We are going to triple up on the "Diving in Antarctica" series this week. In this entry, I’ll take you from the dive locker to the dive site from the diver’s perspective and get us geared up and ready to drop into the water. Later this week, Maggie will do the same trip from the perspective of a dive tender. Then, Kevin will tell you what it is like diving into the frigid Southern Ocean.
In my last entry I talked about getting our gear ready in the dive locker. While the divers are doing the final part of their gear preparation and suiting up in the dive locker, the tenders are getting the boat ready and loading our heavy gear into it.
As Maggie will describe, there is a lot of work involved with getting the boat ready and loading two to three hundred pounds of dive gear into it. The divers help a little but usually not very much. That isn’t because they are lazy, but rather because it is very important that they not get sweaty.
All that warm underwear I talked about in my last entry that we have on under our drysuits is wonderful after we get in the water and usually just fine when sitting in the boat on the way out. But it is a lot more than we need to stay warm otherwise. Particularly on a relatively warm (note I said relatively!) or calm day, if we do much more than walk to the boat we can work up a sweat. That isn’t good.
Even though we have on a lot of "hi tech" fabric that wicks sweat away from the body, if we get wet enough the underwear still isn’t quite as efficient in keeping us warm as it is when it is dry. Believe me, when we are underwater, every bit of the insulating capacity of that underwear is welcome! The tenders understand that, particularly those who are divers too (everyone who dives also tends at other times).
Often the tenders will have the boat completely loaded and ready to go when the divers get out to the dock. If the boat isn’t completely loaded when the divers get there, they typically help with the last of the gear.
Once the divers and gear are loaded into the boat, one of the tenders takes the helm and we head out to the dive site. Once there we choose the exact spot (relative to the shore) where the divers should drop in. Often we will cruise up and down the shore of the island we are diving off of to check that there aren’t any leopard seals around. Then we idle the motor and drift while the divers get ready.
Every diver has her or his own sequence of getting ready at this point. I’ll describe mine:
First I pull my gear out of my bag. I put my fins somewhere out of the way as I won’t need them for a while. Then out comes my mask (which has traveled in a plastic case) and snorkel. I have a small plastic bag that holds "sea drops" and my wrist tubes. The sea drops are to help keep my mask from fogging up underwater. At home, like most people I just use a bit of saliva. But I’ve found that in really cold water, this commercial anti-fog product seems to work a bit better. So I put a couple drops in my mask and rub it around (I’ll rinse it out later, just before putting the mask on).
Since I have that bag open, next I put in the wrist tubes. Wrist tubes are something unique to diving with dry gloves. They are about 4 inch long pieces of firm (but not hard) rubber tubing that we tuck under our wrist seals. As I mentioned in my last entry, our drysuits seal at the wrists so that water can’t come in. In places where the water is a little warmer, divers will often use wetsuit gloves with a drysuit and so this arrangement is perfect. Wetsuit gloves are easier to work in than dry gloves but not as warm. So we use dry gloves. There is a hard ring attached to the wrists of our suits that these gloves seal over.
What the wrist tubes do is to allow a little air to flow between our gloves and the rest of the suit. As Kevin will tell you, as we descend we have to add air to our suit as the air already in it compresses under the increasing pressure. If we didn’t have the wrist tubes to let air into our gloves, they would quickly get compressed so thin that there would be little insulation left. Plus, they would be uncomfortably tight. There are a couple other big advantages to the wrist tubes too but I’ll let Kevin tell you about those.
Next, I have a tender help me put on my weight belt. I have 38 lbs. there in addition to 5 lbs. that are already around my ankles. After that, I put an insulating foam bonnet on my head and cover that with a thin vinyl hood that is attached to my drysuit. Our heads do not stay dry but only a little water gets in. This gets trapped by the bonnet and is warmed by our body heat. I have a wet suit hood that I put over the vinyl hood for extra warmth. Not everyone uses those but I like the extra warmth.
When I was setting up my tank in the dive locker, I put the regulator mouth pieces (the second stage of the regulator) into a pocket in my buoyancy compensator vest. Ditto with the dive computer and inflator hose for my drysuit. At this point in the boat, those come out of the pockets and I turn on my air and dive computer.
Time to put on the tank. I help one of the tenders put it up on the gunnel (in a zodiac inflatable boat, the side tube). I have the left side buoyancy compensator vest strap unbuckled. I slip my right arm through the right side strap and the tender helps me hook up the left. The air dump valve on my suit (more about that from Kevin) is on the left side so it is easier to have that be the unclipped strap to begin with. After the tender helps me with that, I connect the "cummerbund" waste strap and hook up the hose that lets me add air to my drysuit.
On goes the mask. I have to work the vinyl drysuit hood over it but that is a skill well practiced. It requires bare fingers but most days that isn’t bad for the short time it takes. Next come the fins. Finally, time for the dry gloves. I’ll let Maggie tell you about putting on the dry gloves. It is more interesting from the tender’s perspective.
Once the gloves are on and both divers are set, we motor up to the preselected drop in spot. The boat driver moves in slowly, puts the engine into reverse briefly to stop the boat’s forward motion, and then puts it into neutral so that the prop isn’t spinning. He or she calls out "neutral!" to let the divers know, and then we drop in. Kevin will pick up the sensations from there...