Can you use your hand in ping pong?

Yes; the ball can hit anywhere in the area below the wrist of your paddle-hand.

Also, sometime in 2011, they changed the rules to allow the ball to hit

that area TWICE, if it was accidental -- that is, as long as it's the same continuous stroke of the paddle -- and, the ball can never hit any place other than that area.

For example, if the ball deflects off your wrist AND THEN nicks/scrapes part of a finger, that's OK -- you just keep playing the point. However, if the ball

strikes any area above your wrist (of your paddle-hand), then you lose

that point (i.e. volley) -- and game then resumes as normal with the next serve for whoever is serving.

Another note on this: If you suspect your opponent of hitting the ball twice

outside the area mentioned above, then you should immediately call a "let"

and clarify what you saw and declare the point is yours. However, if your

opponent says it didn't happen that way, then you MUST call for a "referee" IF you do not accept the opponents' explanation of where/what the ball struck -- HOWEVER, usually you would ACCEPT your opponents' explanation, because table-tennis is a game among honorable players.

Joe Gervais (id=JoeG314) Nov. 13, 2009 (revised Nov. 12, 2011) (TT player in Saint Paul, Minnesota)