The dive op in Tobermory, Ontario wants 10 cold water dives over the past 18 months kr something like that, plus dives to a certain depth limit, and AOW to dive the Arabia (about 105ft deep to the sand). Bottom temp is low 40sF.In addition to asking for certification, the date of last dive and total number of dives.......most operators and shops up here in the PAC NW will also ask......."when was your last cold water dive"...