           of your radiation dose if that dose exceeded 10% of any limit set forth in 25 TAC
           §289.202, and

       (b) Upon written request, your employer must advise you annually, or upon termination
           of association, of your exposure to radiation regardless of the amount of exposure.

8.5 Inspections by the Texas Department of Health

All licensed or registered activities are subject to inspection by representatives of the Texas
Department of Health. Each PI is required to maintain lab and personnel records, that is records
of ordering, receiving, use and disposal of radioactive materials and wastes, records of wipe tests,
records of monitoring devices (if used), records of calibration of detection devices, and spill
cleanups if such occurred, etc., in the lab readily available for inspection. If any of these are not
fulfilled it will be deemed as a radiation safety violation requiring corrective measures as
stipulated by the Texas Department of Health.
In addition, any worker or representative of workers who believes that there is a violation of the
Texas Radiation Control Act, the regulations issued thereunder, or the terms of the employer's
license or registration with regard to radiological working conditions in which the worker is
engaged, may request an inspection by sending a notice of the alleged violation to the Texas
Department of Health. The request must set forth the specific grounds for the notice, and must be
signed by the worker as the representative of the workers. Also, any worker may bring to the
attention of the inspectors any past or present condition that they believe contributed to or caused
any violation as described above.




                                                 32

				
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