Radiation Safety Manual


The rules and regulations that govern the use of radiation and radioactive material on the University of Northern Iowa campus are contained in the State of Iowa Rules and Regulations on Radioactive Material, Chapter 641.38-45, and enforced by the Iowa Department of Public Health (IDPH).

This Radiation Safety Manual was prepared as a guide in administering the IDPH rules and regulations at the University of Northern Iowa.  It provides specific requirements that Authorized Users will adhere to.  This manual also defines the level of compliance required of individuals who wish to utilize radioactive materials or radiation-producing machines while working at the University of Northern Iowa.

The extent to which radiation safety is practiced in the laboratory depends not only on the quality of the safety related information provided, but also on the willingness of the Authorized Users to model safe practices in the laboratory.  It is incumbent on every Authorized User to familiarize themselves with the contents of this manual and to follow the procedures and requirements that pertain to their specific research or teaching program.

The requirements of this Radiation Safety Manual have the authorization of the Vice President for Administration and Finance, the University’s Authorized Representative.  The University Safety Officer is authorized to provide oversight to the Environmental Health and Safety Office.  Knowledge of and adherence to these procedures is the responsibility of every individual who utilizes radioactive materials and radiation producing devices.  All users shall cooperate with the Radiation Safety Committee and the Radiation Safety Officer, who have administrative responsibilities for the radiation safety program and related issues on the University of Northern Iowa campus.



As the use of radiation emitting materials and devices has grown, so has our understanding of the potential hazards associated with their use.  Concerns over the potential hazards and associated risks have led to recommendations governing the exposure limits and ultimately to strict regulatory controls governing the possession and use of all sources of ionizing radiation.

Current limits for radiation exposure are based on the conservative assumption that there is no completely safe level of exposure.  Under this assumption, even the smallest exposure has some probability of causing a latent effect such as genetic damage or cancer.  This assumption results in the philosophy and regulatory requirement that exposure limits be kept “As Low As is Reasonably Achievable (ALARA).

This manual contains the information and procedures that must be understood and followed in order to ensure that all uses of ionizing radiation at the University of Northern Iowa are in compliance with existing regulatory requirements and that any resultant radiation exposures are maintained ALARA.

Radiation Materials License

Possession and use of radioactive materials in the United States is governed by strict regulatory controls.  The primary regulatory authority for most types and uses of radioactive materials is the Federal Nuclear Regulatory Commission (NRC).  More than half of the states however have entered into “agreement” with the NRC to assume control of radioactive material within their boundaries.  Iowa is an “agreement state” and has given authority to the Iowa Department of Public Health (IDPH) for regulatory compliance oversight.

A license to possess and use radioactive material has been issued to the University of Northern Iowa by the IDPH.  It is a class “C” restricted use license with the number 00329-1-07-RD2.  As such, it requires UNI to maintain a well-managed and documented radiation protection program to ensure that radioactive materials are used safely. The license contains the information you need to use radioactive material in accordance with UNI policies and Iowa Department of Public Health regulations. Copies of the license and the Iowa Radiation Control Regulations are available for review and inspection at the Environmental Health and Safety Office.

Under the terms of the license, Authorized Users are certified by the Iowa Department of Public Health and fall under the local authority of the Radiation Safety Officer.

Radiation Safety Committee

A Radiation Safety Committee (RSC) has been established at the University of Northern Iowa.  The RSC is responsible for ensuring that radioactive materials and radiation-producing devices are used safely and in accordance with state and federal regulations as well as institute policies.


The Radiation Safety Committee will be composed of authorized users and technical personnel who work with radioactive materials or X-ray producing devices, including a representative of Management and a representative from each college or department that used ionizing radiation.  The Radiation Safety Officer will be an ex-officio member of the RSC.

Members of the committee will consist of Authorized Users and technical personnel who work with radioactive materials or X-ray producing devices.
A quorum will consist of a simple majority of RSC members and the RSO or their proxies.


  • The RSC will meet annually and more often when situations arise that need attention.
  • The RSC will review and approve all proposed experiments and tests utilizing radioactive material in excess of exempt quantities and exempt concentrations, and all other types of ionizing radiation on the UNI campus.
  • The RSC will review and approve proposed radioactive materials and radiation producing equipment operating procedures for the UNI campus.  It will also review and approve revisions to already existing procedures.  Minor modifications to procedures and supporting forms which do not change the original intent of the procedure may be approved by the Radiation Safety Officer.  Individuals on the RSC will serve as technical content experts providing consultation to the RSO.
  • The RSC will review reportable occurrences and take appropriate action.
  • The RSC will review and approve proposed changes to the ionizing radiation facilities (i.e. shielding, ventilation) pursuant to the Iowa Department of Public Health rules and regulations.
  • The RSC will audit, on a biennial and annual basis, the radiation safety program for adequacy and operational records for compliance with internal rules, procedures, regulations and license conditions.  The audit results will be sent to the University Safety Officer.
  • The RSC will audit radiation safety equipment performance with particular attention to operating anomalies, reportable occurrences, and the steps taken to identify and correct deficiencies on an annual basis.  The audit results will be sent to the University Safety Officer.
  • Minutes of the RSC meetings, including any recommendations or occurrences, shall be recorded and distributed to all committee members and the University Safety Officer.  Committee minutes will also be on file in the RSO office and posted on the web.
  • The RSC shall review and certify all applications for the use of ionizing radiation on the UNI campus including radioactive materials and radiation generating devices prior to sending to IDPH.

Radiation Safety Officer

The Radiation Safety Officer (RSO) works for the University Environmental Health and Safety Office.  The RSO is qualified to advise others on safety matters pertaining to ionizing radiation due to their level of education, training and experience.  The RSO shall supervise and administer the radiation safety program at the University of Northern Iowa.


  • The RSO shall act in a supervisory/administrative capacity in all aspects of the UNI radiation safety program including maintenance of records, survey methods, waste disposal, and radiological safety practices.
  • The RSO will review and recommend all activities and procedures that involve actual or potential exposure of personnel to radiation or the release of radioactive materials to the environment.
  • The RSO will be available to consult with all users of ionizing radiation so as to provide advice on radiological safety matters.
  • The RSO will maintain an inventory of all radioactive material sources and radiation producing equipment on the UNI campus.
  • The RSO will implement a radiation survey program for the UNI campus as deemed appropriate in the interest of radiation safety.  Appropriateness in this instance will be based on adherence to and compliance with Iowa Department of Public Health regulatory requirements.
  • The RSO will maintain records of radiation surveys and exposures of personnel to ionizing radiation as may be required to demonstrate compliance with state and federal regulations and other industry good practices.
  • The RSO will serve as a resource to Authorized Users in the training of users of radionuclides and ionizing radiation producing machines.  Annual training will be provided to Authorized Users to keep current with regulations and institutional policies.


  • The RSO has the authority and responsibility to interrupt or suspend any activity that involves the use of radiation if the methods and/or procedures used in such experiments in their professional opinion are deemed to be unsafe and/or contrary to regulations.  This includes laboratory shut down or confiscation of materials. The interruption/suspension will remain in effect until resolved.
  • The RSO has the authority and responsibility to review and approve proposed experiments and tests utilizing exempt quantities and exempt concentrations of radioactive materials.
  • The RSO has the authority and responsibility to review and approve minor changes in the Authorized User Form A approvals (i.e. room changes, minor changes in procedure provided the change does not diminish radiation safety).​An Authorized User (AU) is a UNI faculty or staff person who obtains written authorization from the RSO, following the initial RSC certification and approval from the Iowa Department of Public Health, to use radioactive material and/or radiation producing equipment in research, educational and service activities at UNI.

Authorized User

An Authorized User (AU) is a UNI faculty or staff person who obtains written authorization from the RSO, following the initial RSC certification and approval from the Iowa Department of Public Health, to use radioactive material and/or radiation producing equipment in research, educational and service activities at UNI.


  • The AU is responsible for using radioactive materials in accordance with written procedures that conform to state, federal and institutional rules and regulations.
  • The AU is responsible for providing specific laboratory training and familiarity with the Radiation Safety Manual to individuals working under their direct supervision to ensure the individual’s personal safety.  
  • The AU assumes liabilities for any person under their supervision.
  • The AU will maintain up-to-date inventory of the radioactive materials and radiation producing equipment for which they are responsible as well as other mandatory records (i.e. After Use Survey, Receipt of Radioactive Materials Wipe Test Survey, and Drain Disposal).
  • The AU is responsible to notify the RSO in advance of any changes in the storage or use of radioactive materials or radiation-producing devices.  In the case of any damage, fire, or theft of radioactive materials, the AU is responsible to notify the RSO immediately. 
  • The AU is responsible for preparation and holding of radioactive waste material designated for disposal.   While in the laboratory, radioactive waste materials will be stored in appropriate containers.  The AU is also responsible for providing the appropriate paperwork regarding radioactive waste material to the RSO at the time of waste transfer to the Waste Storage Room.
  • The AU is responsible for posting appropriate radiation signs and labeling containers of radioactive materials with the standard radiation warning symbol in their laboratory area where the material is used.
  • The AU will post in the laboratory area, IDPH required postings, UNI Radiation Safety rules and emergency procedures, and other notification directions as deemed necessary to assist individuals in responding appropriately to spills and other emergencies.  
  • The AU is responsible to continually evaluate their use of radiation to determine if it is possible to further reduce exposure to individuals (ALARA).


Application for Possession and Use

Faculty members who wish to acquire and use radioactive materials must submit an Application for Possession and Use of Radioactive Materials form to the Radiation Safety Committee (RSC) via the Radiation Safety Officer (RSO). A personal statement of training and experience for use of radioactive material must accompany the application form for a new Authorized User (AU). Once the RSC reviews and certifies the application materials, the application materials will be forwarded to IDPH who ultimately grants AU approval. 

Each application must be completed in sufficient detail for the RSC evaluation:

  • Applications must include the name of the Authorized User, the radionuclide, the chemical or physical forms, the amount for use per experiment and the maximum daily order limits.
  • An experiment protocol must accompany each application, describing precautions to avoid the inadvertent release or ingestion/inhalation of radioactive material.
  • Name any hazardous chemicals and compounds in addition to the radionuclide that will be used in the experiment.
  • The RSC may require additional information such as facility design, type of radiation detection equipment, emergency procedures, waste disposal methods, and any relevant training and experience of personnel.

Application for Amendment to Possession and Use of Radioactive Materials

A request for amendment to an approved application is submitted as above on the form Request for Amendment to Application for Possession and Use of Radioactive Materials available from the Safety Office.  Amendment requests may be made only for the following changes:

  • Chemical/physical form
  • Daily order limit
  • Location of use
  • Use procedure
  • Any changes other than those listed above require submission of a new Application for Possession and Use of Radioactive Materials form. 

Radioactive Material Use Permit Termination and Non-Compliance Policy

Any user found to be in violation of the policies and procedures set forth by the University Radiation Safety Manual is subject to having their radiation usage privileges suspended until corrective action is taken.  If the user fails to show that corrective action has been taken or have willfully endangered the health of the university community, they will be immediately be removed from the University Radiation Producing Machine Permit and/or the Radiation Materials License.


Radioactive material may be brought onto campus only with the prior approval of the Radiation Safety Officer or the University Safety Officer.  The steps for obtaining radioactive material are outlined below:

Ordering and Receipt

The Authorized User (AU) must request permission from the RSO to order the desired material by completing the Nuclide Pre-Approval Form.

Nuclide Pre-Approval Form

The RSO will verify that the AU is authorized for the material and that the amount ordered will not put the AU over their possession limit. The RSO will provide the AU with written permission to order the material.

The AU will then order the material and provide the vendor with a copy of the RSO’s written permission.  The AU will have the vendor deliver the material to the EH & S house on University Avenue, House #26, Cedar Falls, IA  50614-0197.

The RSO will perform the required receipt surveys and deliver the package to the AU. The RSO will update the AU’s inventory and the total University inventory.

Transfer or Shipment of Radioactive Material

Any proposed transfer or radioactive materials between individuals on campus must be approved by the RSO.  Off campus transfers are not allowed. 

Prior approval by the RSO is required before transfers have taken place.

On-campus Transfers

Approval of a transfer or radioactive materials between individuals on the UNI campus will depend primarily upon whether the individual who wishes to receive the material has been authorized by the Iowa Department of Public Health for the type and quantity of radioactive material involved and for the specific procedures in which it will be used.  If the receiving person is not authorized to use radioactive materials, then the proper steps towards placement onto the license must be taken for this person.  Only after the IDPH has approved this person will the transfer take place.

Once the transfer has taken place, the new location of the material must be documented by the new user, previous user, and the RSO.

Off-campus Transfers

Under no circumstances will off-campus transfers be allowed.  All radioactive materials are strictly for on-campus use by the Authorized User licensed for the specific material.  This includes any individual working under the AU.

Radioactive Materials Training Program

Authorized User (AU)

Training will be required for all AUs who are working with radioactive materials at UNI, on an annual basis for a refresher, or when a significant change in the duties, regulations or terms of the license occur.  New AUs will be required to take training before starting work with radioactive materials. The training is available on the UNI Safety Website (https://risk.uni.edu/radiation-safety).  The training involves viewing a power point presentation, watching a video, and taking a quiz.  The quiz will be maintained in the AU file to serve as a record of the training.  

Support Staff

Any worker whose duties may require them to work in the vicinity of radioactive materials, will be required to watch a video on the hazards that could occur while working around radioactivity.


Postings and Marking of Areas and Equipment

“Postings” can be any number of the signs shown below:

                                        Caution,                                                                   Lab Safety Rules                                                  

                                        Notice to Employees,                                               Notice to Workers   

                                          Container Labels                                                      Radiation Tape        


Each laboratory or area where radioactive materials are used or stored must have posted at the entrance a CAUTION RADIOACTIVE MATERIALS sign, IDPH regulations, Notice to Employees Notice to Workers,  and Lab Safety Rules.  The sign must include the name and after-hours phone number of the Authorized User.  Entry warning signs are to be posted and removed only by the RSO.

Radiation Area 

Areas where radiation levels might expose a person to any level of radioactivity (above background) must have the required postings.

Radioactive Material Work Areas

Areas used for work with unsealed radioactive materials must be clearly marked with CAUTION RADIOACTIVE MATERIAL tape. 

Storage Areas and Containers

Refrigerators, freezers, and other “in lab” storage areas and containers in which radioactive materials are stored or transported must have a visible CAUTION RADIOACTIVE MATERIAL label.  Labels should be removed from containers that are empty and not contaminated.


Laboratory equipment (flasks, beakers, centrifuges, etc.) containing radioactive materials should be marked with CAUTION RADIOACTIVE MATERIAL tape.

Contaminated Areas and Equipment

The RSO may mark areas and equipment to indicate significant levels of contamination found during periodic surveys.  These markings are to be removed only after the article or area has been decontaminated.


The RSO may specify additional postings to control access or ensure safe operations.

Laboratory Safety Practices

Hazards associated with working with radioactive materials can be minimized through appropriate use and design of facilities and by adherence to standard safety rules and practices.

Through a number of standard procedures, practices, and rules, ALARA can be maintained in the laboratory and the classroom. 


Protective clothing will be worn when working with radioactive materials.  This includes laboratory coats, gloves, and safety glasses. Sandals and bare feet will NOT be permitted in the laboratory.


Pipetting by mouth is extremely dangerous and will not be done under any circumstances.

Food and Cosmetics

Smoking, eating, or drinking shall not be permitted in laboratories where radionuclides are being used.

Food, beverages and their containers shall not be permitted in the laboratory or classroom.

Cosmetics will not be applied in the laboratory where radioactive materials are used or stored.

Personal Care

Do not work with unsealed radioactive materials with open cuts, sores, etc. on exposed skin areas, even if bandaged.

After handling radioactive materials, be sure to wash hands thoroughly before handling food, tobacco, etc.

Work Areas

Radionuclide work areas will be clearly designated and in so far as possible, isolated from the rest of the laboratory. Work with volatile radionuclides will be confined to a fume hood.

Practice First

Procedures involving radioactive materials should be well planned and, when unfamiliar to the user, should be practiced with non-radioactive materials.


Persons who have not been approved for radionuclide use shall not work with or handle radioactive materials.  The Authorized User is allowed to have someone working with them who is not on the license. This person must be directly supervised at all times by the AU.


Dosimeters are usually not required for the radionuclides currently on the license.  They can be made available for anyone who wishes to wear one.  The RSO can recommend a company from which to purchase them, however, the department the AU is working under must purchase them and pay for the tests.

Container Use

All containers of radioactive materials and items suspected or known to be radioactive will be properly labeled (i.e., with a tag or tape bearing the radiation logo and the word radioactive).

To avoid spills, use metal or plastic outer trays or beakers to carry liquid radioactive materials.

Lab Surveys

Every nuclide user will perform a radiation survey at the conclusion of each procedure.  All items found to be radioactive will be disposed of or cleaned properly. Any surface found to be contaminated will be labeled and decontaminated before further use. 


A record of the types and quantities of radionuclides possessed by each authorized user at a given time will be maintained.

Radioactive Laboratory Requirements

At the University of Northern Iowa, only labs specified on the current Radioactive Materials License can be used for radioactive materials research. For certain types and uses of radioactive materials however, additional facility requirements (shielding, etc.) must be met.

The RSO must be notified prior to any use outside of these specified labs.

In general, the following are minimum facility requirements for the use of radioactive materials:

Requirements for Specified Radioactive Labs

Floors must have smooth, nonporous, easily cleaned surfaces.  Appropriate floor materials include vinyl, tile, and sealed concrete. Postings must be in a visible place on the entryway door.  Areas which will be used for radioactive materials must be marked with tape stating that radioactive materials are used in the area.Benches must have nonporous, easily decontaminated surfaces.  Surfaces of high quality polymer or stainless steel are preferred.sinks should be stainless steel or of seamless molded construction.  Sinks must be labeled as a sink where radioactive materials are permitted to be dumped.  They must also have the radioactive materials postings by them. Hoods, when required, are preferably constructed of stainless steel or molded fiberglass. Air flow rates measured at the hood front opening must be a minimum of 75 linear feet per minute.  The hoods must also have the radioactive materials postings and be ASME certified. The ventilation rate for the entire lab should be 5 to 10 air changes per hour.  The actual rate required will vary with the potential for radionuclide release to the air within the particular laboratory. Shielding shall be provided when appropriate. Specific requirements will be determined in consultation with the RSO on a case by case basis.

Shielding When not in use, radioactive sources and stock solutions in the laboratory must be stored or shielded so that radiation levels in occupied areas will not expose persons unnecessarily.  These storage areas must be locked and controlled by the A.U.

Low and intermediate energy beta (H-3, C-14, S-35)These do not usually represent an external radiation hazard and do not require shielding
High energy beta (P-32, Sr-90)These should be shielded first with at least ¼” thick Lucite.  Lead can then be used, if necessary, to shield any bremsstrahlung x-rays produced in the Lucite.
Gamma (I-125)These should be shielded with lead.


Contaminated Items

Any small items that become contaminated (paper, clothing, etc.) must be double bagged.  Contact the RSO as soon as possible to arrange to have the bag placed in Radioactive Waste Storage.


Radioactive waste must be doubled bagged and placed in a closed, labeled container.  Liquids must be kept separate from solids.


Sharp items such as razor blades, needles, broken glass, etc., shall be placed in a suitable “sharps” container and properly labeled.

Guidelines for Laboratory Surveys

Surveys of Work Areas

In order to ensure that safety rules are observed and that radioactive materials have been adequately controlled, the RSO will conduct audits of radionuclide laboratories periodically. During the audit, both external radiation levels and surface contamination levels are monitored.  Also reviewed at this time are the Authorized User’s radionuclide inventory, survey records, wipe test records and drain disposal records. 

Radioactive Material Inventory Form       Routine After Use Survey Form         Drain Disposal Log

The Authorized user is required to survey their work areas (hoods, bench tops, sinks, floors, etc.) after each experiment and at any time there is a reason to suspect a spill or contamination incident.

Laboratories are required to keep written documentation of contamination surveys and send a copy to the RSO. 

Required surveys are listed in the table below.

Type of SurveyFrequencyPerformed byDocumented
Routine SurveyAfter each experiment and at any time there is a  reason to suspect a spill or contamination incidentUserYes
Radiation SurveyPeriodicRSOYes - in EH&S office
Annual SurveyAnnuallyRSOYes - in EH&S office


*Internal surveys will be required until the laboratory has had four consecutive Radiation Safety surveys with no high level contamination found.

Survey Meters

Authorized Users must use calibrated radiation survey meters for quantitative measurements in laboratories where radioactive materials are used.  They must also be used for wipe tests on received materials, after use surveys, spill, and all documented incidents.

Authorized Users must know how to use the survey meters.

Recommended Instruments

Low Energy beta(H-3)Liquid scintillation counter for wipe surveys
Intermediate energy beta (S-35, C-14, P-33)G-M survey meter; Liquid scintillation counter for wipe surveys.
High energy beta, P-32, Sr-90)G-M survey meter.
Low energy gamma (I-125)Liquid scintillation counter or gamma counter for wipe surveys.
High energy gamma (Co-60)G-M survey meter


Location of Survey Equipment

Equipment Model #/Serial #Location

Victoreen 1700


BEG (PHY) 14

Ludlum Model 12 A007476


BEG 302

Ludlum 161377


Civil DefenseMSH 168A

Ludlum 185423


MSH 081

Ludlum 141009


Civil DefenseBEG (PHY) 14
Civil DefenseBEG (PHY) 14

Ludlum Model 3


ITT 249



MSH 205B

Beckman LSC 6500


MSH 076

Maintenance of Survey Equipment

The RSO will coordinate the annual calibration of all survey equipment.  Every 12 months, he/she will collect survey meters from the rooms listed above and send them to a designated facility for calibration/repair at the expense of EH&S.  The batteries for the survey meters will be replaced at that time.

It is the Authorized User’s responsibility to make the survey meters available for calibration and notify the RSO if a meter is not working properly so it can be sent to the designated facility for repair.

The RSO will also coordinate the annual calibration/maintenance of the Liquid Scintillation Counter by a certified technician.  If at any time the machine does not work properly, the authorized user must contact the RSO to have the machine repaired.

Control of Radioactive Material

Radioactive Materials Controls

Authorized Users are only allowed to use materials on application as approved by the RSC.  Materials must not be loaned or transferred to persons not named on the license.  Transfer to a person named on the license must be approved for use by the RSC and reported to the RSO.  It must also comply with use described on the application submitted to the RSC.  An amendment to the license must be made before any changes take place.

Loss or Damage        

The loss, disappearance, or damage of radioactive materials or radiation sources must be reported to the RSO immediately upon discovery.  The RSO is responsible for the notification of the IDPH.


The RSO maintains the campus running inventory of all incoming and outgoing shipments of radioactive materials, including waste. 

Semi-Annual Report by Authorized User

Each Authorized User is required to report every 6 months the amount of radioactive material on hand.

Radioactive Waste Disposal Procedures

Waste Disposal Procedures

The RSO is responsible for the storing and maintaining of all radioactive waste generated at the University of Northern Iowa.  In order to facilitate this process, Authorized Users are required to follow a number of specific procedures regarding radioactive waste generated in their laboratories.

Preparing for Pick-Up

  • To dispose of radioactive waste, pick-up must be coordinated with the RSO.  Preparation includes:
  • Test the container for exterior contamination.
  • Seal all containers properly.
  • Disinfect any waste that contains biological, pathogenic, or infectious materials with a biocide prior to pick-up
  • Separation by Isotope
  • Radioactive waste will be separated and labeled according to Isotope.  The RSO will determine the half-life and further categorize the waste. 


An Authorized User may dispose of liquid waste IF a time period of 10 times the half-life has passed.  If this amount of time exceeds 24 hours, then the RSO will be called to coordinate storage of the liquid containers.  The containers are to be double bagged prior to placement in storage.  The liquid will then be placed in the Waste Storage Area until the 10 times the half-life period has passed.

The liquids need to be identified by isotope and if biodegradable or hazardous waste.

All drain disposal must be limited to a designated radioactive materials drain.  Drains, used for disposal, must be approved by the RSO and posted as to which specific isotope is being dumped.

Any drain disposal of radioactive materials must be documented on the Drain Disposal Log indicating the isotope, AU, and the date of disposal.

Solid Waste

Solid waste should be double bagged and labeled according to isotope.  The RSO should be called to coordinate storage of radioactive materials.  All radioactive material will be stored for 10 times the half-life or until alternative disposal is contracted. 

Mixed Hazardous/Radioactive Waste

Radioactive waste containing any hazardous chemicals requires special handling.  The RSO must be consulted before any such waste is stored.

Storage of Radioactive Waste

The RSO has sole access to the storage room for radioactive waste.  The RSO is also responsible for organizing the waste into short-lived and long-lived radionuclides.  The purpose of this storage is to allow time for the decay of waste containing short-lived radionuclides and to facilitate the proper disposal of all radioactive waste.

Scintillation Vials

All scintillation vials must be kept for 10 times the half-life of the isotope.  They must be capped and labeled according to their isotope.  If 10 times the half-life is longer than 24 hours, the RSO must be called and the vials will be double bagged and placed in waste storage.


Radiation Dose Standards

Permissible occupational radiation dose levels are set by the Iowa Department of Public Health, and are available in the “IDPH Research and Development, Laboratory, and Industrial Use of Small Quantities of By-Product Material Regulatory Guide”, Appendix A.

Current limits for occupational radiation exposure have been established at levels which, in light of present knowledge, should prevent all acute radiation effects (e.g., erythema, epilation); and limit the risks of late effects such as cancer or genetic damage to very low, “acceptable” levels.

UNI has established investigational levels for occupational external radiation dose which when exceeded will initiated and investigation by the RSO. Investigation levels that have been adopted are shown in Table 1. These levels apply to the exposure of individual employees and student researchers

Table 1

Limits for Occupational External Exposures to Ionizing Radiation Investigation Levels (mrems per month)

 Level 1Level 2
Whole body; head and trunk; active blood forming organs; gonads200400
Skin of whole body, extremities20004000
Lens of Eye6001200


The RSO will review and record on IDPH Form, “Current Occupational External Radiation Exposures,” or an equivalent form (e.g., dosimeter processor’s report) results of personnel monitoring not less than once in any calendar quarter as required by 641-10.100.  The following actions will be taken at the investigational levels as state in Table 1:

  • Personnel dose less than Investigational Level I. Except when deemed appropriate by the RSP, no further action will be taken in those cases where an individual’s dose is less than Table 1 values for the investigation Level I.
  • Personnel doses equal to or greater than Investigation Level I but less than Investigational Level I but less than Investigational Level II.
  • The RSO will review the dose of each individual whose quarterly dose equals or exceeds Investigational Level I and will report the results of the reviews to management as soon as completed. If the dose does not equal or exceed Investigational Level II, no action related specifically to the exposure is required. The RSO and management will, however, review each such dose in comparison with those of others performing similar tasks as an index of ALARA program quality.
  • Personnel dose equal to or greater than Investigational Level II. The RSO will investigate in a timely manner the causes of all personnel doses equaling or exceeding Investigational Level II and, if warranted, will take action. A report of the investigation and any actions taken will be presented to the management following completion of the investigation. The report should include a copy of the individual's Form IDPH 588-2834 “Occupational Exposure Record for Monitoring Period” and 588-2833 “Cumulative Occupational Exposure History” or its equivalent.
  • Re-establishment of investigational levels to levels above those listed in Table I.
  • In cases where a worker's or a group of workers' doses need to exceed an investigation level, a new, higher investigational level may be established with good ALARA practices. Justification for new investigational level will be documented.
  • The RSC will review the justification for and must approve all revisions of investigational levels.


Radiation dose limits for radiation workers under the age of 18 are 10% of those listed above for adult workers.


The human embryo and fetus are particularly susceptible to damage from ionizing radiation. The National Council on Radiation Protection and Measurement (NCRP) recommends that the whole body dose received by a female worker during the 9 months of her pregnancy not exceed 500 mrem (one-tenth of the normal occupational dose limit). 

If a woman is a radiation worker, she must be instructed of her rights as far as pregnancy is concerned.  A woman has the right to declare, undeclare, or not to declare if she is pregnant. 

Declared Pregnancy

The pregnancy, if chosen to declare, must be declared in writing to her employer or the licensee (if her employer is not the licensee) and a copy to the RSO.  In this case, she will be assigned a fetal dosimeter or temporarily assigned to a different job. 

The dose limit for the embryo/fetus of a declared pregnant worker is 500 mrem over the course of the pregnancy, with no deviation above 50 mrem in any month. 

Undeclared Pregnancy

The woman has the right to undeclare a declared pregnancy at any time if she no longer wants the pregnancy considered for employment (job assignments) or dose reduction purposes.  In which case, the reduced fetal dose will not apply.

Not Declaring a Pregnancy

Alternatively, she may choose not to declare her pregnancy at all, in which case the reduced fetal dose limit would not apply.

Members of the Public (MOP) 

Anyone entering the area where radioactive materials are being used or stored who is NOT on the license, is considered a Member of the Public and must be discouraged from entry. 

The dose limits for MOP are 100 mrem per year or 2 mrem per hour.    

The Authorized User is responsible for any MOP coming into the area.  Access must be restricted to the AU, RSO, and anyone supervised by the A.U. 

ALARA Guidelines

In practice, radiation doses should be As Low As Reasonably Achievable.  ALARA is a guideline meant to strike a balance between the cost of radiation protection and the health benefit derived from that protection. 

It is the responsibility of everyone including radiation workers, Authorized Users, the RSC, and the RSO to operate within the ALARA guideline.  This is achievable by outlining safety procedures for radiation environments and by monitoring the workplace environment to control contamination and minimize doses.


In the case of non-compliance with radionuclides, the RSO has the right to take immediate action if conditions warrant.  The misuse of radionuclides or equipment will be reported to the RSC to determine the consequences to the Authorized User at fault. 



Reviewed by the Radiation Safety Committee on September 8, 2023

Reviewed by Risk/EHS on June 9, 2022


Contact Name: 

Gordon Krueger

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