OSTC SPORT AND SAFETY stops

[guyloup]

I have been diving with my new OSTC sport last two weeks. It seems that the OSTC has been giving me a 3 minutes safety stop on the first 10 dives or so. Then I made a dive with a deco of 5 minutes at 4m ( was installed as the shallowest deco stop by myself) but after these 5 minutes, there was no addition of any safety stop. OK?

After that I am not 100% sure but I have the firm impression that no safety stop was required anymore, even if I changed nothing in terms of settings on the OSTC.

I have the following questions:

How come that I am getting safety stops in the first few dives and not afterwards.

2. Am I right when I think that deco stops ( like the 5 minutes @ 4 meters ) do not include the safety stop? But then, why not add a safety stop option that would be there to respect or disregard.

I am a little lost here. Can anyone help.

Appart from that, great computor, but some data are impossible to read without glasses underwater.

[sailor]

Hello,

safety stops are only for "no deco" dives.
Once your dive turned into a deco dive there is no more safety stop as you have a deco stop already.
You can control the safety margin of the decompression calculation by the setup.

To sum it up, when you have to do a deco stop the safety stop is already included in the deco stop.

Reiner

[guyloup]

Thank you Reiner.

So I understand everything about the deco dives.

Now lets focus on the non deco dives. How come that my last few dives, who did come very close to the NDL limit but did not go into deco, did not show any safety stop. I have seen it many times in my last few dives: a safety stop demanded by my backup ( cressi computor ) but not by the OSTC Sport.

Is this possible or was I narcosed

I am really wondering. Any idea about what could have happened? I happened several times: safety stop while close to the surface ( 5 to 4 m) on the Cressi and nothing seen on the OSTC.

[sailor]

Hello,

I can't answer that question.
Make sure to use the "Deco Mode" and not the "Apnoe Mode".
Maybe the Cressi is more sensitive showing a safety sop more early.

Reiner

[guyloup]

Thank you. I am sure I am in deco mode since the NDL is given I read in the manual : Safety stop If you go diving within the no deco limit
(NDL) and have no decostops, there
will be displayed a safety stop of three
minutes in five meter. It is shown as a
countdown to the split second.

So when you say that the Cressi could be more conservative. Do you have an idea about the conditions ( depth, time, compression group ) that would "trigger" the safety stop.


Anyway, I will take notes for the next dives. But sadly, this will be only in November. So you confirm: safety stops CANNOT be suppressed one way or the other with any setting. This is what I wanted to know.

[guyloup]

Just one tought. I watched the following video https://www.youtube.com/watch?v=KoFBKk0sSc0. This was comparing the OSTC Sport with the Xdeep black. What is clear at the end, is that the safety stop is visible on the screen of the Xdeep and not on the OSTC @ 5,1m. Therefore my question:

At what level is the safety stop visible on the screen?

Whould it be possible that if one stay for 3 + minutes slightly below the 5 meters mark that the "safety stop" would never be visible.

That would be the reason for my observation

[HKu]

I think I may have to correct you. Starting from 8:17 you can see the 5m safetystop. It's in yellow in the bottom right, above the NDL.
It's just not visible constantly, but looks as if it cycles.

[guyloup]

Dear HKU,

thank you for your remark. I have seen the video again and I am afraid, I do not share your conclusions.

Video:

8:07 depth 5.1m nothing visible about the safety stop while the Xdeep has
some.

8:17 depth 4.8m both show some safety stop

8:24 depth 5.2m again no indication of a safety stop on the OSTC but well on the xdeep.

8:36 depth 4.9m déco stop on both.

after that, the depth is just above the 5m mark, but you can see that the OSTC is lagging behind the Xdeep with some 30 seconds.

My guess and my question is the following: it seems that the safety stop appears only above 5m. This is consistant with the instruction for use ( look page 75). But does this mean that the safety stop count down is ONLY active ABIVE 5m, or does it continue if you are, let say, at 5.5m.

[Clownfish]

Obvious that the OSTC only counts safety stop when shallower than or equal to 5.0 metres. If you look at one spot, there is only one second difference between the safety stop countdowns. Later, the OSTC is about 30 seconds behind. This means that the countdown stops when deeper than 5.0 metres. This similar to the default depths on the OSTC 2N. Can you change the depth that it starts from on the 3?

[heinrichsweikamp]

Hi,

The safety (3min) stop in the "Sport" is active when:
a) The dive is deeper then 10m
b) there is no deco when passing the 10m
c) the depth is between 5 and 3m

It is paused when going deeper then 5m, reset to 3min when going deeper then 10m and cleared above 3m.

Regards,
Matthias