Information Notice 1985-54, Teletherapy Unit Malfunction

Teletherapy Unit Malfunction

ML031180217
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, 05000000, Zimmer, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant, Skagit, Marble Hill, Barnwell
Issue date:	07/15/1985
From:	Partlow J NRC/OE
To:
References
IN-85-054, NUDOCS 8507110078
Download: ML031180217 (3)

SSINS No.: 6835 IN 85-54 UNITED STATES NUCLEAR REGULATORY

COMMISSION

OFFICE OF INSPECTION

AND ENFORCEMENT

WASHINGTON, D.C. 20555 July 15, 1985 IE INFORMATION

NOTICE NO. 85-54: TELETHERAPY

Addressees

All NRC licensees

authorized

to use teletherapy

units.

Purpose

This information

notice is intended to alert users of teletherapy

units of a recent incident involving

an Atomic Energy of Canada Limited (AECL) Theratron 60 unit. It is expected that licensees

will review the information

for applicability

to their facilities

and consider actions, if appropriate, to preclude a similar problem occurring

at their facilities.

However, suggestions

contained

in this information

notice do not constitute

NRC requirements;

there-fore, no specific action or written response is required.Description

of Circumstances:

A pressure regulator

switch (S15) on the pneumatic

system to an AECL Theratron 60 teletherapy

unit failed. As a result, the compressor

in the unit continued to run causing an overpressure

condition

in the holding tank. This condition prevented

the source drawer from immediately

closing on command.After treating a patient, the operator noticed that the compressor

kept running and that there was an unusual odor at the back of the machine. The machine was then turned off. The operator notified management, but no maintenance

was ordered at the time. When more patients arrived, the machine was turned back on and the treatments

continued.

After several patients had been treated, the teletherapy

unit failed to automatically

return its cobalt-60

sealed source to the shielded position.

The operator observed that the indicator

light on the radiation

monitor in the treatment

room remained on after the unit timer reached its zero setting. Attempts to turn off the unit by using the console controls failed. The operator immediately

removed the patient from the treatment

room.The pneumatically

operated source drawer independently

returned to the closed position approximately

an hour later.Discussion:

An AECL representative

has evaluated

the incident and has concluded

that this is an isolated incident resulting

from a failure to follow prescribed

maintenance

8507110078 IN 85-54 July 15 , 1985 procedures

on the unit. In this case, prompt emergency

response by licensee personnel

to remove the patient from the treatment

room after the failure rather than continue efforts to return the source to the "off" position avoided unnecessary

radiation

exposure.No specific action or written response is required by this information

notice.If you have any questions

regarding

this matter, please contact the Regional Administrator

of the appropriate

NRC regional office or this office.Jame G. Partlow, Director Division of Inspection

Programs Office of Inspection

and Enforcement

Technical

Contact: H. Karagiannis, IE (301) 492-9655 Attachment:

List of Recently Issued IE Information

Notices

---Attachment

1 IN 85-54 July 15, 1985 LIST OF RECENTLY ISSUED IE INFORMATION

NOTICES Information

Date of Notice No. Subject Issue Issued to 85-53 85-52 85-51 .85-50 Performance

Of NRC-Licensed

Individuals

While On Duty Errors In Dose Assessment

Computer Codes And Reporting Requirements

Under 10 CFR Part 21 Inadvertent

Loss Or Improper Actuation

Of Safety-Related

Equipment 7/12/85 7/10/85 7/10/85 Complete toss Of Main And 7/8/85 Auxiliary

Feedwater

At A PWR Designed By Babcock & Wilcox All power reactor facilities

holding an OL or CP All power reactor facilities

holding an OL or CP All power reactor.facilities

holding* an OLor CP Allpower reactor facilities

holding an.OL or CP All power reactor facilities

holding an OL or CP All power reactor facilities

holding an OL or CP, research, and test reactor, fuel cycle and Priority 1 material licensees 85-49 85-48 85-47 85-46 Relay Calibration

Problem Respirator

Users Notice: Defective

Self-Contained

Breathing

Apparatus

Air Cylinders Potential

Effect Of Line-Induced Vibration

On Certain Target Rock Solenoid-Operated

Valves Clarification

Of Several Aspects Of Removable

Radio-active Surface Contamination

Limits For Transport

Packages 7/1/85 6/19/85 6/18/85 6/10/85 All power reactor facilities

holding an OL or CP All power reactor facilities

holding an OL OL = Operating

License CP'= Construction

Permit