Question: How many Jokers can a player use in an exposure?

Answer: A player may use as many jokers as needed to call (claim) a tile needed to complete a pung, kong, quint, or sextet. A player should use Jokers wisely and consider factors such as but not limited to being in the beginning, middle, or end game. Using all of one’s Jokers to call for an exposure early in the game might leave you unable to call other needed tiles as they are discarded. However, using of all of your Jokers when you are close to or “set” for Mah Jong, would make sense.  

Source:  Mah Jongg Made Easy (2020 page 7 para. 1, page 22 #2, page 23 #10, page 30, para. 6)