Monday, June 11, 2018

Safe Scuba Diving Entries and Exits Part II: Exiting the Water

In part one of our two-part series on scuba diving entries and exits, we looked at how to make a safe entry and some common methods for doing so. A safe exit from the water is just as important, whether it's back onto a boat or the shore. As always, it's vital to attend the dive briefing for information specific to the site. That said, here we'll look at some common ways of exiting the water and how to avoid pitfalls.

General dive exit advice

  • If you're about to dive in a new region, research diving procedures in the area. The entry and exit techniques will help you decide what equipment configuration to use and, sometimes, which accessories to bring with you on the dive or leave topside.
  • Listen to the briefing. Always. Whatever the diving situation. The local guides will explain all the procedures for exiting the water.

Boat exits

Larger vessel: returning to an anchored boat 

In some circumstances, the diving vessel may remain static and groups may dive from and return to the anchored vessel. There may be regional variations in this case. In the Red Sea, for example, divers sometimes surface next to the reef and then pull themselves, hand over hand, back to the stern along a mooring line. Divers may also ascend the vessel's anchor line and then make their way alongside the vessel's hull using the descent line to the exit point. In other instances, a trail or mermaid line will be in the water behind the boat with a float at the end. Whatever the variations, there are some common pieces of good practice:

  • Do not ascend under the boat or traverse the underside of the boat's hull to make your way back to the ascent point. Stay clear of the vessel's propeller. If there is an emergency and the captain must immediately start the engine, up-anchor and move the vessel, they must be sure no one is underneath the boat.
  • Ascend with your buddies in clear view where the boat crew can see you if possible. Don't ascend directly under the vessel's ladder or exit point. The exit point is also often also the entry point — another diver in a later group may be about to enter the water and unwittingly giant stride onto you. Ideally, ascend around 10 to 13 feet (3 to 4 m) from the exit point where you're unlikely to bump the boat's hull or be a hazard to divers entering the water. As always, establish positive buoyancy.
  • Retain your mask and air source. There are numerous reasons to do so:
    • Most obviously, especially in choppy conditions, you'll need it to protect your vision and airway from splashing water.
    • You can look beneath the surface on final approach to the boat, identifying any hazards and grasping the ladder in surge or waves.
    • You won't fumble to remove equipment and accessories because you can see clearly beneath the surface to unclip and remove weight systems and fins.
    • It allows you to be ready to deal with any emergency situations, from a dropped fin to a distressed buddy.
    • Your mask protects your airway from any fumes that may be emanating from the vessel's engine or generators as you make your final approach at water level.
  • Approach the exit point one-by-one as directed by the dive leader or crew. Don't go to the bottom of the vessel's ladder until the preceding diver is clear in case they slip and land on top of you.
  • Once it's your turn to exit, keep contact with the boat's ladder. Remove those items of equipment instructed in the briefing, such as weights or even your complete scuba unit. If you're taking your gear off entirely, remember to remove your weights from your BCD pockets first. Keep a point of contact with the vessel during this process so that you don't drift away without fins.
  • Using peaks and lulls in the waves' movement to your advantage, begin to climb the ladder with your mask on and air source in (if you're still wearing your gear). Retain three points of contact with the ladder at all times. The crew will often be there to steady you.
  • When safely back on the dive deck and clear of the water, remove your mask and air source and thank the crew. Identify your fins, weights and anything else you may have removed in order to exit the water and take them to your station. This keeps the dive deck clear of trip hazards for subsequent divers exiting the water.

Larger vessel: 

On smaller diving vessels or liveaboards, the main vessel, as opposed to a zodiac or dinghy, will pick you up. Surfacing with your DSMB in open water for pick-up by a large vessel shares many of the same recommendations outlined above.

  • Know your vessel. There may be several operating in busy regions. It's not unheard of for inattentive divers to board the wrong boat in error.
  • Sometimes individual boat captains have specific signals to differentiate you from other divers surfacing in the area. You might hold your DSMB a certain way or flash a specific hand signal. These are outlined in the briefing.
  • Stay close. Sometimes it's tricky for boat captains to spot divers floating on the surface, especially with other boats around. Pay particular attention to your vessel as makes its final approach. Make sure your mask is on and you have an air source in your mouth. Stay behind the dive guide with the DSMB if you don't have your own. The captain is looking for the marker buoy, not individual divers.
  • Don't swim toward the boat. Stay still unless instructed. Divers will sometimes even form a conga line, linking up in a chain behind the dive leader. This makes the boat captain's job much easier, as he can position the boat best for pick up without worrying that a rogue diver has inattentively floated into the boat's path.
  • As the boat turns to expose the exit point, be ready to make your final approach. In the case of a liveaboard vessel with a platform, the crew will often throw a trail line with a buoy or ball attached. Be ready to grasp it and then pass it to the diver behind you in the group.
  • Begin to pull yourself hand-over-hand along the line toward the back of the boat. With your mask on and your air source in you'll be able to approach face down, seeing the boat and ladder proximity.
  • As you near the dive platform, pause 10 feet (3 m) from the boat and look up for any final instructions from the crew. For example, there may be two ladders and they may usher you to one or the other.
  • Make your final approach one at a time as recommended in the previous example. If it's not your turn, stay on the line a couple of feet clear of the boat until it's your turn. Don't cling to the back of the boat, especially in a larger surge.

Dinghy pick-up

Zodiacs or dinghies are quite common on liveaboards and at drift-dive sites. While many recommendations overlap, there are key differences.

  • Never approach the zodiac by passing the propeller.
  • Hold the side of the zodiac with one hand while removing your equipment with the other and passing it up to the crew. This could include large accessories like cameras, your weights or your entire scuba unit.
  • Retain your fins, mask and snorkel (when applicable).
  • When instructed, find a rhythm of bouncing with the waves and then kick, fin and pull yourself onto the zodiac's hull, rolling into the center of the boat. Then remove your fins and mask.
  • Once on board, help balance the zodiac by perching on the side of the hull as instructed so the next diver can enter the boat.

Shore diving

If you're exiting to a beach or making a relatively shallow shore exit:

  • Plan your exit route before you dive. Note compass bearings and landmarks above and below the surface. Build a reserve into your gas supply for the final approach.
  • Unless there is large surge or surf, most shore exits happen mostly beneath the waves. Approach the beach or shore swimming beneath the surface, negatively buoyant, until you can comfortably stand up.
  • Surface, roll and plant your fins firmly on the bottom. Assess the wave height and rhythm. If there is significant water movement, keep in close contact with your buddy and help each other remove fins. Support each other when required to avoid losing your footing and drifting back into deeper water or losing balance.
  • If the water movement is minimal, either look down and reach down — or lie on your back — and remove your fins before planting your feet on the bottom again. Lean on your buddy for more support if necessary.
  • As always, retain your mask and air source and calmly walk out of the water, carrying your fins until you're clear in case you slip or trip.
  • If the water movement picks up you can, as a last resort, crawl to the beach or shore on your hands and knees until it's safe to sit and remove your equipment. This is less elegant and not good for your knees or exposure suit but, sometimes, required.

The recommendations above won't cover every situation, but you can apply them in many circumstances. Safe exits are a key part of diving. The dive isn't over until you're back on firm ground and de-kitted. Remember your basic training. Listen to the briefings. Take advice and have a safe day diving.

The post Safe Scuba Diving Entries and Exits Part II: Exiting the Water appeared first on Scuba Diver Life.



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