Contingency Planning: Alone and Adrift Down Current From the Dive Boat

Imagine that you're making a deep dive from a boat anchored more than 50 miles (80 km) offshore. The water is dark and cold and a stiff current strains the boat's mooring. You and your dive team enter the water and descend quickly to get below the chop. After four minutes of pulling yourself down the line the blackness parts to reveal the hull of the wreck. Conditions are marginal because of the strong current blowing across the wreck's narrow beam. You are cautious; one false move or slip up and you could be blown off the wreck. Suddenly your fears are realized when the piece of wreckage you are using as a hand hold breaks off. You are carried a scant 6 feet (2 meters) away, but you're unable to swim fast enough to get back on the wreck. You tire and stock kicking long before anyone in the team can tie off a line and assist you. Drifting through the blackness, you regain your composure, slow your breathing and set up your lift bag ascent line. Fighting back a growing fear of being adrift far out at sea, you hope the surface team is alert and that you won't be carried out of sight of the boat by the current while you ascend and decompress.

The possibility of being adrift at sea is one of the many hazards that divers must plan for. How it happens doesn't really matter; the results are the same whether you are blown off the dive site, the boat loses its mooring or sea conditions prevent the surface team from locating you. US Coast Guard data shows the real danger is the longer you are adrift the less likely you will be rescued. So it boils down to what types of equipment you can carry and what procedures you can use to increase the likelihood of being found QUICKLY.

The first and most important thing you can do is send your lift bag up as an ascent line. Even if other divers are aware that you're adrift it's going to be a while before they can notify surface support, unless they're using underwater comms. Getting your lift bag on the surface gives the topside crew the earliest possible warning of your predicament. If conditions permit, try tying the ascent line off to something in order to limit how far you drift, but don't count on that being an option.

While we're on the subject of lift bags, let's talk about color and size. If the topside support people can't see your bag because of sea or weather conditions, then color and size are unimportant. However, if conditions are fair, then you want to have a large brightly colored lift bag that will be easy to spot - even at a distance. I recommend a 100-pound bag as the minimum for surface stability and visibility. Mine is a nice bright yellow. I don't use a white bag because it's too easily missed when there are white caps on the waves.

After deploying your lift bag you can begin your ascent. Depending on what you were breathing, how deep you went and how long you stayed down, you could be "under the glass ceiling" for quite a while; of course you have the option of going for the surface immediately or making an abbreviated hang. That decision is yours to make. The complexities of that choice can't be adequately defined or second-guessed here, so we're going to continue our discussion assuming you're going to perform all required decompression stops.

While you're hanging under the lift bag you may have time to ponder what to expect once you're back on the surface. Think about the possibilities and be ready to deal with them once you're up. What if the boat is not in sight? How much boat or shipping traffic is in the area? How soon is nightfall? Although you may have adequate equipment for signaling for help and adequate exposure protection for lasting a day or two, you should prepare yourself for the psychological effects of being alone on the water and, in particular, alone at night.

After you surface, conserve your energy and body heat if nothing is in sight. Keep your lift bag on the surface. It may be spotted by a passing boat or aircraft. If a ship, boat or aircraft does pass nearby, always signal with the best means you have available. Even if the passerby can't stop or locate you directly, chances are if the authorities know you're missing, then the signal will be fowarded to some centralized search control point. The longer the authorities search without a signal or club, the greater the chance they will abandon the search, presuming you are lost.

Now let's discuss the equipment you should have brought in order to signal for assistance. A sonic alert device can grab the attention of a nearby boat. A whistle is a poor substitute, but is better than nothing. Sound-based signaling devices are fine for signaling surface craft over short distances, but are useless for long distances or when trying to signal search aircraft. An inflatable "safety sausage" topped with a metal-foil radar reflector is useful. One of your best bets is a couple of small boating flares packed in a waterproof container, such as an empty IKE Mini-C light. Flares are good for signaling aircraft or boats day and night. Another valuable piece of equipment is a waterproof personal strobe light, clipped to the low-pressure inflator hose on your BCD or harness. As an expedient, you can always use your dive lights to signal passing craft at night.

Hopefully the support team and crew aboard the boat are competent and alert. If they spot your lift bag they can dispatch a chase boat to monitor your hang and then pick you up. If they don't spot your bag and they realize you are overdue, then hopefully they'll notify the proper authorities so that a down current search and rescue operation can be mounted. But don't count on being that lucky. Always bring proper equipment for signaling.

Safe offshore boat diving, whether recreational or technical, involves good planning and the right safety equipment to cover all the major possibilities. Being adrift down current from the boat is probably the least planned-for problem an offshore diver can face. Make sure you stack the cards in your own favor as much as you can by taking the few extra pieces of equipment that might save your life.