I learnt these lessons all the hard way over 40 years of using an angle grinder. You most often see You tube videos where they operate a cutting disc without a guard and I cringe!! The manufacturers provide a stout guard for a purpose. The one issue that is not shown is when using the grinder without a guard and the proximity of your soft knuckles to the grinding blade, which I have unfortunately tested on a couple of occasions. Sometimes it is very tempting to operate it without a guard because it gets in the way - DON'T! Also, wear PPE. I've had grind spatter embed itself in my eyeball and then had to have it drilled out at the eye clinic A&E - not pleasant!
Need more useful safety videos out there. Like not wearing gloves with certain tools. I watch my mother cut her thumb on a table saw. Would have just been a small knick if her gloves didn't catch the blade.
