BC Hydro was an early adopter of arc rated clothing for all arc flash exposed utility workers. This network system arc flash blew off a manhole cover (~90lbs/40kg).
Moving to flame resistant clothing stops clothing ignitons and dramatically reduces injuries. The second report says there are second and third degree burns and all workers are in the hospital.
It is likely in these events to have burns through arc rated clothing or ignition of underwear if the energy level is too high. Using blankets meeting ASTM F2676 can help prevent some injuries and arc rated clothing and other arc flash PPE can help prevent others. Reducing risk with safe electrical work procedures helps but if something you are near blows it can be very bad. Arc Flash Training helps workers understand the risks, NESC training is critical and often used by utilities in the US and in Canada.