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76

Information Notice No. 93­76: Inadequate Control of Paint and

Cleaners for Safety­Related Equipment

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555

September 21, 1993

NRC INFORMATION NOTICE 93‐76: INADEQUATE CONTROL OF PAINT AND CLEANERS FOR

SAFETY‐RELATED EQUIPMENT

Addressees

All holders of operating licenses or construction permits for nuclear power

reactors.

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information

notice to alert addressees to recent plant events during which safety‐related

plant equipment was rendered inoperable because of inadequate material

control. It is expected that recipients will review the information for

applicability to their facilities and consider actions, as appropriate, to

avoid similar problems. However, suggestions contained in this information

notice are not NRC requirements; therefore, no specific action or written

response is required.

Description of Circumstances

Inoperable Emergency Diesel Generator Caused by Painting

On December 29‐30, 1992, while South Texas Project, Unit 1 was in hot

shutdown, Houston Lighting and Power Company (the licensee) repainted

emergency diesel generator "C". The diesel generator remained in service

during the painting evolution and no post‐maintenance test of the engine was

performed to verify operability. The work request for the painting of the

emergency diesel generators includes a requirement for a post‐maintenance test

after painting of the equipment. The post‐maintenance test requirement was

deleted by a system engineer who decided that a post‐maintenance test was not

necessary because the diesel was not declared inoperable. On

January 20, 1993, while Unit 1 was at 95 percent power, emergency diesel

generator "C" failed to start during a surveillance test. The licensee

determined that paint in the metering rod guides for the injectors had locked

up the fuel racks, preventing the diesel generator from attaining the rated

speed during the surveillance test. The areas were cleaned and maintenance

personnel cycled the fuel rack linkage to ensure the racks moved freely in

both directions. The emergency diesel generator was satisfactorily tested and

returned to service on January 22, 1993. The licensee had last successfully

tested this diesel generator on December 24, 1992, before it was repainted.
Between December 29, 1992, and January 20, 1993, the licensee (1) changed

operating modes three times, (2) experienced several instances of cross train

9309150262.

IN 93‐76

September 21, 1993

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equipment being out of service for a time greater than that allowed by the

limiting condition for operation with this emergency diesel generator

inoperable, and (3) experienced one instance of another diesel generator being

inoperable for a time greater than allowed by the limiting condition for

operation for two diesels out of service.

Emergency diesel generator "C" was the first of the diesel generators to be

painted. The licensee has implemented precautions to be taken to assure that

diesel generators are operable following painting evolutions.

Inoperable Diesel Generator Caused by the Use of Unapproved Cleaner

On January 6, 1992, while the main generator at Brunswick Steam Electric

Plant, Unit 2, was being taken off line, Carolina Power and Light Company (the

licensee) found that a main turbine stop valve limit switch had failed,

causing an inadvertent electrical lock‐out. The lock‐out initiated an

automatic start signal to all four emergency diesel generators; however,

emergency diesel generator 2 failed to start. The licensee initiated a quick

start signal and observed that all components functioned normally except that

the fuel control racks did not move.

The licensee removed and inspected the fuel control racks and found that the

metering rods on the left bank fuel control racks were extremely dry and were

sticking, the metering rods on the right bank fuel control racks contained

coagulated lubricant, and both fuel control racks were covered by a very thin

white residue. The licensee analyzed this residue and determined it was from

the Planisol‐M used to clean the emergency diesel generator. This residue and

the loss of lubrication on the fuel control linkage prevented the fuel control

racks from moving and caused the emergency diesel generator to fail to start.

The licensee implemented a procedure which requires that the Planisol‐M

residue be removed from all surfaces and that the equipment be properly

lubricated after it is cleaned before it is declared operable.

Inoperable Switches Caused by the Use of Unapproved Cleaner

On October 25, 1992, while the Waterford Steam Electric Station was in cold

shutdown, an operator used a commercial contact cleaner to clean engineered

safeguards control panel CP‐8. The cleaner used was SWISH, a product

manufactured by Chemsearch. SWISH is normally used for coin‐operated vending

machines and electronic equipment, and is not approved for use on the control

panels. Within approximately 2 hours, the cleaner solvent caused the plastic

parts of 16 safety‐related control switches to bond together, making the

switches inoperable. The inoperable switches affected various engineering

safety features equipment, including suction valves from the refueling water

storage pool, a high‐pressure safety injection pump, and flow control valves

for low pressure cold‐leg injection. The licensee issued a standing

instruction to identify the only approved cleaner to be used on the control

panels..

IN 93‐76

September 21, 1993

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Discussion

These events are examples of deficiencies in the control of materials and

processes used on safety‐related equipment. Appendix B to 10 CFR Part 50

establishes quality assurance requirements for safety‐related equipment at

nuclear power plants. The pertinent requirements of Appendix B apply to all

activities affecting the safety‐related functions of equipment including

cleaning and painting. The events described above demonstrate that even

apparently benign actions such as cleaning and painting may have consequences

that are detrimental to safety, and that personnel are not always adequately

aware of the potential effects of such actions on the safety functions of

safety‐related equipment.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project managers.

/s/'d by AEChaffee/for

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Eric J. Benner, NRR

(301) 504‐1171

Attachment:

List of Recently Issued NRC Information Notices

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