FAQs for Radiation Safety
You can find most answers to questions regarding
radiation safety in the University of Kentucky Radiation Safety
Manual. A copy of the manual should be available in laboratories
belonging to Authorized Users of radioactive material. If you do not
have a copy in your laboratory and should have, contact the Radiation
Safety Office at 3-6777.
- How do you fill out a waste ticket to notify Radiation Safety to pick up radioactive waste?
All radioactive waste to be picked up by Radiation Safety must have a waste ticket. To learn how to complete the ticket to the website Radioactive Waste
- How do you complete the monthly radioactive
material inventory form?
Monthly inventories are required from
all Authorized Users. Go here to learn how to complete the form.
- What type of shielding and how much do I need for a particular radioisotope?
A table providing shielding information can be found here.
- Why do only certain individuals need to wear
Dosimetry is issued to an individual based on the likelihood that individual will receive greater than 10%
of the occupational exposure limit. The policy for wearing dosimetry
may be found in Chapter
9 of the Radiation Safety
Manual or at the website titled Obtaining a
- What are the requirements for separating
Primarily waste must be separated
according to waste type (i.e. liquid, solid, liquid scintalation
vials, animal carcass). In add it is important to separate waste
according whether it contains long-lived or short lived material. The
requirements for separating waste may be found in Appendix G of the Radiation Safety
Manual or the website titled Radioactive
- How do I perform a wipe test?
Go here to
learn how to perform a wipe test.
- Why do I need to perform wipe tests when I have
not used radioisotopes for so long?
All active Authorization require, at a
minimum, monthly wipe tests. If you are not actively using
radioactive material in your laboratory you should consider going on
inactive status or closing out your authorization. If you go on
inactive status, you only need to perform wipe tests on a quarterly
basis. While if you close out your laboratory you do not need to
perform wipe tests at all.
- How do I complete the scintillation drum sheet
for a multi-user laboratory?
The authorized user responsible for
the room should have their name at the top of the sheet designated
the Authorized User. Multiple users list their name on the form next
to the radioisotope and activity that they are adding to the drum.
These individuals may be other Authorized Users or their
- Why do we only track radioisotope in the
The purpose of the tracking is to
document the disposition of the activity of the order. The vial has
been assigned a shipcode by the Radiation Safety Office. If you were
to aliquot several substocks from one shipcode for use at a later
date, the activity on hand in the aliquots would remain in your
inventory. Using the subtraction system of inventorying with our
database, the activity in the aliquots remains in the Authorized
User's account until it has been assigned to a waste stream via the
radioactive materials monthly inventory form.
When the total activity of the vial has been
disposed, the shipcode will be deleted from your account.
If a significant activity of the materials will
remain in samples in the laboratory, the shipcode may be active for
- How do I know if I had an over exposure?
If you receive an exposure in excess
of the ALARA Notification Levels you will be notified in writing. See
9 of the Radiation Safety
Manual for the notifcation levels. If you
exceed the occupational limits for exposure you and your supervisor
will be notified immediately by the Radiation Safety Officer.
- Why do our meters work so much better than their meters?
The annual calibration done on all
meters at UK ensures that the dose rate reading from a specific
source is within +/- 10% of the standard. Contamination detection is
not that simple.
The reading from a GM meter is proportional to the
number of ionizing events counted in the gas filled chamber of the
instrument and is also affected by the voltage setting of the meter.
The pancake detectors we use are more expensive, but they also have a
larger window than an end window. Therefore more counts from a given
source are detected by the larger face. Newer instruments would be
closer to the ideal voltage set at the factory, which could change
with age, and lower the efficiency. All of our instruments are
Therefore, the size of the detector, the thickness
of the window, and the operating voltage all can effect how well a