The Use of P-32 in the Laboratory
1. Data
2. Monitoring
3. Facilities
4. Concerns
5. Waste
Half-life (T½) = 14.3 days Personnel dosimeter badges
will be issued to all personnel working in laboratories where P-32 is
utilized. TLD finger type extremity monitors will be issued to all personnel
handling P-32. Appropriate survey instrumentation
will be required of all laboratories working with P-32. (A geiger counter
sensitive to beta particles) A tiny drop of contamination of P-32 can
be easily detected with a geiger counter. This survey instrumentation
must be calibrated on an annual basis. Annual calibration is handled
by the Safety Department. After each use of P-32 in
the laboratory, the work area must be surveyed with an appropriate survey
instrument to detect any areas of contamination. Check your hands, shoes,
clothing, work bench, floor, and laboratory equipment. These surveys
need not be logged unless your laboratory is instructed to do so by
the Radiation Safety Officer. All P-32 should be stored and used behind
a beta shield consisting of low density material (i.e., 3/8"-1/2"
plexiglas/lucite) When more than one millicurie of P-32 is handled, a sufficient number of
x-rays (bremmstrahlung) may be formed to require Lead foil to be added to the exterior of
the shield. In most cases, the manufacturer's supplied shield is sufficient for stock
vials stored in a refrigerator/freezer. Designate a specific area of the
laboratory for P-32 handling. Place the plexiglas shield near a wall (not toward another
work area on the other side of the bench) away from the main flow of traffic in the
laboratory. A series of dry runs must be conducted
with all new uses or procedures of P-32 in order to preclude unexpected complications. No individual research laboratory will be
permitted to exceed a possession of 10 mCi of P-32. This level will assist in maintaining
exposure levels that are as low as reasonably achievable. Eye protection must be worn
by all personnel handling greater than 10 mCi of P-32. Surface radiation exposure
to the skin of the hands is a concern. Use remote handling tools, such
as tongs, to reduce doses to the hands. A drop of contamination containing
1 microcurie of P-32 on 1 cm2 area of the skin produces an exposure
of 2,000 millirems per hour. This means that the quarterly NRC limit of 7500 millirems
to the skin would be reached in 3 hours and 15 minutes. Radiation exposure in air
over an open vial is a concern. The dose rate at the opening of a vial
containing 1 millicurie of P-32 can be as high as 26,000 millirems per
hour. This means that the quarterly NRC limit of 18,250 millirems
for the hands would be reached in 42 minutes. Using lower concentrations
is very desirable. Most companies will provide lower concentrations
if requested. The cost of using pre-labeled materials or lower concentrations
is higher but the return in safety more than offsets the cost. Change gloves frequently,
and monitor gloves frequently, during the use of P-32 . Wash your hands
thoroughly after using P-32. Plexiglass containers are
recommended for P-32 radioactive waste. All P-32 waste must be transferred
from each research area to the storage area as soon as possible to prevent
any unnecessary exposure. Therefore, call the McNeil Science & Technology
Center or the Griffith Hall Stockroom (X3141 or X8843) when the waste
is ready for a pick-up. (See Radioactive Waste Procedures) Check the normal trash container to make
sure no radioactive waste has been accidentally placed there.
Maximum Beta energy = 1710 KeV (100%)
Maximum range of Beta in air = 20ft.
Maximum range in tissue = 8mm
Percent transmitted through the dead layer of the skin = 95%.
Critical Organ = Bone for transportable compounds. Lung and lower intestine are critical
organs for inhalation and ingestion.
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University
of the Sciences in Philadelphia • 600 South Forty-third Street
• Philadelphia, PA 19104-4495 • phone: 215-596-8800 • email:
safety@usp.edu