While diving off the coast of Oahu our group got caught in some kind of under current and visibility went from 80+ft to 20ft in about a minute. The dive master got seperated from the group and we ended up serching for him. We looked for about 5 min (staying within arms reach of eachother) then surfaced. In that short period of time we had been swept a good distance apart and had to signal the boat to pick us up. After getting aboard we found out the dive master had to signal for pick up as well becasue he was swept in a different direction. Lucky for us everone kept their cool and relied on their training...except for the one minute part. Long story short I’ll always stick to the one minute rule because things can change very quickly.