I'm working on my PADI DM now, and have assisted in a number of OW classes where the visibility is really bad (<5'). Usually these classes are 4-6 students with an instructor and 1 or 2 DMs. As part of our training (there are two DMC's in this class) my instructor has asked that we come up with some thoughts on making the OW classes better for the students, and minimize the need to surface to find lost divers. Below is a compilation of thought I have on this based on my experiences. Probably not anything new to most of you, but I would love to hear your thoughts and ideas on this. (Moving to another location with better vis is not an acceptable answer!)
The real goals here are to make the class flow smoothly, and keep the students calm and together while swimming in very low visibility. Thanks.
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Low Visibility Student and Buddy Tracking Thoughts
Tracking students in an unconfined low-visibility environment can be challenging. Problems with separation beyond the visible distance can cause confusion and anxiety at best, and time delays, re-surfacing or lost divers in the worst cases. This paper attempts to compile some steps that could be taken to reduce problems associated with this issues. It is specifically meant for open water classes where the instructor may be assisted by other dive masters.
Most of the classes that I have attended, or assisted have been in a lake where the visibility ranges from 15 feet on a clear day, to less than 5 feet on a day with a lot of other classes and water movement. This visibility is usually constant from the surface to, and between, the platforms that are used for the classes. To complicate matters, there are often multiple classes on the platforms or swimming between them. One major challenge is to keep your class from getting mixed with another class during an exploratory swim.
Ill separate the thoughts into two parts. First, the dive planning, and second the dive itself.
Dive Planning:
The Dive:
Missing Diver(s):
We rely on our five senses for everything. Underwater, taste and smell dont do much good for locating others. If we could see them, then they arent missing. Touch is useful if there were a buddy line in place, but this is usually not the case for classes. This leaves sound. To help locate a missing diver, all instructors and DMs should carry noise makers of some sort, and agree on a set of signals such as:
These noises could be repeated every 10 seconds, and after the 6th repeat, if no response is received or the party located, the diver should surface.
The real goals here are to make the class flow smoothly, and keep the students calm and together while swimming in very low visibility. Thanks.
=================================================
Low Visibility Student and Buddy Tracking Thoughts
Tracking students in an unconfined low-visibility environment can be challenging. Problems with separation beyond the visible distance can cause confusion and anxiety at best, and time delays, re-surfacing or lost divers in the worst cases. This paper attempts to compile some steps that could be taken to reduce problems associated with this issues. It is specifically meant for open water classes where the instructor may be assisted by other dive masters.
Most of the classes that I have attended, or assisted have been in a lake where the visibility ranges from 15 feet on a clear day, to less than 5 feet on a day with a lot of other classes and water movement. This visibility is usually constant from the surface to, and between, the platforms that are used for the classes. To complicate matters, there are often multiple classes on the platforms or swimming between them. One major challenge is to keep your class from getting mixed with another class during an exploratory swim.
Ill separate the thoughts into two parts. First, the dive planning, and second the dive itself.
Dive Planning:
Describe to the students each step of the dive.
o Buddy pair and DM assignments are made, and stress that the assigned group must stay together.
o We will descend (Holding line, watching line, no line) and meet on the platform below. We will all wait at the platform until everyone is there.
o Describe how to find the platform if you miss it on descent (at 33 deep exactly, current probably pulled you south, so go north first).
o We will do various tasks (describe each task)
o We will then do an exploratory swim with the following dive buddy pairs and order of pairs.
o Describe start and end of swim, and method of navigation. For OW classes, we often string a large rope between platforms to allow the class to follow for this swim. Otherwise, depth and compass headings should be discussed.
o We will surface after everyone reaches the end point.
Describe lost buddy procedure.
o If you get lost, you should search for 1 minute. If still unable to find group, do a normal ascent and wait for instructor or DM at surface.
o While searching, listen for noise makers. They cant give direction, but as you move you can tell if you are getting warmer.
Review notable scuba gear on each diver.
o The instructor has yellow fins.
o Your buddy has a green bathing suit.
o Optionally, attach a colorful strap or marker to each students tank, and each instructor or DMs tank. Maybe put 2 on the Instructor and DMs to make them distinguishable.
The Dive:
Instructors and DMs must be sure to keep buddy pairs together. If one is descending faster than the other, stop them and move them back to their buddy. Often students are too focused on equalizing, and descending to remember about their buddy.
Once at the platform, keep the students at the same level (i.e. holding the bar or kneeling together). 5 visibility allows a DM to see only 3-4 students at a time if they are together.
Missing Diver(s):
We rely on our five senses for everything. Underwater, taste and smell dont do much good for locating others. If we could see them, then they arent missing. Touch is useful if there were a buddy line in place, but this is usually not the case for classes. This leaves sound. To help locate a missing diver, all instructors and DMs should carry noise makers of some sort, and agree on a set of signals such as:
One pulse (shake or blurt) I cant see you, and I am sitting still waiting on you.
Two pulses I cant see you, and I am actively searching for you. This could also be a response to hearing a single pulse.
Three pulses I cant see you, and I am doing a normal ascent now.
These noises could be repeated every 10 seconds, and after the 6th repeat, if no response is received or the party located, the diver should surface.