United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 91-25: Commercial-Grade Structural Framing Components Supplied as Nuclear Safety-Related Equipment

                                UNITED STATES
                        NUCLEAR REGULATORY COMMISSION
                    OFFICE OF NUCLEAR REACTOR REGULATION
                           WASHINGTON, D.C.  20555

                                April 1, 1991


Information Notice No. 91-25:  COMMERCIAL-GRADE STRUCTURAL FRAMING 
                                   COMPONENTS SUPPLIED AS NUCLEAR 
                                   SAFETY-RELATED EQUIPMENT


Addressees:

All holders of operating licenses or construction permits for nuclear power 
reactors.

Purpose:

This information notice is intended to alert licensees to problems in the 
dedication of structural framing components supplied to the nuclear industry 
by the Unistrut Corporation (UC), Wayne, Michigan.  It is expected that 
recipients will review this information for applicability to their 
facilities and consider actions, as appropriate, to avoid similar problems.  
However, suggestions contained in this information notice do not constitute 
NRC requirements; therefore, no specific action or written response is 
required.

Description of Circumstances:

The most common structural framing components supplied to licensees by UC 
are 1-5/8-inch wide, continuously slotted, structural framing channel 
members; fasteners; and mechanical accessories such as channel nuts, 
fittings, and pipe clamps.  These components are supplied through a network 
of nationwide Authorized Service Centers, some of which are owned and 
operated by UC.

The NRC inspected the UC facilities and records and found that UC had failed 
to implement measures to control the dedication of commercial-grade 
structural framing components.  UC supplied Certificates of Conformances 
(COCs) stating that these materials met the requirements of Appendix B to 
Part 50 of Title 10 of the Code of Federal Regulations (10 CFR) and were 
supplied in accordance with the provisions of 10 CFR Part 21.  UC failed to 
demonstrate that it had:  (1) established an adequate basis for accepting 
material certifications from its suppliers of fasteners and coil material, 
(2) verified the chemical and physical properties of coil material, (3) 
performed destructive product testing traceable to each coil of material 
used to manufacture structural framing channel, (4) maintained traceability 
of the material used to manufacture mechanical accessories, or (5) performed 
adequate product testing on all mechanical accessories.

UC manufactures structural framing channel members from coil material 
procured to UC's material specifications from various commercial-grade 
suppliers and manufacturers.  These suppliers provided material 
certifications that UC 

9103270304 
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                                                            April 1, 1991 
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accepted without assuring that the coil materials could be traced and 
identified to the certifications.  UC did not perform a destructive product 
test on structural framing channel that was traceable to each heat or lot of 
coil material.  Furthermore, UC did not perform tests or examinations to 
ensure the accuracy of the chemical and physical properties listed in the 
material certifications.  UC supplied the commercial-grade structural 
framing channel to licensees as safety-related components that comply with 
the requirements of the American Society for Testing and Materials (ASTM) 
Standards, Appendix B to 10 CFR Part 50, and 10 CFR Part 21 with COCs 
stating that these requirements were met, even though UC did not perform an 
adequate commercial-grade dedication of the coil material.  In some 
instances, UC also certified that the channel met the requirements of the 
American Society of Mechanical Engineers, Boiler and Pressure Vessel Code 
(ASME Code), Section III, Class 2, Subsection NF-2600 but did not 
demonstrate compliance with the ASME Code requirements.

All fasteners supplied by UC were procured as commercial-grade items from a 
single supplier (General Fastener Company of Livonia, Michigan), which 
furnished machine screws, nuts, and washers that were 1/2-inch and smaller.  
UC procured these fasteners according to the Society of Automotive Engineers 
(SAE) Standards and supplied them to licensees as safety-related fasteners 
that comply with the requirements of the ASTM Standards, Appendix B to 
10 CFR Part 50, and 10 CFR Part 21 with COCs stating these requirements were 
met, even though UC did not perform any commercial-grade dedication 
activities.

Mechanical accessories are also manufactured by UC from coil material 
procured to UC's material specifications from various commercial-grade 
suppliers and manufacturers.  These suppliers provided material 
certifications that UC accepted without assuring that the coil materials 
could be traced and identified to the certifications.  Channel nuts and 
90-degree angle fittings are the only mechanical accessories that receive 
product tests.  UC also did not perform tests or examinations to ensure the 
accuracy of the chemical and physical properties listed in the material 
certifications.  UC supplied the mechanical accessories to licensees as 
safety-related components that comply with the requirements of ASTM 
Standards, Appendix B to 10 CFR Part 50, and 10 CFR Part 21 with COCs 
stating these requirements were met, even though UC did not perform an 
adequate commercial-grade dedication of the coil material.

Licensees have conducted numerous audits of UC and some have  placed UC on 
their approved vendor lists to supply safety-related components.  The 
inspectors examined sample audit conclusions and found that they varied 
widely.  Some licensees found that UC was fully capable of supplying 
safety-related components that comply with the requirements of Appendix B to 
10 CFR Part 50 and 10 CFR Part 21, and in one instance found that UC could 
supply safety-related components that comply with the ASME Code 
requirements.  Other licensees found that UC could only supply 
commercial-grade components.  In performing many of the audits, licensees 
did not identify UC's failure to implement adequate measures to control the 
dedication of commercial-grade structural framing components, indicating a 
significant weakness in the performance of these audits.
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Discussion:

UC manufactures structural framing components used to support nonsafety and 
safety-related components such as pipes, instrument lines, ducts, cable 
trays, and conduits.  The NRC has not identified a significant safety 
concern or in-service failure regarding the known applications of these 
structural framing components.  However, structural framing components were 
supplied by UC as safety-related and may be installed in safety-related 
structures, systems, or components and may not meet quality standards 
commensurate with the importance of the safety function to be performed.  
Therefore, licensees may wish to review their use of structural framing 
components to confirm that the procured equipment is acceptable.  In 
addition, licensees may wish to examine the adequacy of applicable audits 
and their audit process.

This information notice requires no specific action or written response.  If 
you have any questions about this matter, please contact one of the 
technical contacts listed below or the appropriate NRR project manager.




                                  Charles E. Rossi, Director
                                  Division of Operational Events Assessment
                                  Office of Nuclear Reactor Regulation


Technical Contacts:  Steven M. Matthews, NRR
                     (301) 492-3191

                     Stewart L. Magruder, NRR
                     (301) 492-3220


Attachment:  List of Recently Issued NRC Information Notices 
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