In the past, bunkers have been treated like art at a museum: DO NOT TOUCH.
For the 2019 Rules of Golf, there are still some touch restrictions, but “incidental” touches aren’t penalized.
Starting this season, a player is allowed to touch/remove any loose impediments in a bunker (no longer just by local rule), and is generally allowed to touch the sand away from the ball with a hand or club in ways that won’t affect play.
But common-sensibly, there are still three instances where the sand of a bunker still cannot be touched:
– during a practice swing (bunkers would never have any sand in them if this was allowed);
– by grounding the club right in front of or behind the ball; or
– in making the backswing for the stroke itself.
As long as you aren’t intending to test the sand, go ahead and touch the bunker with your hand or club.
Go ahead and pick up any loose impediments in the bunker.
But don’t touch the sand around the ball just before or during the stroke itself…