RULES FOR THE USE OF RADIOACTIVITY
You must be
certified by EHS before you can use radioactivity. The guiding principle is COMMON
SENSE. I take radioactive
use seriously—ALL of the following guidelines MUST be followed, or I will get very upset!
- We will primarily be using 32P, 35S,
125I, 14C, and 3H. Please familiarize yourself with
the properties of these compounds (half lives, ionization potential,
- All 32P source
vials must be opened in the fume hood and behind a plexiglass
shield. ALWAYS keep the proper waste container within 2 feet of your immediate
- Discard 32P in a 32P waste, and
35S in a 35S waste, etc. DO NOT mix isotopes, or
else EHS will get upset.
- Wear gloves when handling radioactive samples. Lab coats are recommended, but I
don’t insist on their use.
- A geiger counter should be ON
(with sound preferably OFF) and within 2 feet of your work area. Please direct the probe of the
counter AWAY from your work area.
- Your work area should be covered with an absorbent pad. You may use your pipetmen for
pipetting radioactivity, but always check the tip of your pipetman with a
geiger counter after ejecting the tip to ensure that it is not
contaminated. If it becomes contaminated, IMMEDIATELY wash the tip
with warm water and soap.
Any delays could result in long term contamination of your
pipetman. Filter tips are
useful to prevent contamination.
- Eject tips directly into a radioactive waste
container (which is never more than 2 feet away from you). (standard lab trash is
periodically monitored for radioactivity, and 32P is easy to detect; this
means that if radioactivity ends up there, there is a high likelihood that
you will get caught!).
- NEVER use the refrigerated
microcentrifuge for spinning radioactive samples—this is a
clean centrifuge. You may use
the non-refrigerated centrifuge, but it should be monitored
with a geiger counter AFTER EACH SPIN to ensure that there is no
surfaces must be cleaned IMMEDIATELY with warm water and soap, or else
they will remain hot for months or years.
- Discard all materials that have come in direct contact with radioactivty in the radioactive
waste. When in doubt, check
it with a geiger counter (which is never more than 2 feet away from you).
- FREQUENTLY (every 3-5 min.) check your gloves with
the (nearby) geiger counter to ensure they have not become
gloves must be discarded in the (nearby) radioactive waste immediately to
prevent cross-contamination of other surfaces.
- Everyone is responsible for monitoring his/her own
work areas after use of radioactivity. This should be done with a geiger counter with the
- 32P “requires” shielding when working with
this isotope, but keep in mind that this is particularly applicable to
high dose (as from the source vial).
Radiation emission falls off as the inverse square of the distance,
which means that if someone is working with radioactivity nearby without
shielding, you are NOT at significant risk. The other isotopes we use DO NOT require