Is it considered a triple double if one of the figures is 10 or more blocks in a game?

Yes. A player achieves a triple-double when he scores double-digits in 3 categories during one game. Points, assists and rebounds are most common, but it can also be blocks or steals.

When a player has a triple double that includes double digits in turnovers, it's called a "dirty" triple double and it makes me feel queasy just thinking about it.