Firefighters generally know to stay away until the POCO arrives... but I've seen more stupid things from them than I can count.
There is one story of a department putting their ladder into 115kv. It totaled the truck, but luckily nobody was hurt. I assume there was nobody standing next to the truck. There was a guy on the ladder and a guy on the controls. The chief wanted the POCO to pay for a new truck because the wires were not covered.. I've never seen 115kv insulation in the overhead. How dare the utility not cover their transmission lines.
I had another where a substation feed riser was faulter, but was not operating the recloseing fast enough. The firefighter walks right over to the riser and then acts like I'm an idiot for telling him to stay away. Ten seconds later it catastrophically faulted. He would have been dead or burned really badly if it were ten seconds earlier.
And be weary of spacer cable, not that you would be near it, but it's only insulated for brush contact with high resistance objects(trees). I've seen it stay in and running when it's flipped and all the phases wrapped for months, but I've also seen it melt down from a twig across a phase and messenger.
I once had a tree crew clear spacer cable that was on the ground from downed trees. They put cones on it and told the people who lived at the house where it came down that it was safe to walk under it. The people had to duck to walk under it, it was about four feet off the ground. It was like that for two days.
