Typical tdi deco procedures advanced nitrox course length.

[rjack321]

I’m really interested in learning how the locals do deco on Great Lakes wrecks with fixed mooring lines when the line is really jerking due to wave action at the surface. Jon line or do they shoot a lift bag to deco next to the line? Dang near had my arm pulled out of my shoulder doing a safety stop on the line with 3-4ft waves topside last weekend.

I'm not Great Lakes "local" but I've done some diving there. I get off the line and hang next to it midwater. There's barely any current so staying in sight of the line is not difficult, in fact if there is a little bit of wind driven current deco gets easier since kicking slightly mitigates the tendency to drift up or down a tinsy bit. Since doing deco on CCR you cant fine tune to the same extent you can on OC with breath control. I've done up 40+mins at 20ft that way just hanging around nearby midwater.

I don't know any Great Lakes vessels putting divers in the water with 4ft waves. Molly V, Black Dog, and Discovery wouldn't go out in that kind of weather although I suppose a thunderstorm might come up.

 

[EireDiver606]

I’m really interested in learning how the locals do deco on Great Lakes wrecks with fixed mooring lines when the line is really jerking due to wave action at the surface. Jon line or do they shoot a lift bag to deco next to the line? Dang near had my arm pulled out of my shoulder doing a safety stop on the line with 3-4ft waves topside last weekend.

Not just the Great Lakes but anywhere that can get rough.

 

[Marie13]

Not just the Great Lakes but anywhere that can get rough.

Local practices may differ.

 

[rhwestfall]

I either let the line slide in my hand, or use a JonLine if I need to be on the line....

 

[EireDiver606]

Local practices may differ.

No I mean it would be interesting to know what divers do in rough sea conditions NOT just in the Great Lakes but everywhere else also.There are places much rougher than GL.

 

[kensuf]

Jon line for rough seas with no current, drift deco for current (but you better have a proper support crew!). Both will allow you to maintain static buoyancy in the water column, it's only when you're tethered to the bottom (like an anchor line) that you get hosed by waves. This should be covered by your instructor during AN/DP.

 

[rjack321]

No I mean it would be interesting to know what divers do in rough sea conditions NOT just in the Great Lakes but everywhere else also.There are places much rougher than GL.

It depends

Up here we either come up the anchor line (to the surface) with or without a scooter, come up the anchor line partway and shoot a bag and drift, shoot a bag from the bottom and drift. By and large we don't use Jon lines since 2 or 3 knots on a Jon line is really uncomfortable and buddy communication is terrible. If there's no current then we just stare at the upline.

 

[KentB]

Mine was 8 dives and roughly 600 min bottom time took 2.5 months
We just did 1dive/day