ML15303A504

UNITED STATES 

NUCLEAR REGULATORY COMMISSION 

OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS 

WASHINGTON, DC 20555-0001 

May 12, 2016 

NRC INFORMATION NOTICE 2016-06: URANIUM HEXAFLUORIDE CYLINDERS WITH 

POTENTIALLY DEFECTIVE 1-INCH VALVES 

 

ADDRESSEES 

All licensees authorized to possess and use source material or special nuclear material for the 

heating, emptying, filling, or shipping of uranium hexafluoride (UF6) in 30- and 48-inch cylinders. 

All holders of, and applicants for, a specific source material license under Title 10 of the Code of 

Federal Regulations (10 CFR) Part 40, “Domestic Licensing of Source Material.” 

All holders of, and applicants for, a fuel cycle facility license under 10 CFR Part 70, “Domestic 

Licensing of Special Nuclear Material.” 

Registered users of certificates of compliance for enriched (fissile) UF6 packages under 

10 CFR Part 71, “Packaging and Transportation of Radioactive Material.” 

Holders of Certificates of Compliance for enriched (fissile) UF6 packages under 10 CFR Part 71, 

“Packaging and Transportation of Radioactive Material.” 

All State Radiation Control Program Directors. 

U.S. Department of Transportation (DOT). 

U.S. Department of Energy. 

PURPOSE 

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to remind 

addressees, including more recent NRC licensees, of performance and safety concerns 

regarding UF6 cylinders with 1-inch valves manufactured by the Hunt Valve Company of Salem, 

OH. The NRC expects the recipients to review the information within this IN and consider 

actions, as appropriate, for cylinders in their possession or that they expect to receive. 

However, suggestions contained in this IN are not NRC requirements; therefore, no specific 

action or written response is required. 

DESCRIPTION OF CIRCUMSTANCES 

This section describes events involving transportation of cylinders fitted with Hunt valves that 

have occurred within the past 5 years: 
IN 2016-06 

Page 2 of 5 

• During 2014, as part of the shutdown of the Paducah Gaseous Diffusion Plant operated 

by the former United States Enrichment Corporation (USEC)1, four 48G cylinders 

containing natural UF6 were shipped to Honeywell. These cylinders were fitted with Hunt 

valves. Two of the cylinders were received and inspected by Honeywell and discovered 

to have Hunt valves installed. The other two cylinders were returned to USEC Paducah 

before they were received. 

• During late 2012 through early 2013, to support the Mixed Oxide Fuel Facility (MOX) 

project, MOX shipped eight 48G cylinders containing depleted UF6 to AREVA. Six of 

these cylinders were fitted with Hunt valves. Although shipment of depleted UF6 is not 

within the NRC’s purview, the NRC is concerned about the transportation of cylinders 

containing Hunt valves because these cylinders may be used in NRC-regulated 

activities. 

• During 2011, to support the Chinese AP1000 project, the China Nuclear Energy Industry 

Corporation sent five 30B cylinders containing enriched UF6 cylinders to Westinghouse 

Electric Company, Columbia Fuel Fabrication Facility (Westinghouse). These cylinders 

were fitted with Hunt valves. Westinghouse changed out the Hunt valves with 

acceptable cylinder valves. 

BACKGROUND 

Several provisions of the NRC’s regulations, license conditions, and certificates of compliance 

address the adequacy of equipment, facilities, and procedures to protect health and minimize 

danger to life or property. These include regulations in 10 CFR 70.23(a)(3) and (a)(4); 

10 CFR 71.43, “General Standards for All Packages”; and 10 CFR 71.85, “Preliminary 

Determinations.” These provisions also address the packaging and transportation of radioactive 

material. The manufacture, testing, and use of UF6 cylinder valves consistent with the 

provisions of the American National Standards Institute (ANSI) N14.1 standard, “Uranium 

Hexafluoride—Packaging for Transport,” provides an adequate level of assurance that the 

health and safety of the public and workers are protected, both for onsite operations and during 

transportation. The NRC has specified the use of the ANSI N14.1 standard through the NRC 

certificates of compliance for fissile UF6 transportation packages. The 10 CFR Part 71, 

“Packaging and Transportation of Radioactive Material,” regulation applies to any licensee 

authorized by a specific or general license to receive, possess, use, or transfer licensed 

material. The regulations in 10 CFR 71.5, “Transportation of Licensed Material,” invoke DOT 

requirements under 10 CFR Parts 107, 171 through 180, and 390 through 397. 

The DOT requirements at 49 CFR 173.420, “Uranium Hexafluoride (Fissile, Fissile Excepted, 

and Non-Fissile) require, in part, that packages containing UF6 be designed, fabricated, and 

inspected in accordance with the ANSI N14.1 standard in effect at the time the packaging was 

manufactured. Material used to manufacture cylinder valves must meet the material 

stress-relief specifications stated in ANSI N14.1. 

 

1 The NRC terminated USEC’s certificate of compliance for the Portsmouth Gaseous Diffusion Plant on 

October 12, 2011, and the certificate of compliance for the Paducah Gaseous Diffusion Plant on 

February 2, 2015, per USEC’s requests, after USEC decided to end NRC-regulated activities at those sites.
IN 2016-06 

Page 3 of 5 

In addition, Section 5.4.6, One-inch Valves-Defect of USEC-651, “The UF6 Manual, Good 

Handling Practices for Uranium Hexafluoride,” provides a listing of various manufacturers whose 

valves are considered unacceptable for use. The section further states that Hunt valves are not 

acceptable for shipment of cylinders that contain greater than a heel quantity of UF6. The intent 

is that the valve will be replaced before re-filling. 

NRC has previously identified performance and safety concerns with 1-inch valves for UF6

cylinders manufactured by Hunt. These safety concerns have been previously documented in 

the following: 

• NRC Inspection Report 99902011-2001-201, issued October 25, 2001, identified a 

number of significant deficiencies with Hunt’s compliance with quality assurance 

requirements. 

• NRC IN 2002-31, “Potentially Defective UF6 Cylinder Valves (1-Inch),” issued on 

October 31, 2002, discussed safety concerns related to UF6 cylinder valves 

manufactured by Hunt. Those safety concerns involved: (1) cracked packing nuts, and 

(2) the loss of material traceability and failure to conduct hardness testing, for a series of 

heat codes, for valve stems purchased by USEC.

• NRC IN 2002-31, Supplement 1, “Potentially Defective UF6 Cylinder Valves (1-Inch),” 

issued on March 24, 2003, discussed additional safety concerns related to UF6 cylinder 

valves manufactured by Hunt. USEC conducted a testing program, on a sample of 

valves, to demonstrate that the 1-inch UF6 Hunt valves would be able to perform their 

intended safety function. Because of those tests, several 1-inch valves manufactured by 

Hunt for UF6 cylinders failed the pressurized seat leakage acceptance criteria of the 

ANSI N14.1 standard. All failed valves were from Hunt valve Vendor Lot 200027-85. 

• NRC Bulletin 2003-03, “Potentially Defective 1-Inch Valves for Uranium Hexafluoride 

Cylinders,” was issued on August 29, 2003. 

• NRC Inspection Report 70-1113/2005-001, issued March 11, 2005, identified a notice of 

deviation for the failure to replace all Hunt valves on the cylinders owned by the 

licensee. 

DISCUSSION 

In 2003, the NRC issued Bulletin 2003-03 for the following reasons: 

• To advise addressees of the performance and safety concerns with 1-inch valves for 

UF6 cylinders manufactured by Hunt. 

• To request that action addressees take specific actions intended to identify potentially 

defective Hunt valves under their control. 
IN 2016-06 

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• To ensure cylinders with Hunt valves already installed were safely used and transported 

during a transition period. 

• To ensure that only valves verified to be compliant with NRC regulations, NRC licenses 

and certificates, and DOT regulations were in use by the end of a transition period. 

All action addressees were required to provide the NRC with a written response to the bulletin, 

detailing their plans to address their stock of Hunt valves and cylinders with Hunt valves. 

In accordance with the bulletin’s instructions, licensees submitted their plans, which were 

approved by the NRC as detailed in the following table. 

Table 1: Agencywide Documents Access and Management System (ADAMS) Accession 

Numbers for Licensee Responses to Bulletin 2003-03 and NRC Approvals 

Licensee Docket ADAMS Accession Nos. 

for Licensee 

Responses 

ADAMS Accession 

Nos. for 

NRC Approvals 

Framatome 

ANP, Inc. 

(Richland) 

07001257 ML032810214 ML040850633 

Global 

Nuclear Fuel - 

Americas, LLC 

(Wilmington) 

07000113 ML032720331 

ML15272A386 

ML032810007 

ML041030378 

Honeywell 

(Metropolis) 04003392 ML032751379 ML041890276 ML041030416 

USEC 

(Paducah, 

Portsmouth) 

07007001 

07007002 

ML032880118 

ML041560120 

ML051230301 

ML040770043 

ML041910540 

ML051370588 

Westinghouse 

Electric 

Company 

(Columbia) 

07001151 

ML032810122 ML041040537 

Nuclear Fuel 

Services, Inc. 

(Erwin) 

07000143 ML032720710 

No NRC response—

possessed no Hunt 

valves 
IN 2016-06 

Page 5 of 5 

In general, most licensees had a limited number of Hunt valves installed or in inventory, with the 

exception of USEC. Most of the approved plans in response to NRC Bulletin 2003-03 allowed 

use of the valves for purposes of storage, but required replacement of the valves before 

transportation. The events and circumstances previously highlighted in this IN demonstrate that 

some users of UF6 cylinders may lack awareness of the issue. Users of UF6 cylinders should 

consider the information outlined in the Background section of this IN with respect to cylinders 

they possess or may receive. 

CONTACT 

This IN requires no specific action or written response. Please direct any questions about this 

matter to the technical contact listed below. 

 /RA/ 

 Daniel S. Collins, Director 

 Division of Material, Safety, State, Tribal 

 and Rulemaking Programs 

 Office of Nuclear Material Safety 

 and Safeguards 

Technical Contact: John Vera, NMSS/DSFM 

 301-415-5790 

 Email: john.vera@nrc.gov 

Note: NRC generic communications may be found on the NRC public Web site, 

http://www.nrc.gov, under Electronic Reading Room/Document Collections. 
IN 2016-06 

Page 5 of 5 

In general, most licensees had a limited number of Hunt valves installed or in inventory, with the 

exception of USEC. Most of the approved plans in response to NRC Bulletin 2003-03 allowed 

use of the valves for purposes of storage, but required replacement of the valves before 

transportation. The events and circumstances previously highlighted in this IN demonstrate that 

some users of UF6 cylinders may lack awareness of the issue. Users of UF6 cylinders should 

consider the information outlined in the Background section of this IN with respect to cylinders 

they possess or may receive. 

CONTACT 

This IN requires no specific action or written response. Please direct any questions about this 

matter to the technical contact listed below. 

 /RA/ 

 Daniel S. Collins, Director 

 Division of Material, Safety, State, Tribal 

 and Rulemaking Programs 

 Office of Nuclear Material Safety 

 and Safeguards 

Technical Contact: John Vera, NMSS/DSFM 

 301-415-5790 

 Email: john.vera@nrc.gov 

Note: NRC generic communications may be found on the NRC public Web site, 

http://www.nrc.gov, under Electronic Reading Room/Document Collections. 

ADAMS Accession No.: ML15303A504 *concurred via email 

OFFICE NMSS/DSFM/SFLB NMSS/FCSE/ECB * NMSS/MSTR RII/DFFI/PB1 NMSS/FCSE/ECB

NAME JVera OSiurano AMcIntosh OLopez-Santiago TGrice 

DATE 09/29/2015 11/09/2015 09/30/2015 11/03/2015 11/09/2015 

OFFICE NMSS/DSFM/SFLB *TECH EDITOR NMSS/DSFM NMSS/FCSE NMSS/MSTR

NAME MSampson JDougherty MLombard CErlanger DCollins 

DATE 10/16/2015 3/14/2016 3/31/2016 3/28/2016 5/12/16 

OFFICIAL RECORD COPY