Becoming a Radiation Worker | Environmental Health & Safety

In order to handle Radioactive Materials on MU's campus, each individual must become an approved Radiation Worker (RW). A Radiation Worker is an individual trained in radiation safety who is approved to work under the permit of a Permitted Individual (PI) with radioactive material without direct supervision. The PI is responsible for each RW and their acts of commission or omission who are approved to work under the permit. A RW may work under more than one permit at a time but must be approved by each PI. Please review the information on this page prior to contacting a member of the Radiation Safety Staff with questions on becoming a RW.

Specific instructions to become a Radiation Worker

Select the area in which you will be working to find specific instructions for becoming a Radiation Worker.

Additional information on this page related to becoming a Radiation Worker or maintaining Radiation Worker status include:

Completing Refresher Training if you are already a Radiation Worker
Removing a Radiation Worker from a RAM permit
Importing Large Numbers of Radiation Workers to EHSA
Working with Generally Licensed Devices only
How to register a new user in EHSA for radiation use

Additional Frequently Asked Questions:

Refresher Training Information

RWs working in research laboratory or veterinary medicine clinical settings are required to complete radiation safety training once every three years. RWs working in a clinical setting with humans must complete training once every year.

If you are a RW in a research laboratory setting, go to the Radiation Safety Online Training page and complete the course EHS 490 Radiation Safety Training at MU. Training is required every 3 years.
If you are a RW in a veterinary medicine clinical setting, go to the Radiation Safety Online Training page and complete the courses EHS 490 Radiation Safety Training at MU and EHS 492 Veterinary Medicine Specific Radiation Safety Training. Both of these trainings are required every 3 years.
If you are a RW in a human clinical setting, go to the Radiation Safety Online Training page and complete the courses EHS 491 Radiation Safety Training at MU and EHS 493 Radiation Safety Training for Human Medical Use. Medical radiation safety training is required annually. Note that you can complete the required trainings through Cornerstone rather than EHSA. Just be aware the course numbers are different! Instead you will take WBT 182 and WBT 183 annually every year by April 30 when other hospital trainings are due.
If you wear a dosimeter, then you will need to take EHS 480 Dosimetry Training once every three years. If you are a hospital worker, you can complete this training through Cornerstone where it has the courese number WBT 184 instead.

Removal of Radiation Workers

When a RW is no longer working under a RAM permit, submit a request to remove an individual through EHSA. See the tutorial video "Add/Edit Worker to a Permit" on the Tutorials page for assistance. If dosimetry needs to be cancelled, add a comment in the request.

Importing Large Number of Radiation Workers into EHSA

If you have a large number of workers (>10) that need to be added to EHSA so that training can be accessed, email rad@missouri.edu to obtain a copy of the spreadsheet import file. When filling out the spreadsheet,

Make sure that every cell is filled out properly. Submissions will be rejected if the spreadsheet is not filled out correctly.
Pawprint needs to be the University assigned pawprint, not the alias. Using a worker's alias will further delay their access to training.
If adding the workers for the first time to EHSA, then the PI will need to be the "Radiation Safety, Training" RAM permit. If all workers have completed training already and need to be directly added to their PI's RAM permit, then specify the PI's name under the "PI Name" column.
Worker Function must be selected. A worker function determines a worker's training course. See the Radiation Safety Training page for a description of each available worker function.

This spreadsheet can also be used to remove a large number of workers from a RAM permit. Fill it out in the same manner as adding workers. Submit all spreadsheets to your assigned Health Physicist or rad@missouri.edu.

Generally Licensed Device Only Users

A generally licensed device, or GLD for short, is defined by the NRC as a device containing radioactive material that is typically used to detect, measure, gauge, or control the thickness, density, level, or chemical composition of various items. Examples of such devices are gas chromatographs (detector cells), density gauges, fill-level gauges, and static elimination devices. If you plan on working with RAM only in the form of a GLD, then requirements may slightly differ when applying for a RAM permit or becoming a Radiation Worker. Radiation Workers who exclusively work with GLDs will only need to take EHS 490 Radiation Safety Training at MU. If you are unsure if you fit into this category, contact the Radiation Safety Staff at rad@missouri.edu for assistance.

EHSA Login and Training Issues

If you are having issues logging into EHSA for the first time, there are a couple of steps to check before contacting Radiation Safety with questions

I tried my MU credentials, but I'm getting the "Invalid login credentials" error.

If this appears, you may not have a profile set up in EHS Assistant. Select the "First-Tume User?" button and fill out all the questions that appear. Make sure to select the Permitted Individual as Radiation Safety, Training. Select the permit R-00180 for ram or ram and x-ray use, or select the permit R-00021 for x-ray only use. Also select the worker function. Failure to select a worker function can delay access to EHSA.

I don't know what my worker function should be, why is that important?

Worker functions are used in EHSA to assign training. If you do not select a worker function, the Radiation Safety Staff will have to follow up with you to determine your job duties; this can delay access to EHSA. Selecting a worker function during the initial process speeds up your access. You can review a list of available worker functions on the Radiation Safety Training webpage.

I tried to select the "First-Time User?" button, but I'm getting an error saying "Login ID could not be validated. Please contact your administrator."

This error means that you already have a user profile in EHSA and will not be able to complete worker registration yourself. If you receive this error, you will need to contact your Permitted Individual or Lab Manager. EHSA has different access rights based on your job function. Once logged into EHSA, the worker registration button only appears for AUs, PI, and their delegates. It also only appears if you do not have a profile in EHSA. If your AU or PI does not know how to fill out the worker registration, direct them to the tutorial video "Add/Edit Worker to a Permit" where they can request to add you to the Radiation Safety, Training permit. They should not request to add you to their own permit because you have not completed your required training(s) yet.

I've followed all the steps to get access to EHSA, and I'm still getting a login error saying "Invalid login credentials."

At this point, if you have followed all the steps correctly and still receive this error, then contact the Radiation Safety Staff at rad@missouri.edu. It most likely means that your access rights were not set up correctly during the worker registration process.

I have access to EHSA and I'm on a chem/bio permit, why isn't my radiation safety training course showing up in the training portal?

As of 2024, all radiation safety training for radioactive materials is hosted directly in EHSA. If you are not on a permit and not assigned a worker function, then the course will not show up on the training portal as a required course. However, you can search for the course by scrolling down until you see the course you need, then clicking "start". This process is show in more detail in the "Access EHS Training Courses and Training Records" video on the EHSA tutorial video page.

Page last updated on July 10, 2025.