August 2013 on a charter (Florida Panhandle) 3 dive trip with dives to 102-114’ with 32% EAN. Buddy & I taking pics, being first in and last out on first two dives. On third dive we extended SI due to depth and nitrogen loading. On the way down we meet the spear fisherman that went down with short SI. We toured the wreck and started up anchor line thinking we were the last divers in the water. At 84’ we paused while I secured and stowed my camera. It was at this time we noticed a lone diver (spear fisherman that went down after us) below us with speargun speed swimming toward anchor line 15’ below us. Upon his arrival at the line he looked up, seen us, and bolted to us signaling out of air. At this point I still had 1700psi and was 2 minutes from deco. I immediately tried to give him my octo with 5’ hose but he had fixated on getting my buddies octo and was having trouble grabbing it. Once I got my octo within 6" of his face he took it and completed a safe reg exchange all the while his speargun had floated up between my legs. Before going any further I showed him my computer/air remaining and had him unload the speargun. We completed a 1 min stop at 50’ and 3 min at 20’ with me holding my octo hose to keep it from being stressed on my first stage (out of air diver was attempting to drag me to the surface by my octo hose). My buddy staying with us and monitoring the situation ready to intervene if necessary as he had only a few hundred psi less than I at the beginning of this event. When the out of air diver reached 3-5’ my buddy witnessed him toss my octo and bolt to the surface. He then attempted to climb the ladder on to the boat with his fins on. The dive master on the boat got him to remove his fins then he turned and fixated on me while I staying about 10’ away and waiting on him to get on the boat before approaching the ladder. After what seemed like several minutes he ask me (with the underwater OK signal) if I was ok. Now I was confused but returned an OK to him.
Nice that I regularly share air with my buddy to extend dive times which makes us both practice regulator exchange. We also continually discuss safety practices and how to minimize risks along with practicing skills on a regular basis.