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Interpretation Response #04-0047 ([Northrop Grumman Electronic] [Mr. Steven McKew])

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

Interpretation Response Details

Response Publish Date:

Company Name: Northrop Grumman Electronic

Individual Name: Mr. Steven McKew

Location State: NM Country: US

View the Interpretation Document

Response text:

Mar 30, 2004


Mr. Steven McKew                Reference No. 04-0047
Manger, Compliance Engineering
Northrop Grumman Electronic
P. 0. Box 746, Mail Stop 1401
Baltimore, NM 21203

Dear Mr. McKew:

This is in response to your letter dated February 25, 2004, concerning the requirements for measuring levels of radioactive contamination on the external surfaces of packages of radioactive material offered for transportation under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-181).

Section 173.443(a) requires the level of non-fixed (removable) radioactive contamination on the external surfaces of a package offered for transportation to be kept as low as reasonably achievable.  The HMR prohibit the non-fixed radiation contamination to exceed the limits set forth in Table 11 and authorize the use of a wipe survey or other assessment method to check for non-fixed radioactive contamination.  The use of wipes is a suggested technique; however, there is no specification for the type of instrument to be used to measure the amount of activity on the wipe.  The regulations permit other methods to be used to assure that contamination is within acceptable limits.  The HMR provide shippers considerable flexibility to determine the most appropriate method among recognized procedures to achieve the performance standard.

I hope this information is helpful.  Please contact us if you require additional assistance.


John A. Gale
Chief, Regulations Development
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.443 Contamination control