How many times must one pour water on the hands?[1]
One does not need to pour the water on the hands three times [as is required when washing upon awakening, rather a single wash suffices]. [Nevertheless the custom of the world is to be stringent, after certain actions[2], to wash three times inconsecutively, as will be explained in Halacha 4.]
[1] Admur Kama 4:18; M”A 4:17; Seder Hayom; Kneses Hagedola; Nimukeiy Orach Chaim 4:2
Other Opinions: Olas Tamid writes that possibly one is required to pour three times on his hand just like is required upon awakening in the morning. So rules also: Shlah Shaar Haosiyos 9; Lev Chaim 1:63; Kaf Hachaim [Falagi] 7:26; Ruach Chaim 4:3; Chesed Lealafim brought in Kaf Hachaim 4:61. The following Poskim rule that some actions require three times while others do not: Soles Belula 4:14; Machazik Bracha 4:6 in name of Makor Chaim; Elya Raba 4:12; P”M 4 A”A 17; Machatzis Hashekel 17; Ben Ish Chaiy Toldos 16-17; Kaf Hachaim 4:61 concludes that one who is stringent to wash three times after all the above actions is holy.
[2] These are leaving a cemetery; funeral; bathroom; marital relations. Some also wash three times after cutting nails