Summary of Los Alamos TA-53 Arc-Flash Event John Anderson Jr. 13 August 2015

Overview  Event Synopsis  Arc Flash Reconstruction  Analysis - People, Processes, and Human Factors  Slides and text are edited from: –TA-53 Arc-Flash Accident Joint Accident Investigation Team (JAIT) Report –Energy Facility Contractors Group (EFCOG) Electrical Safety Task Group (ESTG) Meeting July 13, 2015, Livermore, CA. John E. Anderson Jr.| Department Heads Meeting - 13 August

Arc Flash Event Synopsis  On Saturday May 2, 2015, maintenance personnel at Los Alamos National Laboratory (LANL) were conducting both a two-year circuit breaker preventative maintenance (PM) and five-year substation cleaning PM on equipment that powers the LANSCE facility area.  Some elements of the maintenance were done Saturday evening, after which two of the three buses in the switchgear were re-energized to support equipment and systems.  On Sunday morning, May 3, 2015, work resumed on the last bus, which remained isolated from Saturday.  A crew member entered a cubicle on the wrong side of the clearance tag that contained only instrumentation with bus bars passing through. There was no visual or physical indication of power such as status lights. John E. Anderson Jr.| Department Heads Meeting - 13 August

Arc Flash Event Synopsis  Based on physical evidence, spraying cleaning solution used to clean the bus bars created an electrical breakdown between the 13.8-kV bus and the grounded cubicle wall, resulting in an arc-flash and blast.  The resulting blast ejected the wireman from the cubicle, resulting in significant burns to the hands, wrists, face, neck, and torso, and a head injury as he fell backward and struck test equipment positioned on the floor outside of the cubicle.  Nine individuals were transported by emergency vehicles to the Los Alamos Medical Center (a local hospital) as the result of the arc-flash.  One individual (E1) was identified as critical and transferred to the Albuquerque Medical Center Burn Center at the University of New Mexico Hospital in Albuquerque via CareFlight.  Five individuals were evaluated and released, two were treated and released, and one (E2) remained hospitalized for further observation before being released two days later. John E. Anderson Jr.| Department Heads Meeting - 13 August

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Accident Scene Slide 5

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Arc Flash Damage in Cubicle 17 Slide 6

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Victim Impact Slide 7

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Clothing Slide 8

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Bus A Work Area Slide 9

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Clearance Point Established Saturday Slide 10 Accident, no tape found on #17 Clearance Tag Informal completion tracking Blue=Clean Red=Breaker Tested

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Cubicle 17 from West Side, Yellow Tape Slide 11

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Event Analysis – System Configuration Slide 12

Event Analysis - People  Crew composed of journeyman linemen, switchgear electricians, a switchgear apprentice (familiar with 13.8 kV+ work), and wiremen electricians (familiar with 600 V- work). All were current in training on electrical safety.  The methods for indicating zero-energy work areas for linemen and switchgear electricians are different from wiremen (clearance tags vs lock and tag (LOTO)).  Inconsistent zero energy verification on job – some felt lineman isolation (clearance) was the zero energy verification. At least one worker checked cubicles before working inside.  The maintenance crew was under the supervision of a journeyman lineman because the switchgear is inside a utility fence line with exclusive access. John E. Anderson Jr.| Department Heads Meeting - 13 August

Event Analysis - Procedures  The two standing work orders for switchgear maintenance (cubicle cleaning and circuit breaker servicing) were familiar to most on the crew.  According to the foreman and others, these maintenance tasks were worked separately in the past.  For the work on Saturday, all power was removed from the switchgear. Sunday’s work occurred with two out of three busses energized. Significantly changing the work environment hazards.  No “meeting of the minds” discussion was held between managers and crew to consider compensating controls for partially energized equipment or concurrent tasks.  This resulted in: –Uncertainty of zero voltage checks required for each cubicle, –No consideration for Look-Alike Equipment, and –Inadequate consideration of work flow during concurrent tasks. John E. Anderson Jr.| Department Heads Meeting - 13 August

Event Analysis – Human Factors  The aisle in which the work was performed, which was not particularly generous in size to begin with, was crowded, with concurrent work activities (cleaning and breaker testing). Nine workers with equipment and breakers in a 40’ isle.  The open door on the energized cubicle went unnoticed by others for 5-10 minutes before the arc-flash occurred.  Red and blue electrical tapes were used to marked cubicles that had their breakers serviced and cubicles cleaned, but work progress and tasks were not otherwise monitored.  The accident scene cube had been cleaned on Saturday, but not marked with blue tape.  A restricted area for hi-pot testing of the breakers was marked by yellow plastic caution tapes across the aisle. John E. Anderson Jr.| Department Heads Meeting - 13 August

Event Analysis – Human Factors  The clearance tag and one strip of caution tape were one cubicle apart, with the accident scene cubicle in-between. The caution tape would have been a much more visually apparent barrier than the clearance tag.  Yellow Caution Tape between cubicle 16 and 17 and no completion (blue) tape on cubicle 17 to indicate cleaning completed – two potentially misleading visual cues that cubicle 17 was within the remaining work scope.  No designated tasks assigned or formal method to track work completion opened the door to error. John E. Anderson Jr.| Department Heads Meeting - 13 August

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Questions? Slide 17

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Event Analysis – Bus Layout, Cubicle 17 Slide 18 Phase B Phase C Phase A

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Event Analysis – Phase C, Cubicle 17 Slide 19 Phase C Grounded Wall First Arc C-G Steel Angle Melted Arc Termination moves due to thermal and magnetic forces

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Event Analysis – Phase B, Cubicle 17 Slide 20 Second Arc B-G Phase B Phase C

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Event Analysis – Phase B&A, Cubicle 17 Slide 21 Third Arc B-A Phase A Phase B

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA Unclassified Event Analysis – Phase B&A, Cubicle 17 Slide 22 Phase A Second Arc B-G Steel Angle Melted B-A Arc Path Phase B Phase C Third Arc B-A