Back before I retired, I was attending a safety tyraining class at the plant training center There was a brilliant white flash similar to the descriptions I've heard of nuclear explosions, almost concurrently with a very loud ZZZZZBOOM!. All of the lights went out. We walked to the front door to see what was happening. The high winds that day 50mph or more had somehow caused two 4160 lines to cross phase. I went back inside and called the plant emergency brigade. All they could do when they arrived was to keep everyone away from the area and await the power company trucks.It shut the plant down. I got some pretty good OT that night, standing by to restart the plant. When I left at midnight, the power company was just restoring power, so the next technician got all of the real work.