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Interpretation Response #06-0153 ([Air Force Medical Operations Agency] [Mr. Mark C. Wrobel ])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Air Force Medical Operations Agency

Individual Name: Mr. Mark C. Wrobel 

Location State: DC Country: US

View the Interpretation Document

Response text:

Sep 5, 2006


Mr. Mark C. Wrobel                 Reference No. 06-0513
Chief, Radiation Protection Division
   Secretariat, Air Force Radioisotope Committee
Air Force Medical Operations Agency
   Office of the Surgeon General
110 Luke Avenue, Room 405
Boiling AFB, DC 20032-7050

Dear Mr. Wrobel:

This is in response to your letter dated June 12, 2006, requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) pertaining to the contamination control requirements for Class 7 (radioactive) materials under § 173.443. Specifically, you ask for a wipe test waiver to be granted to the U.S. Air Force for Chemical Agent Monitors (CAMs), Improved Chemical Agent Monitors (ICAMs), and Automatic Chemical Agent Detector Alarms (ACADAs). You have also referenced and enclosed a letter of interpretation from Hattie Mitchell to Vernon Vonders (Ref. No.: 99-0119) that. clarified § 173,443 in regards to the degree of flexibility of contamination control.

Section 173.443 states that “The level of non-fixed radioactive contamination may not exceed the limits set forth in Table 9 and must be determined by either:

(1) Wiping an area of 300 square centimeters of the surface concerned ...; or
(2) Alternatively, the level of non-fixed radioactive contamination may be determined by using other methods of equal or greater efficiency.”

Sections 173.44 3(a)(1) and 173.443(a)(2) continue to allow a shipper the same 1 of flexibility. The shipper must either make one or more wipe measurements and compare the results against the limits in Table 9, or use another method of equal or greater efficiency. As used in § 173.443(a)(2), “efficiency” represents the ratio of a measured value of contamination (such as from a wipe) divided by the actual contamination on the surface of the package, or, in a more general sense, an alternate method which gives the same or greater assurance that the package contamination levels do not exceed the stated regulatory limits. If a shipper utilizes methods which do not rely on actual wipe samples, such as new packaging material which is protected from on-site contamination, ii; is acceptable as long as it ensures compliance.


I hope this information is helpful. Should you have further questions, please contact us.



Charles E. Betts
Senior Transportation Specialist
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.443 Contamination control