Intro to Cave - Day 1

Dive 1: Average depth - 2.4 m ; Max depth - 4.7 m ; Dive time - 20 min

Dive 2: Average depth - 5.4 m ; Max depth - 6.9 m ; Dive time - 35 min

Dive 3: Average depth - 4.8 m ; Max depth - 6.7 m ; Dive time - 41 min

Slowly, the rays of sun from a hot Mexican day fade away as we venture into the cave. I take a deep breath from my regulator, this is it. From this point forward, I must contend with the fact that any series of mistakes can kill me. From this point forward my life is in my own hands, and every breath must be calculated. But it is not fear or stress that takes my mind, it is peace. I can hear the air rushing from my tank, through the first stage and into the second, and then finally into my lungs. It is dry, strong, and every breath is meaningful. As Tom Mount puts it, "Breathe and connect." That is all there is now. With every breath you learn more about the cave, about formations that have taken thousands of years to take form, but also about yourself. This is not to say there was no stress, oh, there definetely was. But stress is good, if it is controlled and managed. This was my first time sidemounting in over two years - unfortunately carrying all the equipment required can be a burden for trips that are not dedicated to diving. With the equipment adjusted, we began doing some drills and swimming in open water. This was mostly so my instructor, Luis Leal, could gauge my skill level. We practived frog kicks, helicopters, reverse, shuffle kicks, swimming sideways and switching regulators. Once this was done, we decided we were all comfortable enough to head into a cave. We followed Luis' very trenchant pre-dive drill, which I will outline below.

• Bubble Check - First step in the pre-dive drill is to conduct a bubble check. This is easy for sidemount divers, as we can only slighly pull our tanks out and look at the first stage ourselves. This is imposisble for backmount divers, hence they must ask a buddy to conduct their bubble check.

• Equipment Matching - This step is crucial not only to be aware of what equipment you team has, in case you need it, but also to check all your own equipment to make sure it is working. Don't wait to be inside the cave to discover your primary light is not working! Luis starts with his air supply. First, we go over what tanks we are carrying and what setup we have mounted to each tank. For example, I would say, on my left side I have a 12 L tank with a first and second stage. The first stage has a short hose to my second stage, which is working (take three breaths from it to confirm), I also have a BCD inflator hose which is working. Next, I would repeat the same procedure for my right hand tank. Second, we discuss lights. This goes something like: I have a primary light on the left side of my helmet, and it is working, I also have a backup primary light attached to a butt d-ring, and two backup lights. My buddies must respond with, me too, in case they have the same equipment and it is all working, or they must specify what they have if it is different than mine. Third step is the accessories; here we go over line-cutters, reels, notepads or slates, computers, etc.

• Dive Plan - The dive plan is a critical part of the pre-dive drill, and Luis taught me the SADDR (Sad Doctor) acronym. Sequence: who will be the team leader? Who will be the second diver? And who will be the third diver if applicable? Air: How much air do we each have? Calculate total air for all members and choose the member with the least amount to define thirds. Distance: Are we setting any distance limits to the dive? This can be useful when diving with DPV, or useful in general to avoid mission dives when they are not wanted. Duration: How long are we diving for? I am still a no-deco diver, so I must stay within NDL. This must be discussed here. Review: Here we do a quick review of all that has been discussed and, most importantly, we discuss the navigation plan for the dive. Ex: Team leader will setup a primary reel from OW to the cave line, we will then jump the first arrow to the left onto line A, then when we find a big room we will look for another line by a boulder on the right side.

With the dive plan done, we should have (if agreed upon) three instances where the dive will be called, air, time, or distance. Here we must remmeber the golden rule as well - the abort dive signal is like royal decree, it cannot be argued with and it cannot be questioned! Anyone can abort a dive at any time for any reason, and all must comply. Luis also states that a diver should not ask the other for remaining air in a cave. Each diver must be aware of his own air supply, and call the dive as needed.