Reasonable to limit bottom time to 45 min?

[DevonDiver]

...we usually have a simple plan, such as dive down to around 30m until one of us reaches 100 bar. Then slowly make our way up to the top of the reef, swim around at around 15m until we hit 50 bar, and then up a 5m safety stop. The boat captain usually gives us an hour.

I know this sort of planning is quite common practice, but it isn't really "dive planning". More like "computer flying" - because you're reactive to your dive computer determined NDL as the dive progresses.

Possibly, as this was my first such trip, my expectations may have been a little high.

It's one of the problems with diving in unknown/mixed-ability groups. If a group cannot be split into experience levels and/or divers aren't proactive to communicate/negotiate their own parameters, then the divemaster can only provide a standardized "one-size-fits-all" profile/schedule.

In some regions/sites, dives have to be supervised, in-water, by a divemaster, due to local legislation etc. That reduces flexibility for experienced divers even further - as it means they have to stay with the group/DM from start-to-finish on the dive.

Only the divemaster and I had computers or any type of timing device. The others did not even have watches. So basically, we had to make sure they were above us at all times.

By rights, they shouldn't even have been diving. However, necessary scuba equipment is 'agency recommendation', not a rule-of-law (in most regions). I've seen similar practices throughout Asia - lots and lots of divers hitting the water with nothing more than a depth gauge - relying absolutely on the divemaster for all dive profile control. Infrequent 'Holiday Divers' rarely have their own computer or dive watch. Dive centers don't insist on rentals (I don't know why?).

Thus, it's become commonplace for the DM to take total responsibility for those matters/functions. Not an ideal state-of-affairs... and one in which the divemaster soon becomes very cynical over the 'skill' and 'experience' of the customers they guide. The end result is the creation of the 'underwater nanny'... a divemaster who does everything for their customer divers... and, as a result, treats them with kid gloves and hyper-conservative profiles.

But surely if you are diving at a totally unfamiliar sight, you can not really plan your own dives?

Why not? What information would you be missing, that'd prevent you from calculating an NDL and approx gas consumption in advance?

Most of the input has to come from the divemaster who is experienced at the dive sites.

As mentioned before, they should (as a DM responsibility) provide an outline dive briefing. Something along the lines of a dive site map, with depths, hazards, point-of-interest and, possibly, recommendations (route, place for ascent etc).

If acting in the (separate) role of a dive guide, then they will lead a 'tour' underwater, so that customers can benefit from their local knowledge and ability to locate and identify items of interest to the customers.

What you 'see' underwater isn't the product of your core dive plan.. you should have your profile, depth, bottom time etc pre-agreed (with your buddy and the divemaster) before the dive.

I don't plan on filing a complaint. I think in future I will ask all the questions I think relevant, upfront prior to booking the trip.

THAT is definitely the answer!

Small, high-quality dive operations offer suffer from a lack of recognition for the services they provide. Quite often, divers book a dive operation based upon price or convenience - failing to investigate exactly what they'll get for their money.

IMHO, a good dive operation will provide sufficient staff to ensure small groups of approx equal diving capability/experience/qualification. They won't provide foreshortened dive profiles either. That might cost a bit more money though...

 

[bigduke12]

Well, IMHO it seems there were a few problems here. The divemaster should have provided the dive profile (including the max time), along with ensuring everyone had the necessary equipment to complete the dive. However, when this didn't happen you, and the other divers should have been questioning this.

My guess is that the divemaster was planning a square profile (18m/45mins), and then making the dive more conservative by spending more time in the shallows, however this should have been communicated to the divers. If the 45 minute maximum caught you by surprise, then what did you think was the limit of the dive? Was there any mention in the briefing of minimum gas?

The bottom line is that you need to speak up when you aren't sure of these things, and if you can't speak up for fear of getting into an argument due to your anger, then you need to work on your anger issues so that you can have a calm discussion about things that don't make sense to you.

Well, my main issue is to insure I have all the correct equipment. To be honest, I only noticed the others did not have the correct equipment when on the boat.

The divemaster did ask us to signal him when he asked for our pressure reading. I believe he asked this to me once, which was fair enough as I usually am pretty good with my breathing.

There was no minimum gas figure given for surfacing.

If he said 50 bars, then we could have extended the dive time by more time.
Especially as a lot of the diving was in the shallows.

The other divers also had between 70 to 100 bars when we surfaced. So, I would have thought 50 bars at the safety stop was sufficient under the circumstances. The other divers did seem competent enough. Ok, maybe not with the lack of timing devices. However, I have seen this before, when someone does not have a timing device and relies on others. I am not condoning this, of course.

I really do not have anger issues. Believe me. I am however pretty direct. Sometimes this is not the best way of course. However, I was on vacation and decided not to bring the issue up in case it came out wrong.

Sure I could have asked more questions. As I said, this was my first dive trip so was not sure of the "protocols".

However, I do feel as you mentioned, a minimum gas level should have been the main factor. As we spent so much time in the shallows, a safety stop was basically redundant at that stage.

---------- Post Merged at 10:54 PM ---------- Previous Post was at 10:40 PM ----------

I'm amazed with 100-200 dives this is the first time you've ever ran into this. It's also strange to me that in the dive briefing the DM didn't explain when the dive would be over. It's always typical in my experience for how the dive will end to be discussed in the dive briefing. In your experience with this DM it seems at some point he would have said something along the lines of "At 40 minutes we will do a 3 minute safety stop...."

The thing is, this was the first time I have ever been on such a trip. Here I dive with a small group of buddies and we all know the dive sites well enough, so we generally try to stay down as long as possible (within safety parameters of course).

 

[nimoh]

I really do not have anger issues. Believe me. I am however pretty direct. Sometimes this is not the best way of course. However, I was on vacation and decided not to bring the issue up in case it came out wrong.

In the future, I would recommend that you voice your concerns without fear of them "coming out wrong". If the divemaster takes offence, simply apologize, indicating "that came out wrong".

 

[Mike]

The thing is, this was the first time I have ever been on such a trip. Here I dive with a small group of buddies and we all know the dive sites well enough, so we generally try to stay down as long as possible (within safety parameters of course).

I see.

One thing I keep seeing in these posts is references to ask the DM about how the diving will proceed. In my experience once you're on the boat there is little need to ask the dive master if you can dive your computer. In my experience the dive operator sets the policies and if they are a timed dive operation there is little chance the DM is going to suddenly break all their policies and create a personal dive experience for you. If the dive operator owner happens to be the DM, then of course that opens up more possibilities, but again, the time to ask about the shops dive policies is before you book with them, and its a question to whomever does the booking, and not to their dive masters. Be aware though that I've found many, many dive shops who play dumb to the questions. If a dive op lets you dive your computer and tank they will usually understand exactly what you're asking. The dive ops who run on timed dives for some reason get brain farts when you ask them how they run their dives and you have to ask them more than once and really clarify what you're asking about.

 

[DevonDiver]

Well, my main issue is to insure I have all the correct equipment. To be honest, I only noticed the others did not have the correct equipment when on the boat.

What was your response to that?

There was no minimum gas figure given for surfacing.

There's another thread on that topic currently running - where several divers complain they don't like being given a minimum surfacing pressure - because it limits their dives.

If he said 50 bars, then we could have extended the dive time by more time.
Especially as a lot of the diving was in the shallows.

A dive operator does have to have some sort of policy on dive time - unless it's a privately chartered boat.

Otherwise, people like me would turn up with a CCR and spend all-day, dawn-to-dusk, in the shallows with my camera...

IMHO, 45 minutes is the bare minimum for a dive limit. Most novice/casual divers won't manage that on a standard tank... but the experienced divers will be hampered by it. Again, unless on a private charter or via prior approval when booking, a 60 minute dive limit seems quite reasonable... especially for a busy dive center, if running multiple trips per day, or when there is a substantial transit time to/from the site.

Sure I could have asked more questions. As I said, this was my first dive trip so was not sure of the "protocols".

It's well worth doing some 'expectation management' when booking diving. In busy/resort areas, especially in Asia, it is not uncommon to have set maximum duration dives. As mentioned, 45 minutes is a reasonable minimum, that'd keep most divers happy. 60 minutes is ideal.

Diving in mixed-ability groups is always a loser - because the chances are that someone will get low on air before the time limit, necessitating everyone to ascend. It's nice to negotiate (where possible) for a competent buddy team to spilt from the group when that happens, enjoying the rest of their planned time.

Of course, dive limits are just one side of the story. An unscrupulous divemaster - who wanted to get home early - could just keep their group deeper for longer, foregoing the shallow end of the profile.... burning up customer's air well within whatever max limit had been set, no matter how generous...

However, I do feel as you mentioned, a minimum gas level should have been the main factor. As we spent so much time in the shallows, a safety stop was basically redundant at that stage.

Gas and NDL are equally important factors.

If the dive profile was planned to adhere to tables (PADI RDP), it'd go something like this:

Dive 1 - 60' x 45 mins = PG 'S'
Assuming 1 hour surface interval = PG 'G'
Dive 2 - 60' x 45 mins = A/NDL 34 minutes.
*Cannot proceed with 45 minute desired dives....

So, in that respect, the divemaster is doing you a big favor by 'allowing' the other divers to 'borrow' a multi-level from his computer (i.e. follow like a herd with no ability to control their dive profile).

If the dive operator was to insist that all divers plan and track their own dives,...and other divers used tables, then you could end up with significantly shorter dive times (ave repetitive dive time of 35 mins, based on 3 dives).

Lest not forget how much extension a dive computer can add to a repetitive dive schedule.... it's great... but to reap those benefits you need to have the entire group/buddy pair using them.... Before dive computers became popular/common-use, that's how we all used to dive... go figure

 

[TSandM]

On our first major trip, to Australia, the dive operator had a 45 minute limit on dives. It didn't bother me at the time, because I was very new, but it would sure bother me now . . . A lot of dive operators run on a schedule, and they either use tank size or time limits to stay on that schedule. Because I know that happens, I now want to check and see what the policy is, because like you, I don't want to end up limited to 45 minute dives.

However, before I get in the water to follow a guide (or to guide myself, for that matter) I want to know a few things about the dive plan. I want the basic parameters -- depth and dive time -- because they allow me to know whether I have enough gas to do the dive, and whether I will need to worry about decompression. I honestly can't imagine agreeing to get in the water without an estimate of total dive time, because that's a safety thing.

 

[vladimir]

I am pretty pissed off about the whole situation?

I would be too. Sixty minutes is a more normal limit for that sort of diving, and 50 minutes is the worst explicit time limit I have seen imposed. What was the dive operator's name, if you don't mind (in PM if you prefer)? I want to avoid them.

 

[nimoh]

I would be too. Sixty minutes is a more normal limit for that sort of diving, and 50 minutes is the worst explicit time limit I have seen imposed. What was the dive operator's name, if you don't mind (in PM if you prefer)? I want to avoid them.

although I think 45 minutes is low, I would be more irritated at myself for not checking that out ahead of time.

However, if this restriction were implemented on the dive boat rather than operator policy, that changes things.

 

[rx7diver]

Sure I could have asked more questions. As I said, this was my first dive trip so was not sure of the "protocols". ... The thing is, this was the first time I have ever been on such a trip.

This thread has reminded me of my humorous first dives on Grand Cayman Island. I had only once before dove off of a dive boat, in the Florida Keys a couple of years earlier.

We were diving off East End with Cayman Diving Lodge (remember them?) c. 1992. As the boat was motoring to the site, the DM briefed us that we would be diving so deep (105 FFW?) for so many minutes, followed by a surface interval of so long, and a repetitive dive at a new site for so deep (55 fsw?) for so many minutes. My dive buddy (GF) and I immediately pulled out our tables and began verifying this plan. I glanced up to see all eyes, even the DM's, on us, and no one doing similarly. She and I exchanged glances but continued and finished our check. Actually, the first dive exceeded the limits as determined by our tables! So we agreed we would not dive as deep that first dive, but instead dive the depth determined by our own planning, and enter the water last for the repetitive dive.

During the surface interval I chatted with the DM and learned that we were diving what was called then the "Cayman Profile," a standard multi-level profile that all the operators had been diving for quite some time on that side of GCI. The profile had proven itself to be exceedingly safe.

We all had quite a chuckle at my and my GF's fastidiousness (though we continued throughout the week to check whatever the DM had planned).

Safe Diving,

rx7diver

 

[vladimir]

although I think 45 minutes is low, I would be more irritated at myself for not checking that out ahead of time.

Yeah, that's certainly a good idea, but you guys are all better than me, because it's not a question I routinely ask. It's not a problem I encounter very often, either. The last time was on Little Cayman Island, which sucked because I couldn't change dive operators mid-vacation. I have never encountered it in Asia.

I generally choose dive operators who cater to experienced divers, based on reviews here and in Undercurrent. That usually prevents a lot of problems like this one, which are more likely to crop up with dive operators who cater to new or occasional divers.