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Current NRC Regulations: General Rules
Secretarial space, hallways, and certain other areas of a department must qualify as an unrestricted area. The criteria for defining an unrestricted area are listed in 10CFR Part 20 Section 1301. Each licensee shall conduct operations so that:
POSTING OF RADIATION SAFETY RULES
According to 10CFR Part 20 Section 1208, a female technologist is legally considered a “declared pregnant worker” after she informs her employer in writing that she is pregnant and gives the estimated date of conception (2 required pieces of information).
MAXIMUM PERMISSIBLE ANNUAL DOSE TO AN OCCUPATIONALLY EXPOSED INDIVIDUAL
According to 10CFR Part 20 Section 1201a, which covers Occupational Dose Limits for Adults, the licensee shall control the occupational dose to individual adults to:
MAXIMUM PERMISSIBLE ANNUAL DOSE FOR JOB CHANGERS
According to 10CFR Part 20 Section 1201(f), the current Licensee shall reduce the dose that an individual may be allowed to receive in the current year by the amount of occupational dose received while employed by any other person or facility.
FREQUENCY OF INFORMING RADIATION WORKERS OF THEIR RADIATION EXPOSURE LEVELS
Although film badge readings are routinely posted on bulletin board on a monthly basis, every employer is responsible for informing each employee on an annual basis of his cumulative radiation dose. Posting readings on a monthly basis far exceeds this requirement.
DOSE CALIBRATOR CHECKS AFTER NORMAL WORKING HOURS
If a Nuclear Medicine Technologist performed requisite QC testing on the dose calibrator at 7:00 AM this morning and is then called in to perform a stat lung scan at 12:15 tomorrow morning, the elapsed time will be 17 hours and 15 minutes. Even though the elapsed time would be less than 24 hr, he would be required to repeat the constancy test on every setting that might be used that day. The day officially starts at 12:01 AM.
NEGATIVE PRESSURE TESTING IN ROOMS IN WHICH XE-133 GAS IS USED
In the past many of us have observed the NRC or State Inspector use a smoke gun
to blow a puff of smoke under the closed door in the room in which Xe-133
ventilation studies are performed. The purpose of this test is to ensure that
the room is under negative pressure with respect to the hallway. Therefore, our
expectation is that the puff of smoke will be drawn into the room. Inspectors
find failures occasionally when construction is underway and airflow is diverted
from Nuclear Medicine to another location, destroying the required pressure
differential. The test is no longer mentioned in the NRC Regulations and
therefore not mandatory.
THE ALARA POLICY
One of the policies that help to minimize radiation dose to Nuclear Medicine Technologists is called the ALARA Policy. ALARA is the acronym for “As Low As Reasonably Achievable”, that is, making every reasonable effort to maintain exposures to radiation as far below the dose limits as is practical consistent with the purpose for which the licensed activity is undertaken.
Like the ALARA Policy, the Radiation Safety Program must be included in written form in the department’s Policy and Procedure Manual. According to 10 CFR Part 20 Section.1101(c), each licensee shall periodically (at least annually) review the radiation protection program content and implementation. This annual review of the radiation safety program must be performed by either the Radiation Safety Officer or his designate (may be a consultant). RSO must inform management of review findings, which must be reviewed by Hospital Administration.
THE HOT SINK
One is permitted to designate one sink in the laboratory as a “HOT SINK” for disposal of low-activity radioactive waste. This waste must be readily soluble or readily dispersible biological material and each liquid waste disposal must be documented by the radioisotope, amount, date, and initials of person involved. Total annual quantity must not exceed 1 Ci for all isotopes for all users on one license.
PRESCRIBED DOSES / ADMINISTERED DOSES
The famous 10% rule is no longer valid in NRC states. By Federal law all DIAGNOSTIC doses must be within 20% of the prescribed dose. Many agreement states still require that all doses must be within 10% of the prescribed dose. In either case, if a technologist wishes to administer a dose higher than that prescribed, he must receive WRITTEN consent from the prescribing physician.
All therapeutic doses must be within 10% of the prescribed dose; a deviation of more than 10% constitutes a recordable event and a deviation of more than 20% constitutes a reportable event.
MONITORING THE THYROID OF I-131 DOSE ADMINISTRATORS
Historically when one administered a dose of I-131 to a patient with thyroid
cancer, one had to have his thyroid counted at 24-72 hr post admin time.
According to current NRC regulations, there is no requirement to perform thyroid
monitoring 24-72 hr after administration of oral I-131 sodium iodide. The
original regulation has been replaced with a vague statement about “timely
monitoring of the dose administrator”.
WHO IS AN ADULT ACCORDING TO THE US NRC?
According to the NRC, an adult is defined as an individual 18 or more years of
age
SIGNAGE FOR RADIATION AREAS
There are three designated areas:
LD50
and LD100
30
30
the whole body dose in humans where 100% of all
people die within 30 days. It has a
value of ~550 R; the LD50 whole body dose in humans where 50% of all
people die
30
within 30 days is ~350 R. With high-level medical intervention, the LD100
can be
30
increased to ~850 R.
MONITORING OF AN INDIVIDUAL WITH A FILM BADGE
According to 10 CFR Part 20 Section1502, monitoring is required if an individual is
There are three types of radioactive material licenses.
A SPECIFIC
license is issued to named persons for a specific use of radioactive materials,
for example a Nuclear Cardiology Imaging Center.
A GENERAL license is
issued to individuals who have very little chance of causing harm with the
materials, for example, a Radioimmunoassay Laboratory. This license also applies
to some laboratories and users of certain sealed sources.
A BROAD license is issued to universities and large medical centers for medical use of essentially any radioisotope.
GM SURVEY AND WIPE TEST OF LABORATORIES
A GM Survey of your lab must be performed on a daily basis in any room in which radioisotopes are used. A wipe test must be performed weekly, usually at the end of the week
For the GM Survey:
For the wipe test:
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All sealed sources (gamma counter calibration sources, dose calibrator standards, spot markers, etc) must be leak-tested every 6 months and results of this testing recorded in the appropriate logbook. If a source is found to be leaking radioactivity, it should be very carefully packed to prevent contamination and should be returned to the manufacturer for proper disposal.
36 of the 50 states have signed an agreement with the Nuclear Regulatory Commission (see map below) stipulating that they will be the sole regulators, but will follow Federal guidelines. They may choose to be more restrictive than the Federal guidelines, but not less restrictive. For example, in an NRC State, one can receive a high dose therapy with I-131 and be sent home; many Agreement States choose to be more restrictive and require hospitalization of the patient until his radiation level drops below 5 mR/hr at 1 meter from the patient’s chest.
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Each institution has only one Radioactive Materials license (RAM License),
regardless of the number of users of radioactivity on campus. The institution is
the licensee, not the director of Nuclear Medicine or the Director of Radiology
or the Radiation Safety Officer.
Hand monitoring
by Nuclear Medicine Technologists is required daily for most licensees.
Some technologists choose to monitor their hands after every patient or every
time they leave the laboratory. Treadmill monitoring is also required on
a daily basis. Results of these surveys must be recorded in an
appropriate logbook.
The following groups of people must undergo annual Radiation Safety Training:
Consider this scenario: an NRC Inspector has completed his inspection at 5 PM
and has his coat on, ready to leave. The only other person present is the one
leading the inspector on the department tour and he also has his coat on. On
impulse, the inspector walks over to the Hot Lab door, opens it, looks around,
and closes the door. He has discovered a citable offense. Since there are no
technologists or other personnel present and the room contained radioactive
materials, this is considered a breach of security. Anyone could have walked
into the room without being challenged and walked away with radioactive
materials.
OPENING PACKAGES CONTAINING RADIOACTIVE MATERIAL
According to 10 CFR Part 20 Section 1906, which deals with Procedures for Opening Packages, one should take possession of packages expeditiously (within 3 hours). Packages containing only gas e.g.., Xe-133) or special form radioactive material do not need to be monitored for contamination.
Every package containing radioisotopes must be logged in appropriately. This includes recording the radionuclide, product name, chemical form, physical form, and lot number; the time, date, and activity at time of calibration; the time, date, and activity at time of receipt; shipper's package identifying number, and initials of person receiving the package. In addition, if your license requires you to monitor every package received by your department, results of this monitoring must be recorded in this logbook.
Examples of packages that must be logged into the incoming package log book include
ACCEPTABLE METHODS OF WASTE DISPOSAL
According to 10 CFR Part 20 Section 2001, the authorized methods of disposal include
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