On several occasions, a 40KV high voltage capacitor would break down internally. Each contained an overpressure "blow plug" and weighed about 200 pounds. When one breaks down, it creates a small explosion, the "blow plug" ruptures, the sidewalls bulge out and PCB is spewed out covering a large area.
It would take about a day for the repair center and transmitter personnel to clean up the mess it caused. Everything (corona rings, insulators, nearby capacitors and the floor) had to be cleaned thoroughly with soap and water. All cleaning rags were bagged and shipped to a hazardous waste disposal facility in Monel, NY where it was incinerated at 2000 degrees (F or C, can't remember which).