Answer to Question #6271 Submitted to "Ask the Experts"

Q

In our hospital when a patient is scheduled for a stress myocardial SPECT study, the treadmill stress test is performed in the Cardiology Department and the patient gets the radionuclide (8-25 mCi ^99mTc-Tetrofosmin) injection while on the treadmill. Then he/she is taken by a wheelchair to the Nuclear Medicine Department for the SPECT study.

We have recently been inspected by the Joint Commission International which suggested that a radiation survey of the stress room should be carried out after the patient has been injected.

As a radiation safety officer, I am not aware of this recommendation. Further, I could not find any supporting evidence for this claim, especially that all inpatients who do not require dynamic studies get their radionuclide injection in their rooms, that is, nuclear medicine technologists take the dose in a shielded box to the patient's room, give the injection, then the patient comes to nuclear medicine sometime later as required by the procedure.

In our policy, a radiation survey is required for the therapy patient's room as well as daily survey for nuclear medicine department and the hot laboratory. Do you think that the inspectors' recommendation is justifiable and therefore we should do the radiation survey of the stress room after each patient?

A

All the following information can be found in the Nuclear Regulatory Commission's (NRC) NUREG on this issue, NUREG-1556 Vol. 9 Rev. 1, "Consolidated Guidance About Material Licenses - Program-Specific Guidance About Medical Use Licenses." (Please also see it on the Web site.)

Appropriate survey requirements are based on the requirements of 10 CFR 20.1301 (that the total effective dose equivalent [TEDE] to an individual member of the public from the licensed operation does not exceed 1 mSv [0.1 rem] in a year and that the dose in any unrestricted area from external sources does not exceed 0.02 mSv [0.002 rem] in any one hour).

Surveys are required when it is reasonable under the circumstances to evaluate a radiological hazard and when necessary for the licensee to comply with the appropriate regulations.

The frequency of routine surveys depends on the nature, quantity, and use of radioactive materials, as well as the specific protective facilities, equipment, and procedures that are designed to protect workers and the public from external and internal exposure. Frequencies acceptable by the NRC are the following:

• Survey at the end of each day of use all radiopharmaceutical elution, preparation, assay, and administration areas (except patient rooms, which will be surveyed at the end of the therapy instead of on the day of administration) when using radiopharmaceuticals requiring a written directive (for example, all therapy dosages and any ¹³¹I dosage exceeding 30 μCi).
• Survey monthly all laboratory areas where only small quantities of gamma-emitting radioactive material are used (< 200 μCi at a time).
• Survey weekly all radionuclide use, storage, and waste storage areas. If diagnostic administrations are occasionally made in patients' rooms (for example, bone scan injections, ^99mTc heart agents) and special care is taken to remove all paraphernalia, those rooms need not be surveyed.

All the above has the caveat that the licensees must follow all other federal, state, and local requirements, requirements in their license, and any commitments made in their license application.

Joe DeCicco, CHP, and
Cynthia Jones, PhD