Information Notice 1994-26, Personnel Hazards and Other Problems from Smoldering Fire-Retardant Material in the Drywell of a Boiling-Water Reactor

Personnel Hazards and Other Problems from Smoldering Fire-Retardant Material in the Drywell of a Boiling-Water Reactor
	ML031060481
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	03/28/1994
From:	Grimes B; Office of Nuclear Reactor Regulation
To:	;
References
	IN-94-026, NUDOCS 9403220237
	Download: ML031060481 (8)
	v • d • e

- :~

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 March 28, 1994 NRC INFORMATION NOTICE 94-26: PERSONNEL HAZARDS AND OTHER PROBLEMS FROM

SMOLDERING FIRE-RETARDANT MATERIAL IN THE

DRYWELL OF A BOILING-WATER REACTOR

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 licensees to the potential for large amounts of thick, acrid

smoke to be produced from smoldering fire-retardant plastic sheeting. 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

On December 28, 1993, a fire occurred in the drywell of the Shoreham Nuclear

Power Station (Shoreham). Shoreham, a boiling-water reactor with a Mark II

containment, is currently undergoing decommissioning. The fire was caused by

hot slag that fell from the 137-foot elevation of the drywell where workers

were cutting a biological shield wall stabilizer support with an oxyacetylene

torch. The hot slag dropped through an opening in the biological shield wall

onto paper toweling and a coil of hemp rope at the 102-foot elevation, setting

them on fire. The burning rope subsequently dropped to the 78-foot level and

landed just below a temporary water collection system in the annulus space

between the lower portion of the reactor pressure vessel support pedestal and

the shield wall. The collection system was constructed of rope *and

fire-retardant plastic sheeting (Herculite and Griffolyn) and had been

installed to collect the runoff of potentially radioactive water expected from

cutting the shield wall. The burning rope made the plastic sheeting smolder, giving off a large quantity of thick, acrid smoke. Because of the smoke, it

was difficult for personnel in the area to breathe and to see in which

direction to go to leave the drywell.

Workers in the area saw the smoke and alerted the control room to a suspected

fire. The control room operators activated the plant fire brigade which

entered the drywell wearing self-contained breathing apparatus. However, the

fire brigade was unable to locate the source of the smoke because the dense

9403220237 k G 9P43R-

~ Al

IN 94-26 March 28, 1994

4-- smoke bl-ocke-d their vision. To help local £ecd the fire brigade asked

the control roomto place the reactor bu;; 1 vefntilation system on

standby 1-This action was not effective a -9rigade leader informed

the confolkreoom that the fire brigade col ide'--source of the smoke.

The control-room operators called the loks mr department to help

find and suppress the fire.

~ --

The plant.jfi-rebrigade made sure that all,; iwd been evacuated from

the area and again searched for the sourei pk'e.-The local fire

department entered the drywell to search;I ¢sand found some burnt

paper toweling and charred rope. About Vt ske in the drywell

began to .clear.-apparently because the cop nattial- feeding the fire

had been-consumed. No flames were observe ev'enht. The plant fire

brigade checked the area for ignition soul undnone. The licensee

suspended-work inside the drywell and coni iivesgate. The licensee

determined that the smoke had come from a- tely 5 5-square-meter

[60-sqUiare-foot]-section of the plastic s, V made'up the collection

trough$ii.'.';4 The licensee determined that the fire had; Sion equipment or

affected nuclear safety. However, 11 perk ~rtedto--the first aid

station suffering from smoke inhalation. : fnd the following

weaknesisesin industrial safety practicesi

Openings-in the biological shield wa 3beep covered to prevent

hot-slag from passing through.

Fire protection measures were not ad ood or were not

adequately specified in the fire pet

The fire permit did not clearly assi f t 'to check the area

for combustible materials before cut ,r -'-al support.

Workers-were not required to look fo l1hn'ges in the work

area,-,-such as the presence of combus vueable locations.

Discussi6n<-4.;cr

The plastic-sheeting materials involved in f-are commonly used at

many nuclear power stations. Although thi IY ire fire-retardant, they are-capable of generating large amoup n involved in or

exposed-to~a-fire condition. The total ai teila1 that was burned or

smoldered.at Shoreham was small; howeverX 11t'-e smoldering plastic

createdsi'gnificant hazards for personnel~ i£51ajnd made it

impossible for the fire brigade to locatet- X t~he smoke. Because of

the sm6ke, personnel in the drywell were'ii e7ij:-which direction to

go to exit-the drywell or to avoid the fig i]f he plant personnel

suffered smokedinhalation.

A_- a-4...a

-~ X.

IN 94-26 March 28, 1994 The Material Safety data Sheets for the Herculite and Griffolyn sheeting state

that those materials produce hydrogen chloride gas when burned and that self- contained breathing apparatus should be worn when attempting to extinguish

fires involving these materials. In addition to the hazard of smoke

inhalation, there is a potential for toxic side-effects from these fires.

Because these and similar plastic materials are routinely used at nuclear

facilities for contamination control, welding flash shields, and other

purposes, it is important to recognize that, if these materials are exposed to

or are involved in a fire, they generate a large quantity of smoke that

creates hazards for plant workers and may adversely affect plant operations or

fire-fighting efforts. These problems are exacerbated in confined spaces or

in areas with limited ventilation.

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 Office of Nuclear Reactor Regulation

(NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: R. L. Nimitz, RI

(215) 337-5267 F. L. Bower III, RI

(215) 337-5328 P. M. Madden, NRR

(301) 504-2854 Attachment:

List of Recently Issued NRC Information Notices

doA4-, PLJap 4 6.W

J

'- )itachment

IN 94-26 March 28, 1994 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

93-17, Safety Systems Response 03/25/94 All holders of Ols or CPs

Rev. 1 to Loss of Coolant and for nuclear power.

Loss of Offsite Power

94-25 Failure of Containment 03/25/94 All holders of OLs or CPs

Spray Header Valve to for nuclear power reactors.

Open due to Excessive

Pressure from Inertial

Effects of Water

94-24 Inadequate Maintenance 03/24/94 All holders of OLs or CPs

of Uninterruptible Power for nuclear power reactors.

Supplies and Inverters

94-23 Guidance to Hazardous, 03/25/94 All NRC Licensees.

Radioactive and Mixed

Waste Generators on the

Elements of a Waste

Minimization Program

94-22 Fire Endurance and 03/16/94 All holders of OLs or CPs

Ampacity Derating Test for nuclear power reactors.

Results for 3-Hour Fire- Rated Thermo-Lag 330-1 Fire Barriers

94-21 Regulatory Requirements 03/18/94 All fuel cycle and materials

when No Operations are licensees.

being Performed

94-20 Common-Cause Failures 03/17/94 All holders of OLs or CPs

due to Inadequate for nuclear power reactors.

Design Control and

Dedication

94-19 Emergency Diesel 03/16/94 All holders of OLs or CPs

Generator Vulnerability for nuclear power reactors.

to Failure from Cold

Fuel Oil

OL - Operating License

CP = Construction Permit