A skipper's point of view
DO YOU REALISE how close to invisible you are out at sea With just your head and shoulders above the surface, you become a microscopic speck in an endless expanse of water. You may well be able to see distant boats, even people on their decks, but will they be able to see you
I would suggest that it’s highly unlikely.
In the May edition of DIVER, I put together an overview of hi-tech solutions for locating divers lost or adrift at the surface. EPIRBs, PLBs and submersible marine radios are all excellent solutions.
I invested in a McMurdo Fastfind EPIRB/PLB after researching the May article, and would highly recommend that all divers carry such a unit. I can no longer imagine a situation in which I would get into the water without it.
However, this device I would reserve for a worst-case scenario. I would much rather be tracked and located visually using lo-tech kit, and never find myself in a situation in which I would need to activate the EPIRB/PLB.
Twelve years ago, a major report on surface marker aids for divers was carried out for the Health & Safety Executive by Heriot-Watt University, and reported in DIVER (Can Anybody See Me February 2000).
The research took into account the reports of divers from clubs around the UK, and included practical tests carried out at sea in various conditions. It proved that we divers need to maximise our visibility and hence our chances of being located while at the surface.
Little has changed today. Divers worldwide still get into the water without planning for the possibility of surfacing away from their boats.
Divers still rely on skippers and boat-crews to spot their distant heads and shoulders, and divers still get lost.
So just what can we do to make ourselves more visible at the surface
I RECENTLY SPENT A DAY aboard Weymouth dive charter boat Skin-Deeper with its iconic owner, skipper and RNLI cox’n Ian Taylor.
My objective was to experience dives from the skipper’s point of view, to see for myself what it’s like to track divers on the surface and perhaps pick up a few tips and tricks that would help me be safer and more visible in the water.
Out with Ian were members of Dacorum Sub Aqua Club, a Hemel Hempstead-based group of technical divers enjoying a warm-up weekend, knocking the cobwebs off their kit and preparing for a busy dive season.
They planned to dive the Moidart (Wreck Tour 144, December 2010).
I have been diving from Ian’s boats for nearly 10 years, carrying out deep technical dives as well as those within the recognised recreational limits.
I hold him and his boat-handling skills in very high regard, and I chose him because I know he “does it right”.
Ian is also an accomplished commercial diver with a huge amount of technical experience. In 2004, we dived together as safety divers for a film crew making a 60-year anniversary documentary on the wreck of the Allied Landing ship LST 507, torpedoed and sunk by a German E-boat in 1944.
As both technical diver and skipper, Ian knows what he needs to see to find his divers in the water, what works and what doesn’t. He does it day-in, day-out throughout the year, in every conceivable sea state.
I asked him what he considered the best surface location aid. “A good-sized, self-sealing delayed surface marker buoy,” he replied without hesitation.
“I can track divers before they surface and be on station when they do”.
AND HOW IMPORTANT WAS COLOUR I wondered, aware that the Heriot-Watt research had concluded that yellow was the optimal colour.
“I find an all-yellow marker difficult to spot at sea level in all but ideal lighting,” said Ian.
“Bright red or orange markers are better. They can be seen from a long way off in nearly all conditions”.
I pointed out that SAR helicopter pilots and crew considered yellow easier to see from the air.
“Yes, but in my opinion if a diver had a red DSMB he’d be on my boat drinking tea, instead of waiting in the water for the winch-man,” said Ian.
“For me, the red and yellow split-colour buoys are the best solution. They’re more visible over a whole range of conditions, especially if they feature some black to create contrast.”
Also important in Ian’s opinion was for the diver’s initials to be marked in big black letters on the top half of the marker for contrast.
“That makes it even easier to see,” he says. “The late Keith Morris used to use black duct tape, and it worked a treat.
I can also track individuals and plot their positions by name.”
Ian has some rules that he likes to be followed; he explains them at the time of booking, so that there’s no confusion.
The most important is this: “Nobody gets into the water without a DSMB and reel. If they’re going deeper than 50m, they must take two. To me, a spare buoy and reel is more important than any other spare kit you might need,” says Ian.
One diver per SMB is the rule. “If I’ve got 12 divers in the water, I need to see a minimum of 12 buoys.
“If a diver suffers a tangle on the reel during deployment and has to let go, that buoy will just lie flat on the surface. When a diver’s hanging onto his reel, the buoy will stand upright.
“As long as I can see that all my divers are on buoys, I’m a happy man.”
“I like the divers all to bag-off [deploy their buoys] at the same stage of their dives. Just before leaving the seabed or wreck is my preference; that way, I can track them as a group.
“If one diver fails to deploy, I would assume that he or she had gotten into trouble, and I would take the appropriate emergency measures.
“It’s good to talk; I like my divers to tell me their plans for the dive,” says Ian. “If some are going to bag-off and others are going to ascend on the shotline, it would be nice to know beforehand. If the group want to use a lazy shot or a trapeze, again it’s important that I know in advance.
“And it’s also important for the divers to know that, if a trapeze is used, they don’t bag off and drift on their own unless they really have to (ahem, Nigel!)”
I sought the Dacorum guys’ opinions on SMB use, and they told me about their standard operating procedure.
They use red markers for all their dives, taking at least two, regardless of depth.
In addition, each diver has a yellow buoy, to be deployed on deco stops only if additional gas is required.
If the skipper sees a yellow marker, the idea is that he lowers a drop-tank of nitrox 32 to the diver below.
Rebreather diver Dave Allen has the words “Send Gas” written on his yellow marker, to avoid any confusion.
Ian Taylor approves of the system.
“As long as the divers let me know that they operate this way, and remember to supply the tank full of the correct gas, complete with regulators, line and floats, I have absolutely no problem,” he told me. “However, they do need to realise that it’s not an easy task for a boat-
driver and crew, especially in choppy conditions, so they should request gas only if they’re in real trouble.
“The system is used quite extensively by the various technical diving groups who dive from my boat, although it’s not standard practice throughout the whole fraternity.”
Having been left adrift at sea, I will never leave it to chance again, because it’s terrifying.
I hope none of you ever has this experience. The chances of it happening are slim, but if we dive without any surface marker aids, we not only take too much of a risk but ask an awful lot from our skippers, which is at best selfish.
Take a step back, and try to see your dive from the skipper’s point of view.
|Surface Location Aids |
The Pros and Cons
AUDIBLE WARNING DEVICES
Whistles and air horns are used extensively around the world by divers, and some BC manufacturers supply and fit a whistle to their products.
In theory these can be used at the surface to attract attention, but in practice ambient noise levels can be high on a dive-boat, with the skipper in the wheelhouse and waves slapping the hull, combined with diesel engine and wind noise. You may have little or no hope of being heard.
Marine flares are an excellent solution – in theory. They can be highly visible over great distances and are easy to deploy. In practice, however, they may fail to ignite, especially if you have had them for a while.
Imagine being in trouble, and getting a mere fizz and splutter as your last-resort call for help.
If they work, they are visible only for a short time, and a number may need to be deployed before they are spotted.
It is also important to have a flare or two available when the SAR teams get close, for final location.
For travelling divers, they are impractical, I wouldn’t fancy trying to get any through airport security.
LIGHTS, STROBES & REFLECTORS
Most divers carry submersible dive lights. With lighting technology now streets ahead of the old filament bulbs and ni-cad batteries, super-bright lamps with huge burntimes are readily available at reasonable cost, and these can be aimed at your dive-boat from quite a distance to alert the crew to your position.
High-intensity strobe lights can be used as a passive location aid, too, and in low light or at night, submersible lights and strobes are the best location devices available.
During daylight hours, however, they are less effective. The light emitted from a torch at sea level becomes a “blinking” light due to wave action. This has the effect of mimicking sunlight reflected from the water surface, possibly rendering your dive light invisible.
Reflective strips or patches on your dive kit, hand-held mirrors or even the back of CDs suffer the same fate.
These could prove impractical during the day, and totally ineffective at night.
HIGH-VIS SUITS & BCS
Emergency-service personnel, road workers and school-crossing attendants all wear fluorescent hi- visibility conspicuity jackets and clothing, making them easy to spot in urban environments.
Hi- visibility dive suits and BCs have the same effect, so in theory make an excellent choice.
In practice, however, they will be mostly submerged during the surface phase of a dive, substantially reducing their effectiveness.
If we’re adrift we’ll use just about anything available to make ourselves more visible.
An effective way to do this is to remove one of your fins and hold it aloft to increase the profile seen at the surface – both fins increase your profile still further.
Brightly coloured fins work best in this respect, although most divers I know wear black.
Expect to tire quickly, however. It takes a lot of effort to hold a fin, more so two, above your head for any length of time.
Flags are for use solely at the surface. They can be stored rolled up and tucked under some bungee around your tank. Most flags used as surface markers are attached to a collapsible three-piece spring-loaded pole, which makes deployment a simple task.
The extended pole is around 2m long and the flag area some 55sq cm. Flags can be supplied in yellow or orange or a combination of the two colours. A wrist lanyard prevents them being dropped and lost.
The elevated height and reasonably large coloured surface area makes this marker one of the most visible. The 1999 Heriot-Watt sea trials found that this type of flag was seen easily from up to a mile away, and remained discernible from nearly twice that distance.
A small strobe light can be attached to the pole tip, maximising the possibility of the diver being found in low light or darkness.
There are no obvious disadvantages in carrying and using flags, other than they can’t be deployed until you reach the surface.
For travelling divers they’re light and unobtrusive, but can pack a real punch if you’re in trouble.
Delayed surface marker buoys can be used to mark a diver’s position while submerged. Attached to a reel, the deployment can be made at any point in the dive, most often during the ascent, in the safety-stop phase.
DSMBs are usually tubular in shape and around 1.5m long. They may be fully open at the base or self-sealing, requiring a valve for deflation. Air is inserted into the base opening using a variety of methods, most commonly a spare regulator; though some buoys come with small inflation cylinders included.
Open-ended DSMBs can dump air while at the surface if they’re allowed to lie flat, so self-sealing versions are the safest option. They come in hi-visibility yellow, orange, red or a combination of colours.
In my opinion a large, good-quality, self-sealing, brightly coloured DSMB, used with a large reel holding enough line for the planned depth, should be considered as standard diver Personal Protective Equipment (PPE).
However, deploying a DSMB, especially in midwater, can be tricky and requires training and practice.
Once you’ve acquired the skills, you shouldn’t enter the water without a DSMB. As back-up, or an alternative, diver flags should be held in equal regard.
A powerful dive lamp with fully charged batteries and a smaller back-up should be considered essential kit for dusk or night diving, with a strobe as back-up.
Ian Taylor, Skin-Deeper, www.skindeepdiving.co.uk, 07971 977595
Bowstone Diving Products, www.bowstonediving.com, 01663 735361
Buddy DSMBs, www.apvalves.com, 01326 561040