Jon lines

[Walter]

A jon line is attached (usually with a clip) to the anchor/mooring line. The diver then retreats to the end of the line. It is very useful in a combination of current and seas. Floating free works well to keep you at the same depth in seas, but when current is also present, the jon line keeps you from drifting away. On crowded ascents they are handy to get you out of the crowd, so in that situation I use one even in the absence of seas. I normally use a buddy line as a jon line because I am able to adapt it for so many situations/uses.

 

[O-ring]

...in the sense that they can be used at gas switches since you are about to spike your ppo2 from whatever you were diving for the working portion of your dive up to 1.6. If you were to tox at a gas switch, it seems more likely that you will be rescueable if you are attached to the line where your buddy can get to you instead of flying in the current and possibly sinking.

The scenario here was one where we were NOT live boating, so drift deco was an undesireable last resort. This was an ascending the anchor line scenario. Obviously, a jon line has no place doing a drift deco...what would you attach it to?

We never got anywhere on this though I don't think...good discussion topic though..

 

[Braunbehrens]

In my opinion jon lines are a compromise that carries too much risk. Diving is all about accepting a certian level or risk. There are simply too many thing that can go wrong with a jon line. Drifting the deco is a much safer alternative.

Before I get jumped by people who are going to tell me that there are places where you can't drift....well, there are places where you can't dive. If you want to make this compromise in safety because you feel the goal is worthwhile, then that is your choice.

However, saying that it is safer to use a Jon line when doing a gas switch is in my opinion a mistake.

If you do the gas switch properly, and this means that you are in close proximity to your buddy and you are observing each other, the Jon line will only add more problems.

This scenario also assumes that you not only use a Jon line, but that you are clipped into the jon line. Clipping to the jon line is adding even more danger to an already dangerous situation.

I hope I'm not being rude in any way here, and I'd be glad to discuss any of this if we can keep it polite.

 

[JeffG]

Braunbehrens once bubbled...
In my opinion jon lines are a compromise that carries too much risk. Diving is all about accepting a certian level or risk. There are simply too many thing that can go wrong with a jon line. Drifting the deco is a much safer alternative.

Before I get jumped by people who are going to tell me that there are places where you can't drift....well, there are places where you can't dive. If you want to make this compromise in safety because you feel the goal is worthwhile, then that is your choice.

However, saying that it is safer to use a Jon line when doing a gas switch is in my opinion a mistake.

If you do the gas switch properly, and this means that you are in close proximity to your buddy and you are observing each other, the Jon line will only add more problems.

This scenario also assumes that you not only use a Jon line, but that you are clipped into the jon line. Clipping to the jon line is adding even more danger to an already dangerous situation.

I hope I'm not being rude in any way here, and I'd be glad to discuss any of this if we can keep it polite.

What is the compromise that you are speaking of?
What are the "more problems" that the Jon line creates?
What the additional danger that is being added to the situatation?


Where's the Beef?

 

[JeffG]

Diver0001 once bubbled...


It must be dialect. What's a " Jon line"? Is that what I might call a "buddy line", a short rope that both divers hold onto during the dive?

R..

Walters Post

A jon line is attached (usually with a clip) to the anchor/mooring line. The diver then retreats to the end of the line. It is very useful in a combination of current and seas. Floating free works well to keep you at the same depth in seas, but when current is also present, the jon line keeps you from drifting away. On crowded ascents they are handy to get you out of the crowd, so in that situation I use one even in the absence of seas. I normally use a buddy line as a jon line because I am able to adapt it for so many situations/uses.

 

[O-ring]

Before I get jumped by people who are going to tell me that there are places where you can't drift....well, there are places where you can't dive. If you want to make this compromise in safety because you feel the goal is worthwhile, then that is your choice.

There are places you can't drift and in those places, should I decide the goal is worthwhile and I choose to dive, I may choose to use a jonline.

 

[Doppler]

Would it be possible to actually get some facts here...

Braunbehrens once bubbled...
In my opinion jon lines are a compromise that carries too much risk. Diving is all about accepting a certian level or risk. There are simply too many thing that can go wrong with a jon line. Drifting the deco is a much safer alternative.

It's not clear what safety rules a Jon Line compromises, and why drifting is "a much safer alternative." Both have suitable applications.

Now, if I read this correctly:

Braunbehrens once bubbled...
Before I get jumped by people who are going to tell me that there are places where you can't drift....well, there are places where you can't dive. If you want to make this compromise in safety because you feel the goal is worthwhile, then that is your choice.

You are saying that if there is a current, and drifting or live boating is not possible, you see the risk as too great and therefore will not dive. Is that correct?

If that's your opinion, I support your right to hold it... after all: Anyone can call any dive..... etc. etc. Just as long as you're not going to be judgemental about those who hold a different opinion.

It just seems that these discussions quickly degenerate into a pissing contest where one side is black and the other is white... when mostly, there is a huge gray area....

Now, there are some side issues here about gas switches and that's how these discussions get hijacked. Let's try to stay focused on the central issue...

Using a Jon Line is an acquired skill... just like anything else. Jon Lines are not advised on every dive, and should only be carried when needed (Hogathian rules) but I fail to see how a simple piece of climbing webbing with a couple of loops in it, is -- in and of itself -- dangerous.


Doppler

 

[DiveTub]

I love my jon line and use it on every Deco Dive, why would anyone want to hang onto a bouncing mooring or anchor line with 10 other people when you can tie off, hang back and have a comfy deco.

Mine is 3m long and made from Shock cord, it is great as if there is any bounce it stretches and takes out the pulling nicley.

 

[Walter]

"only be carried when needed (Hogathian rules)"

I disagree. I carry my multipurpose buddy line on every dive. In the event I need to rescue a panicked or exhausted diver on the surface, I use it to tow the diver. A quick loop around around the tank valve and I'm in position to make a safe and relatively easy tow.

It's part of my standard safety equipment.

 

[techdiverKP]

It's been said already, but having a jon line to get away from the crowd at that 10-15-20ft stop is a stress reliever in a major way. It also keeps you from getting lazy, letting the down-line/anchor line affect your stop depth. Pinpoint buoyancy and a good jon line can make for a relaxed and safe deco in some conditions.

It CAN even be used on drift decos if you're doing a group drift on a down-line. In high-current, open ocean dives, it's a lot safer and more relaxed doing your deco that way, with a live boat on the surface tracking the surface float that your down-line is attached to. Much easier to splash support divers on also if your entire group is decoing on one free floating down line.