Environmental Health & Safety
Supporting the campus community by proactively protecting people, property and the environment in a responsible and cost effective manner.

Radiation Safety Frequently Asked Questions

Section 1

Radiation Safety Frequently Asked Questions

Ordering Radioisotopes
Radiation Use Authorizations
Radioactive Waste Procedures




What is a radiation dosimeter?

A radiation dosimeter, commonly called a ‘ radiation badge', is a device containing radiation sensitive material that stores dose information for ionizing radiation of sufficient energy to penetrate the outer cover and selective filters.


Do I need a dosimetry badge and ring?

Any person working with radioactive materials or radiation-producing machines who could receive a dose in excess of 500 millirems in a year is required to wear dosimetry. However, we typically provide dosimetry to many more people than are required. Historically, results from these dosimeters demonstrate that doses are nearly always undetectable or very low.

If you work with only 3 H, 14 C, 35 S, 33 P and/or 45 Ca, a badge will not be issued since the low energy of the radiation these isotopes emit cannot be detected with a badge.


How do I obtain a dosimetry badge and ring?

You must first complete the Radiation Safety Part I course. Once this is completed, you can request radiation dosimetry by filling out the Dosimetry Request Form . All fields must be completed.

You can fax this form to EH&S at (949) 824-8539 or forward it through intercampus mail to: Radiation Safety, EH&S, Zot 2725. Your dosimetry badge and/or ring will be sent through campus mail within 5 working days. An e-mail will be sent notifying you of the date the badge was placed in the mail.


How often are dosimeters exchanged?

Campus dosimeters are exchanged on a quarterly basis. Every quarter (starting on the 1 st of January, April, July, October) dosimetry badges for the previous wear period are collected and exchanged for new ones. The badges are processed by Global Dosimetry Solutions (GDS), our dosimetry company. We typically receive the results within 60 days. It is possible to request an "emergency" reading of a dosimetry badge, for which GDS charges an additional $50.00. This is done only if a high dose is expected.


What if my badge is lost? Who do I contact?

If you lose a dosimeter, notify your supervisor and contact Radiation Safety immediately at 949-824-6200. There will be a cost to replace a lost badge.

We will provide you with another dosimeter. You will be contacted by one of our staff to complete a Lost Badge Report form to ensure that we have a reasonable approximation of your dose (from the lost badge). Note: There will be a recharge for the time that it takes to perform this evaluation.


When does the report have to be completed?

Immediately after you lose your badge. Do not wait until the end of the monitoring period to tell us that you lost your badge – this indicates to us that you worked without a badge during the period. Do not perform work with radioactive materials without your badge if one is required.


What if I find my badge after I've already notified EH&S that it's been lost?

If you have already been charged the lost fee, this will not be refunded. However, if the badge is less than one year old, return it to EH&S, Zot 2725, as the dosimetry company may be able to salvage the components. If the badge is more than one year old, you may discard it.


When is my badge considered late?

The due date for the badges is the 21 st of the month following the end of the quarter. See the table below for due dates for each quarter. Badges received after the due date are considered late and will be assessed a $10 late fee.


Due at EH&S

Fee after due date

2nd Due Date
with penalty fees

2 nd Fee after due date . Penalty fee – lost and late

Jan. 01 - March 31

April 21st


May 21st


April 01 - June 30

July 21st


August 21st


July 01 – Sept. 30

Sept. 21st


October 21st


Oct. 01 – Dec. 31

January 21st


February 21st


If you know you will be away at the time that the badges are due, be sure to make arrangements to get your badge to EH&S before the due date.


Why is it so important to turn the badge in before the due date?

As the badge ages, radiation dose readings from the badge can become unreliable. Also, if there is a dose on the badge, it is important to get the reading as soon as possible. Since UCI issues badges on a quarterly basis, late badges may have to wait up to 7 months to be processed. If any actual dose was received, this can defeat the purpose of even having a badge.


What is the difference between a late badge and a lost badge?

A badge is considered late if it is received after the 21 st of the month following the end of the quarter. The charge is $10.00 per badge.


Due at EH&S

Jan. 01 - March 31

April 21st

April 01 - June 30

July 21st

July 01 – Sept. 30

Sept. 21st

Oct. 01 – Dec. 31

January 21st


A badge is considered lost if it i s not received after the 21 st of the second due date.


2 nd Due Date
with penalty fees

Jan. 01 - March 31

May 21 st

April 01 - June 30

August 21 st

July 01 – Sept. 30

October 21 st

Oct. 01 – Dec. 31

February 21 st


For each badge not received and considered lost, our dosimetry company, GDS, charges us $20.00. In addition, you will be charged the $10.00 late fee for a total change of $30.00 per badge. This charge is then passed on to the wearer.


How do I cancel my dosimeter?

To cancel your dosimetry service, you must complete the Dosimetry Cancellation Form, available on our website at https://www.ehs.uci.edu/radsafe.html . The completed form may be faxed to Radiation Safety at (949) 824-8539 or mailed to EH&S, Zot 2725.


What is a Dose Record?

A dose record is documentation of one's dose due to ionizing radiation. It is a cumulative record that follows a worker from job to job; therefore, it is a lifetime record. If you leave UCI and are issued a dosimeter at another institution, your new employer will contact us to request your dose record while at UCI. We are required by State regulations to comply by providing your dose record.


What information is required for a Lost Dosimeter Report?

A lost dosimeter report assists EH&S in determining an estimate of the dose that would have been received if the dosimeter had been read. Therefore, in order to estimate that dose best, we must rely on you to provide information that is necessary to perform this estimation.

In an ideal dose estimate, we would know the dose rate and the time that you were in the area where that dose rate existed. Very simply, if the dose rate was 5 mrem/hour and the person worked in that area for 5 hours, the dose reported would be 25 millirem.

However, very few dose estimates are simple and people will not typically remember all of the radiation procedures they have performed or have a good feel for the dose rates that they were exposed to in the course of a monitoring period. As a result, we try to make the best possible guess at the dose that people may have received based on previous badge results or the dose that people doing similar work receive in the same monitoring period.

We know that we cannot determine your dose to the exact value that your badge would report, but we can be reasonably sure that the dose received will not be substantially different from the estimate.


When does the lost dosimeter report have to be completed?

Your memory about the radiation work that you did during the period for which the dosimeter was lost will be best immediately after you lose your badge. If you lose it today – call us today!


Why is a lost badge of such concern?

Your dose record is meant to be a continuous record of your exposure to ionizing radiation, so you should obtain another dosimeter if yours is lost. Since the dosimeter data from your lost badge is now unavailable, the RSO must make an estimate of your exposure for the period that the badge was worn. Dosimeters range in cost from $3.00 to $10.48 per monitoring period. Replacement costs are higher.




How do I order a radioisotope for my laboratory?

Your Principal Investigator (PI) must be authorized for the radioisotope in the desired quantity and chemical form. All orders for radioactive materials must be placed using a high value purchase requisition. These requisitions must be forwarded to UCl Purchasing. Make sure to indicate that the order is for radioactive material and include your PI's name and RUA number.


Where do I pickup my radioisotope shipments?

All radioactive packages are processed by EH&S and made available to the labs the same day they are received on campus. After EH&S is finished logging in and checking your package for contamination, your laboratory will be notified by phone that a shipment has arrived. Wait for us to call you; as soon as your package is known to be contamination-free, we will contact you with a delivery location and time.

If it has been more than 30 days since we have inspected your contamination monitoring (wipe test) records, you will be asked to bring your most recent wipe test results with you when you pick up the package. If you fail to do so, you may not be able to pick up your shipment.


What if I miss the delivery van?

After 3:00 pm, any packages which were not picked up are taken back to EH&S. You may contact EH&S at (949) 824-6200 if you would like to come by and pick up your package after 3:00 pm. EH&S is open until 5:00 pm daily. Packages not picked up will be placed on the van for re-delivery the following day.


What if a package is delivered directly to my lab?

All radioactive packages are supposed to be delivered to EH&S. If a package is delivered directly to your lab by mistake, contact EH&S immediately. Do not open the package. We will retrieve the shipment and, after processing, make sure you get it back the same day.




How do I apply for an RUA?

The Principal Investigator (PI) of a UCI lab applies for an RUA using our application form . Use of radiation sources may proceed after the approval of the application. The Radiation Safety Committee meets quarterly to formally review all RUA applications.


What if I want to add something or make changes to my RUA?

Requests for changes to an RUA may be e-mailed to the Radiation Safety Officer at radsafe@uci.edu . Requests take only a few days to review and approve. Upon approval, you will be sent an updated RUA.


How do I cancel my RUA?

Notify Radiation Safety of your intention to cancel as soon as possible. It is requested that you provide notification at least 30 days prior to allow plenty of time to complete tasks such as radioactive waste pick-up and closeout surveys.



What do I do when my waste container is full?

An online waste pick-up request must be submitted. It is encouraged that lab personnel arrange for pick-up before the waste container is completely full to prevent overflow. New waste containers can be supplied free of charge at the time of the waste pickup.




What type of training is required to use radiation sources at UCI?

All radioisotope users must receive radiation safety training from EH&S before beginning work with radioactive materials or radiation-producing machines. Depending on the work performed, additional instruction may be required.


How do I sign up for Radiation Safety Training?

Registration for the Radiation Safety Part I & Part II is through the UC Learning Center. Go to the sign-in page at http://www.uclc.uci.edu to log in and sign up for classes. If you do not yet have a UCINetID because you are a guest at UCI or have not paid your student fees, please send an e-mail to radsafe@uci.edu and you will be added to the roster manually.


Is my training applicable to other institutions?

It is rare that future training requirements at other institutions will be waived due to instruction you received at UCI. Most institutions are required by federal and state law and/or their radioactive materials license to provide basic training to all new users. While the principles of radiation safety will be the same in most research settings, policies such as emergency procedures, radioisotope ordering, and waste disposal will vary from one institution to the next. As such, it is important that new users be re-trained when they move to a new facility.


Do I need training to use a cesium irradiator?

Yes. In addition to completing EH&S radiation safety training, you will also need to receive specific training from the Principal Investigator responsible for the irradiator. You will also be required to wear dosimetry.




My survey meter isn't working properly. What do I do?


Perform a battery check. If they have a low charge, replace the batteries. Check the cable connections. If any are loose, tighten them and test the meter operation again. Determine if sudden movement of the probe or cable causes spurious counts. This indicates that the cable may need to be replaced. You may request a new cable from Radiation Safety (Ludlum meters only) or you may contact the vendor directly to obtain a replacement. If none of the above steps resolve the problem, bring the meter to Radiation Safety for further inspection. It is possible that the meter may need a new detector tube or it may need to be sent back to the vendor for repair.


What should if I do if my lab is moving to a new location?

Notify your EH&S Safety Coordinator of your situation as soon as possible. It is requested that you provide notification at least 30 days prior to allow plenty of time to complete close-out tasks such as waste pick-up, transfers, final radiation surveys and changing the authorized locations on the RUA.


What should I do if I'm planning laboratory renovations?

Notify your EH&S Safety Coordinator of your situation as soon as possible. It is requested that you provide notification at least 30 days prior to the move to allow plenty of time for our office to instruct you and your lab regarding pre and post-work surveys and impact analysis.


What should I do if I become pregnant while I am a radiation worker?

Women who become pregnant as radiation workers have the right to formally declare their pregnancy in writing to EH&S. The decision of whether and when to declare pregnancy is left entirely up to the worker. Once a pregnancy is declared, fetal exposure is limited to 500 mrem (one tenth the occupational limit) for the entire gestational period. For more information on declared pregnancy and prenatal radiation exposure, refer to NRC Regulatory Guide 8.13 . We ask that you contact the Radiation Safety Officer for consultation prior to declaring a pregnancy or if you have questions/concerns regarding prenatal radiation exposure.

If you do not find your question in this page, please call our office at (949) 824-6200 and we will gladly address your question.