The dive boat I work on has "instructs" all divers to put fins on before standing and take fins off before climbing. Our rental fins are full foot and all but one guide wear full foot so there are trips where no one could loop straps over wrists. 
Luckily; we dive multiple Islands, there is usually a side that is calm, we would never take tourist divers in rough seas. Sometimes there is chop and sometimes there is current but there is a line behind the boat to hold on to. It is better to cancel on days where seas are rough; no puking, no unhappy divers because it wasn't pretty, no injuries.

Luckily; we dive multiple Islands, there is usually a side that is calm, we would never take tourist divers in rough seas. Sometimes there is chop and sometimes there is current but there is a line behind the boat to hold on to. It is better to cancel on days where seas are rough; no puking, no unhappy divers because it wasn't pretty, no injuries.
