I assess the risk based on the circumstances, for personal injury, fire and ruining finishes with abrasive dust.
Try and grind outward from a building not showering anything I deem valuable, like a vehicle. Drives me carazy how many people blast all kinds of things with their grinders.
Simple Googles and Hearing proetection for PPE.
MOSTLY, and I have removed all grinder sheilds, is keeping track of the direction of a spinning disk, considering it may fail at any time. Had a ZIP disk fail (used inappropriatately) at a friends and the violence of it, surprised me.