Review of Recent Laser Incidents at DOE facilities. Joanna Casson Los Alamos National Laboratory

Transcription

1 Review of Recent Laser Incidents at DOE facilities Joanna Casson Los Alamos National Laboratory 8 th Annual DOE Laser Safety Officer Workshop SLAC September 12, 2012 LA-UR Slide 1

2 Overview Laser-related Incidents 5 Lesson Learned Reports 17 ORPS Reports 9 different DOE sites 2 Incidents resulted in injuries Slide 2

3 ORPS Reports: Number of Occurrences Laser Occurrences Slide 3

4 ORPS Reports by Laser Classification Laser Classification Unknown 2 6 Class Class 1 (4 embedded Class 4) 1 Class 1 Class 2 Class 3R Class 3B Class 4 Unknown Class 3B Class 3R Slide 4

5 Occurrences by Site incidents: SLAC, SNL-ABQ 2 incidents: INL, LANL, LBNL, NTS 1 incident: ANL, LLNL, Pantex SLAC, SNL-ABQ LANL, NTS, LBNL, INL ANL, LLNL, Pantex Slide 5

6 Two Laser Injuries SLAC Retinal Burn to eye-class 3B laser INL Burn to finger-class 4 laser Slide 6

7 9 Incidents in 2009 LLNL HeNe laser arcing between metal laser casing and metal bracket LANL Interlock system did not operate as expected. Idaho Small fire from a Class 4 laser used to cut steel. SNL-ABQ (3) All intentional defeat of interlock system NTS Fiber optic cable left attached during laser alignment SLAC Injury to worker due to misalignment of optics Argonne Communication fiber cut Slide 7

8 1 Incident in 2010 LBNL Electrician entered laser lab without supervision using code he had observed previously. Wore appropriate eyewear. Slide 8

9 4 Incidents in 2011 Pantex Laser beam unexpectedly discharged. LBNL Technician entered unlocked room when laser was on. Warning lights not working. INL Beam was unexpectedly on during maintenance/alignment. SLAC Class 1 enclosure was not intact. Slide 9

10 3 Incidents in 2012 LANL Laser unexpectedly fired due to wrong class of laser and model being set by manufacturer. SLAC Laser worker entered NHZ without putting on eyewear. NTS Triggering one laser inadvertently causes other lasers to trigger due to electronic configuration. Slide 10

11 Lesson Learned Reports: LANL-2009 Interlock failure Tech failed to engage interlock Exterior light remained green 2 nd tech noticed laser was operating, but light was still green and paused alignment work No injuries SLAC 2009 ORPS report filed Injury to worker Slide 11

12 Lesson Learned Reports: 2011 Pantex 2011 Charged capacitor shorted on a Pulse Laser control cabinet Technician wearing appropriate PPE De-energize and ground capacitor before attaching measurement equipment INL 2011 Will be discussed in detail at a later talk Do not perform tasks from memory Ensure that workers understand the safety controls Ensure workers understand in what modes the laser beam is exposed Ensure workers have had the appropriate training SLAC 2011 Class 1 enclosure was removed for maintenance and not replaced No signage to indicate that enclosure was not intact Since he thought it was in Class 1 mode, he was not wearing PPE Graduate student turned on laser and noticed beam on shirtsleeve No injury to worker Slide 12

13 LANL incident May 2012 Occurred on May 7, 2012 Involved 30 Watt Laser Marking Technologies Nd:YAG laser Class 1 enclosure with a magnetic interlock Upgrading the laptop used to control the laser Software upgraded as well Original laptop had failed on March 13, Slide 13

14 Laser setup Laser Slide 14

15 LANL incident May 2012 No intent to operate the laser during laptop exchange Power to the laser was on Goal was to verify interface between laser and laptop Written instructions provided by vendor Not covered by work control documentation Workers knowledgeable about the laser operations and the IWD covering normal operations IWD required eyewear only during interlock check Pre-job brief conducted Laser normally fires when software button is engaged. Slide 15

16 LANL incident May 2012 Replaced laptop Turned on laser power Turned on laser and opened software Opened laser enclosure Adjusted height of mounting stand Heard laser on mounting stand Shut door Put on eyewear Reopened door and determined laser still firing Shut door Notified management Locked and tagged out laser Slide 16

17 LANL incident May 2012 Workers taken to Occupational Medicine for evaluation Referred to ophthalmologist May 8, ophthalmologist determined no eye damage Workers determined to be outside the NHZ of the laser Diffuse NHZ- 9 cm Workers 1 and 2 feet away Laser fires without user input with wrong settings Laser Power <2 W On Class 1 mode setting Laser operates as expected on Class 1 mode and correct model Slide 17

18 Summary No obvious trend to number of yearly laser incidents No obvious pattern to the DOE site where accidents occurred Class 4 lasers contribute to the most number of incidents Slide 18