United States Nuclear Regulatory Commission - Protecting People and the Environment

U.S. Nuclear Regulatory Commission

Gasket Defects

HPPOS-100 PDR-9111210221

Title: Gasket Defects

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

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 Thursday, March 29, 2012