Cookie vs REM vs TEM

[steinbil]

Quoted from Danny Riordan's FB:

What is a Cookie?

In the previous posts I wrote about the development of the cookie with its background. A cookie is a small, round, piece of plastic that contains a unique identifier or message. It's designed to be left at specific points in a guideline in a cave system, allowing divers to confirm their location and navigate safely.

"REM" and "TEM"

A few years after several of us were using the cookies I developed, my friend and dive buddy for a long time, Bil Phillips came to me one day at a dive site and mentioned he had developed a "smart cookie". I must admit I laughed at first because I imagined he thought the cookie must have had a low IQ . He went on to explain he had developed a rectangular marker with one side being wider than the other (in reference of where the attachment to the cave line takes place). He then showed me he had carved small dimples, similar to the ones found on domino pieces. The purpose was so a diver could feel it, even in zero visibility. On the wider side, a diver could write any valuable information once it was secured to the line, like compass heading of a potential lead during exploration or any other information you would think necessary. His “intelligent markers” were stored in a piece of surgical tubing where a pencil was found at the end and that's the pencil used to write on these markers. I admit the concept was good and innovative, as it was.

Sometime later, these markers started to get used in a way that I don't think Bil even thought about initially. Divers started assigning "direction" to one end of the marker vs the other and eventually the name of Reference Exit Marker or REM started. The idea is that one portion of the marker (typically the wider one) points to the exit. The potential problem I see with this way of using these markers is that if a person that is not cave diving all the time can forget which side points to the exit or if stress starts to build up and on top of this you add factors like limited visibility, the chance to make a mistake, or forget which side points out is there. No doubt about it.

Some divers reduce this risk by adding a tactile marking so the exit is more evident. When divers taking classes with me ask if they can use REMs for training, my answer is to ask them 2 questions: 1) do the markers have their name and 2) are they a different shape than a line arrow. Since the answer is yes to both, they can use them, as long as they don't assign value to one side vs the other.

The way I see it is arrows and non-directional markers (cookies or any other form) are the equivalent of black and white and the REM is a gray area that could create confusion, not for other divers, but for the person that intended to have some form of reinforcement.

A few years ago I was told about a variation of the use of the REM. This concept is the Team Exit Marker or TEM. I was told that this concept works the same way as the use of a REM, with the variable that only one marker is used per team, instead of 1 marker per diver.

Conclusion

I must admit that the invention and development of the cookie has had a profound impact on the world of cave diving and I never thought it would become an international piece of equipment that so many cave divers carry with them. This simple yet effective tool has improved safety and efficiency, making it an essential part of every cave diver's kit. As cave diving continues to evolve, the cookie remains a testament to the innovative spirit of cave divers

Commence discussion...

 

[PfcAJ]

REMs don’t solve anything but can cause confusion.

Pass.

 

[DiveLikeAMuppet]

As a stupid GUE diver who only dives touristy places, I prefer cookies - or clothing pegs, don’t judge, lines in the UK are thick.

The problem with a REM is that you can place it at the wrong side of a T pointing in the right direction, or the other way around - so it’s ambiguous. Cookies are unambiguous - so the post sounds very sensible to me.

But I do know people who are really passionate about their super-customised REMs which fits the bigger training picture. I’ve been taught to tie off a jump wherever (system arrow, directly on the line, without confusing other teams). Other people I know have been taught to always tie off into their REM and not drop any other personal markers (team members would drop one next to the REM) - so in this respect it REMs are part of a bigger training style.

 

[Norwegian Cave Diver]

REM’s allow a diver to carry one type of marker and replace those redundant arrows and cookies.

Pass.

 

[Invader]

I use all REMs, and one 'out of cave' cookie if I have to leave. Will pass on TEM.

 

[LFMarm]

I only use REMs except for one arrow in my pocket in case of lost diver. The space to write a message and the ability to simplify what I carry are the 2 main reasons for me.

 

[inquis]

The problem with a REM is that you can place it at the wrong side of a T pointing in the right direction

But why would anyone ever place it on the wrong side at all?

 

[DiveLikeAMuppet]

But why would anyone ever place it on the wrong side at all?

I’m a muppet, not a super human infallible cave diver who never makes mistakes. So of course I placed a cookie on the wrong side of a T once. My teammate noticed and I noticed about a second later. It’s obvious.

Being a muppet, I can imagine myself placing a REM on the correct side of a T but pointing in the wrong direction. That is confusing and more difficult to spot. Would you trust the position relative to a T or the direction? What if you are stressed?

 

[rjack321]

If you stick to original exploration this problem solves itself

 

[inquis]

Being a muppet, I can imagine myself placing a REM on the correct side of a T but pointing in the wrong direction. That is confusing and more difficult to spot.

I'd say that a cookie on the wrong side is even more difficult to spot. At least with counter-indications with a REM, you have an indication that something is amiss and can take a moment to consciously think, verify with the team, look at the cave, etc. It takes two mistakes to achieve the completely erroneous condition (wrong side and wrong direction) compared to one with a cookie.

Would you trust the position relative to a T or the direction?

Neither when they conflict. I'd look for additional evidence.