United States Nuclear Regulatory Commission - Protecting People and the Environment

Gasket Defects

HPPOS-100 PDR-9111210221

See the memorandum from C. E. MacDonald to A. N. Fasano dated February 11, 1982.

This memo discusses requirements of 10 CFR 71.54 (c) which is now recodified as 71.87 (c). A gasket containing obvious imperfections is not "free from defects." Packages sealed with such a gasket do not meet the requirements of 10 CFR 71.87 (c).

A licensee contended that a gasket with a circumferential crack and a missing piece on the outer circumference was not defective. The licensee did not consider the gasket defective because the 3 to 4 inch-long crack in the gasket and the missing 1/4 by 1/4 by 1 inch-piece from the outer edge of the same gasket did not go through the full gasket radially. In addition, the licensee stated that criteria for defining a "defect" is not specified in 10 CFR Part 71 or the Certificate of Compliance. Also, the licensee referenced a definition of a defect found in 10 CFR Part 21.

Part 71 and the Certificate of Compliance do not provide an explicit definition of "defect." The definition of "defect" in 10 CFR 21.3 applies only to Part 21. The requirement in 10 CFR 71.54 (c) on routine determinations (prior to each use of the package) states: "The closure of the package and any sealing gaskets are present and are free from defects" (emphasis provided). The word "defect" is defined as "imperfection" in the dictionary.

It is NRC's opinion that when imperfections are obvious to the naked eye, a gasket is not free of defects (see, also, HPPOS-090).

Regulatory references: 10 CFR 71.87

Subject codes: 12.15, 12.17

Applicability: All

Page Last Reviewed/Updated Tuesday, June 09, 2015