Information Notice No. 90-20: Personnel Injuries Resulting From Improper Operation of Radwaste Incinerators

                                UNITED STATES
                           WASHINGTON, D.C. 20555

                               March 22, 1990

                                   IMPROPER OPERATION OF RADWASTE 


All U.S. Nuclear Regulatory Commission licensees who process or incinerate 
radioactive waste.


This information notice is intended to inform recipients of recent 
industrial accidents involving the operation of radioactive waste 
incinerators.  It is expected that licensees will review this information, 
distribute the notice to responsible safety staff and equipment operators, 
and consider actions, as appropriate, to preclude similar accidents from 
occurring at their facilities.  However, suggestions contained in this 
notice do not constitute new NRC requirements, and no written response is 

Description of Circumstances:

Two uranium fuel fabrication facilities have reported personnel injuries, 
resulting in the accidental amputation of fingers, involving the operation 
of radioactive waste incinerators.  A description of each of the accidents 
is provided in Attachment 1, and were reported to the Occupational Safety 
and Health Administration (OSHA) by NRC.  In summary, the accidents ap-
parently involved: 

  o  Unauthorized removal of a safety shield
  o  Failure to follow proper procedures
  o  Operator error
  o  Component failure
  o  Poor safety design
  o  Inadequate sorting of waste products

The accidents did not directly involve radiation safety hazards.  However, 
any serious personnel injury in the vicinity of radioactive material has the 
potential to escalate to a situation which could result in a radiation 


Serious personnel injuries can occur when personnel ignore or circumvent 
safety systems and equipment.  To help prevent such injury, it is important 


                                                           IN 90-20 
                                                           March 22, 1990 
                                                           Page 2 of 2 

that personnel strictly adhere to procedures and operating parameters.  It 
is also important that maintenance and safety inspectors routinely observe 
the operation of equipment and be alert to unauthorized modifications, un-
safe operating conditions and practices, and equipment malfunctions. 

When unsafe conditions and practices are noted, it is imperative that unsafe 
operations be halted, corrective action taken to resolve the problem, and 
employees advised of the conditions and corrective actions.  Merely 
correcting an unsafe practice and condition without also advising the 
affected workforce does not advance the safety goal of eliminating 

No specific action or written response is required by this information 
notice.  If you have any questions about this matter, please contact the 
technical contact listed below or the appropriate regional office.

                             Richard E. Cunningham, Director
                             Division of Industrial and 
                               Medical Nuclear Safety
                             Office of Nuclear Material Safety
                               and Safeguards

Technical Contacts:  Cynthia Perny, Region II
                     (404) 331-5559

                     Charles Hooker, Region V
                     (415) 943-3784

1.  Description of Events
2.  List of Recently Issued NMSS Information Notices
3.  List of Recently Issued NRC Information Notices

                                                             Attachment 1       
                                                             IN 90-20
                                                             March 22, 1990
                                                             Page 1 of 2

                            DESCRIPTION OF EVENTS

Note:  The following descriptions are based on reports from licensee 
personnel.  They are for informational purposes to illustrate the importance 
of following proper safety procedures.  The Nuclear Regulatory Commission 
makes no representation as to the accuracy of the specific details of the 
reports.  The licensees also reported these events to OSHA field offices. 

Advanced Nuclear Fuels Corporation, Richland, WA.

On September 29, l989, an employee was filling a drum with ash from a 
uranium-contaminated waste incinerator.  The employee lowered the drum to 
check the ash level, but could not get the lift to raise the drum back up.  
The worker placed his right hand on the lip of the drum and then reached 
around the drum to jiggle the rear limit switch (this switch tells the 
controller that the drum is in the proper location).  As the worker reached 
around the drum, the lift activated and lifted the drum to the cooling 
chamber discharge port gasket lip.  This crushed and severed the tip of the 
right middle finger above the first joint. 

The worker reacted by reaching behind him to activate the emergency-off 
control.  This did not lower the drum.  The worker then pulled the emergency 
off control again, which turned the system on again, and hit the down 
control to release the lift.  The lift still did not lower the drum.  At 
this point, the worker began moving his trapped hand and was able to free 
it.  Immediately after the hand was freed, the lift activated and the drum 
was lowered.  Further amputation was required at a hospital, due to the 
extent of damage to the finger.  No radioactive contamination was found in 
or around the wound. 

The licensee's investigation identified the cause of the accident as the 
failure of the upper limit switch which controls raising of the scissors 
lift.  The switch failed in the upper or closed position.  The controller 
believed that the drum was in the up position when, in fact, the worker had 
lowered it to look inside the drum.  When the worker reached inside the hood 
to jiggle the rear limit switch, the upper limit switch activated (opened) 
and the lift actuated, lifting the drum.

Follow-up actions by the licensee included:

o   Fabrication of a position guide to center drums under the cooling 
    chamber discharge port 

o   Installation of proximity switches on the access doors of the cooling 
    chamber discharge port hood, to disable the lifting sequence when the 
    doors are opened

o   Installation of a second emergency stop button on the hood (new 

                                                             Attachment 1 
                                                             IN 90-20
                                                             March 22, 1990
                                                             Page 2 of 2

o   Installation of handles on the drums, to eliminate the need for 
    personnel to place their hands on the drum lip

o   Engineering review of replacement of upper limit switch with a hydraulic 
    pressure control system
o   Engineering review of lift with lift vendor, to determine if the speed 
    of the scissors lift could be decreased

General Electric Co., Wilmington, N.C.

On October, 4, l989, an employee was attempting to clear a blockage in a 
uranium-contaminated waste incinerator ash discharge chute, when the 
horizontal discharge slide activated and severed two fingers on her left 
hand below the nail.  The employee had removed a plexiglass cover from the 
front of the discharge chute and reached up the chute to dislodge banding 
material.  At the same time, the employee's right hand was on the hydraulic 
control lever for the horizontal discharge slide.  The slide is a metal 
plate that closes the chute opening prior to the discharge chamber being 

The employee had activated the hydraulic start button for the discharge 
station pump. The employee then removed the plexiglass cover and with her 
right hand pushed the discharge control lever.  When the employee reached up 
the chute with her left hand to dislodge some blockage, her right hand slid 
off the slide control lever, enabling the slide to close and sever her 

Slight contamination was detected on the finger ends.  Based on follow-up 
bioassay information, no internal exposure to uranium is believed to have 

Follow-up actions by the licensee have included:
o    Conversion of the hydraulic ash discharge slide system to a manual 

o    Retraining for incinerator operators

o    Revision of procedural instructions on ash clean-out

o    Installation of a new plexiglass cover for discharge enclosure

o    Provision of special tools for clearing choke-ups

o    Review and analysis of waste going to the incinerator.  Reemphasizing 
     to waste-sorting personnel the importance of separating combustibles 
     from non-combustibles.

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