Safety stop at 15'..........always

[diver 85]

Learned to dive when 60' per minute and no safety stop were the rules.

Now I do a safety stop whenever a slow swim to the surface isn't more interesting. i.e. a boat dive. Shore dive I just swim to the beach/shore and don't worry too much about timing my depth.

It is however a safety stop so I will skip it altogether if I have a good reason to. i.e. if staying down is going to be unsafe for whatever reason I will skip the stop and not sweat it at all.

Last time I skipped it we were in a high current area and the current changed direction just before we exited the channel - staying down would have blown us into the middle of a high current 9 knots plus narrow channel with lots of boat traffic. Getting out of the water was a priority so skip the stop. First dive of the day, 40 minutes or so at 70 feet as I recall. We were near the end of the dive so had already come up to 40 ft or so.

It does bother me that some divers will put themselves at risk just to make sure that they do the safety stop because its a rule.

I remember diving Belize in the mid 80's with dive profiles of 90ft. for 30 minutes or untill it was hard sucking air out of the 72 tank, which ever came 1st........lol, kids now 'have it made'..............

 

[peterbj7]

I've seen several people get "unearned" bends - ie. they did everything right by the book and still ended up in the chamber. I don't want to join them, so I make deep stops AND always spend at least 3 mins at around 15'. Often longer. And, most importantly, I take a full minute to ascend those final few feet from the safety stop. It's alarming how many people check their computers, see they done the alloted time at 15', and shoot to the surface. The rate of pressure change that close to the surface is the greatest they've experienced in their entire dive.

 

[lazyturtle]

When asked about it he always said his computer (a very old relic I wouldn't trust)
didn't tell him he was in "deco" so why would he do a deco stop.

Just because his computer was old doesn't make it untrustworthy. That being said there's a difference between a deco stop and a safety stop. He obviously didn't understand the difference. Which says something about him.

many dives were 100' deep or more.

Modern tables have mandatory safety stops at this depth.

Anyhow, this isn't the first time I have watched a diver skip safety stops after deep dives. How many of you do Safety Stops regardless of what your computer says?

Honestly I do a safety stop on all dives deeper than 50'. I don't do extra stops, though I've read the literature that suggests that this is safer.

To me the issue is more why this guy wouldn't do what the rest of the group was doing. Personally when I lead a dive I tell divers that the MUST do at least what I'm doing (safety-wise). If they want to do more (as you mentioned extra stops on the way up) I'm fine with it, so long as they explain their plan before the dive. If they cannot comply with these simple rules, they cannot do any further dives with me.

 

[bleeb]

The Bay of Fundy maybe?

As much as I hate to do it, I will quote a sentence from Wikipedia about the Bay of Fundy:
"The name 'Fundy' is thought to date back to the 16th century when the Portuguese referred to the bay as 'Rio Fundo' or 'deep river."

The Clean Current website on the Bay of Fundy lists the tidal speed of 4.5 meters per second. I did the calculation (because I'm a geek) and it is approximately 8.75 knots. That is a rip-roaring current!

Of course, I don't know why anyone would want to dive in the Bay of Fundy since the current is so strong and fast it causes the water to be very turbid.

[hijack]Actually, I've heard the diving in some parts of the Bay of Fundy is spectacular, especially in the Passamaquoddy Bay area. Keep trying to make a trip there to try it myself, though. (For those not familiar with the area, these are the biggest tides in the world: 8-10 m. I'm guessing 2Tours is, since he brought it up. )

The cold water upwelling makes for some of the densest concentrations of marine life off North America after some parts of the Caribbean and Vancouver Island. Whales summer and calve there because of all the food.

Vis is apparently not bad, I guess since the cold deep water is free of algae, and replaced daily. And I would imagine that in some spots, any sediment has been swept away by the afore mentioned rip-roaring currents.

The catch is that there are only two 45 minute windows a day when you can dive at low and high tide, and that even these may not be safe at some times of month. There are also opinions that high tide is better for having less sediment, but low tide is better because it gets you closer to the marine life.[/hijack]

 

[MXGratefulDiver]

For you unbelievers out there:

Dodd Narrows - just checked current for today max flood is 8.1 max ebb -7.1 knots. Typical is 5 - 6 spectacular dive spot - at slack tide - and not for beginners.

April 7 9.2 flood -8.1 ebb.

May 7 9.7 flood -8.3 ebb.

We were not at 9 knots as we were diving the slack, but sticking around to do a safety stop as the current increases to up to 9 knots is not a good plan. The plan was to drift with the slack current and get around the corner before the tide changed - we missed by about 10 feet - swimming as hard as I could I was being blown back along the rock face faster than I could swim in no current - and the tide had just turned. Time to surface and get back on the boat.

Here is a description from one of the local tourist brochures (not sure I would put it at #2, but it is up there):

Situated 5 nautical miles SE of Nanaimo, Dodd Narrows is rated the #2 dive site in BC. Only 55 metres wide at the narrowest point with a max depth of 33 metres. The 8-9 knot currents in this picturesque channel create an ideal habitat for a lush assortment of colourful marine invertebrates. Due to the strong currents, Dodd Narrows can only be dived from a boat at slack water. The Mudge Island side of the Narrows with it's heavily colonized sheer vertical faces and overhangs is the diver's preferred bank. Living in Dodd Narrows are many species of Sea Anemone, Aggregating Anemone, Sea Stars, Mosshead Warbonnets, Puget Sound King Crab, Orange Cup Corals, Red Irish Lords, Rockfish and Cod. Occasionally during the winter months California and Stellar Sea Lions can be observed feeding on Salmon in the swift tidal stream. A photographers dream!

I love that dive ... my favorite in Nanaimo ... TONS of color ...

HOWEVER ... two points ... first, most sane people don't dive it on days when the current's ripping like you quoted above. And second, there are places along the way where you can duck into protected coves and get out of the current. The measurement is made mid-channel, not along the wall where people dive. On the dive where the photo above was taken we were caught in one of those little sheltered areas ... the current was very strong away from the wall, but not very strong alongside it. We did our safety stop and surfaced in relative calm ... and less than 100 feet away it was like a roaring river with standing waves three feet or more in height. The boat drifted by and tossed us a line ... pulling us out of the little sheltered area. Once we got into the current we were drifting with the boat. Except for the fact that we were moving along at a brisk pace with respect to shore, it wasn't a big deal getting aboard, since both we and the boat were moving at the same speed.

... Bob (Grateful Diver)

 

[Blackwood]

The channel cuts on [SIZE=-1]Eniwetok Atoll must have fun at close to that.
[/SIZE]

Same with the inlet at Rangiroa when the tide changes.

 

[Blackwood]

The rate of pressure change that close to the surface is the greatest they've experienced in their entire dive.

The rate change of pressure has nothing to do with proximity to the surface. It has only to do with how quickly you move through the water column.

P.S. I SO envy your location

That being said there's a difference between a deco stop and a safety stop.

One you are stopping your ascent to decompress. The other you are... stopping your ascent... to decompress.

The only difference is the name. One sounds "scary" and makes it hard to market "non-decompression diving." The other doesn't.

 

[Darnold9999]

Bob:

"3 foot or higher standing wave" sounds like about a 4 - 5 knot current, more than I would be comfortable diving in!

Totally agree - this is also one of my favorite dives. I also agree with your two points. There is no way I would dive this site in full flood and yes if you are prepared you can get into an eddy along the wall. Don't know what the current was that particular day, however it was far more than we could fight just 2 minutes into the change. We were not prepared for even this as the plan was to get out of the current altogether. The change surprised us. The shift was early. We got caught at a point just at the entrance to the channel and had almost no control over where we could surface. I personally did manage to surface near the shore in a bit of an eddy but that was luck not planning - my buddy didn't and ended up 20 yards away out in the channel and was drifting away pretty quickly. I had to swim to him so the boat could tow us out of the way - others ended up spread out down the channel. One buddy pair ended up completely on the other side of the channel.

The tug with the raft of logs trying to get through the channel at the end of slack was pissed as the dive boat towed divers out of his way. I gather that the air was pretty blue as the change was a bit early and he was running out of time before he was blown back down the channel.

The point being current like this is unpredictable, current predictions in this area are accurate, but not precise - and sometimes it is safer to surface than to attempt a safety stop. I wasn't about to stay down another three minutes - ride the current and hope I found an eddy that worked. The spot I was in worked for me, but who knows for how long and I was not about to get blown into the channel with boat traffic heading my way.

 

[2Tours N Iraq`]

Darnold9999, I would have done the exact same thing you did. I would also like to point out that this is one of those times when the safety stop would have been more hazardous than helpful and the right decision was made. Always use the noodle between your ears.

 

[Cacia]

If they cannot comply with these simple rules, they cannot do any further dives with me.

I totally understand where you are coming from, as leading divers can be like herding cats and a big responsibilty. Do you see the confusion though, when PADI tells certed divers they are responsible for their own profiles and then they go on a dive vacation and another person insists on taking responsibilty? I think it makes for a grey zone that is fraught with confusion.

I don't know the solution, but I am always careful about giving too many requirements, as a DM, because I think this implies a certain level of responsibilty I can't really assume with a large group of certified divers.

I couch my briefing as a "suggested profile" and nothing more.