When cutting sandstone with a 9" angle grinder and a breaker, do not allow the grinder to skip, grab your building glove and drag the back of your hand into the rotating disc, slicing it open and severing tendons. Unless you want to be off work in a cast for 8 weeks or more, unable to renovate your house, ride a bike, drive a car or get the tops off Marmite pots.
Regards
Richard