I have always assumed that mentioning to adults "follow safety measures at all times" is somewhat condescending. Until one power supply blew up a few centimetres from my face. I was lucky that I did not get seriously hurt. But I have been in a laser lab where a technician did not use proper goggles and lost one of her eyes permanently.
So, use extra caution when working, building, or modifying a power supply to fit your exact project.