The story of a dive
The diving work starts with the preparation of all the equipment, the boat and of course, the weather and sea conditions must be good. Here in the top set of pictures a team briefing is underway where the proposed work is outlined to the dive teams. Usually the divers are divided into to two teams and after the briefing, the divers are kitted up with a Dresser assisting them, the equipment double checked then finally the divers are away.
Once the divers leave the vessel they work together to get to the bottom, they have a down line from the boat known as a "shot" secured to the wreck this enables them to get straight to the site and back again to the boat without being carried away by the tide. The visibility underwater can vary from none at all up to thirty feet, but these good conditions are very rare. In most cases, the divers work in poor visibility and have to work by touch. The wreck site has guide lines secured around it to help the teams getting around and doing their work in poor visibility, and of course for getting back to the shot.
While working on the wreck, the divers here are in contact with the Dive Superintendent by means of hard wired communications, donated by the National Geographic Society. The Superintendent controls the times that the divers are in the water and logs their actions. Finally when the dive is completed, the divers start to ascend, but in order to purge the nitrogen from their blood, they hold on to the shot as a set depth and for a set time to decompress. Nitrogen is absorbed in the blood below a certain depth and is the cause of the "bends" that can be disabling and the cause of death. When they have decompressed, they are recovered safely back on board where the work of dismantling, cleaning and stowing the equipment takes place prior of recharging the air cylinders. The cylinders are recharged in land in a clean and safe environment.