baffled by Suunto D4i info while diving vs dive log

[Belzelbub]

That’s SUUNTO.

They preferably for you to wait even longer, up to 100 hours, as stated in page 82 of D4 manual:
“When the battery is changed, all nitrogen and oxygen uptake data is lost. Therefore, the no-fly time shown by the computer should have reached zero or you must wait for 48 hours, or preferably up to 100 hours, before you dive again.”

I don't have a Suunto, but I recall reading here from a user that the no-fly countdown didn't start for him until after the 48 hour lock was completed.

 

[Dan]

I don't have a Suunto, but I recall reading here from a user that the no-fly countdown didn't start for him until after the 48 hour lock was completed.

I won’t bother with what SUUNTO recommend in that case. I’ll go by what DAN recommend.

Flying After Diving

To avoid decompression sickness, divers should wait before flying. Read the DAN studies to learn more about current guidelines.

dan.org

 

[Centrals]

I won’t bother with what SUUNTO recommend in that case. I’ll go by what DAN recommend.

Flying After Diving

To avoid decompression sickness, divers should wait before flying. Read the DAN studies to learn more about current guidelines.

dan.org

The lock up could be due to missing deco stop or something serious other than any trivial mistake.
24hrs+.

 

[inquis]

I have heard that the Suunto is conservative. I know we used to joke about how the thermometer always rounded down

Unfortunately, it's NOT always conservative. For a clean dive, RGBM has the same NDL as Buhlmann+GF x/85 at 40 ft (Shearwater's "medium"), but GF x/98 at 90 ft (quite liberal). It's on repetitive dives that RGBM earns it's conservative reputation.

If juggling two algorithms, you really need to look at both *during the dive*, rather than just having it along as insurance against missing successive dives.

 

[Dan]

The lock up could be due to missing deco stop or something serious other than any trivial mistake.
24hrs+.

From DAN article:
“Medical Society (UHMS) recommended curtailing all diving within 24 hours of a flight and up to 48 hours following a decompression dive.”

If it locks out because you surface a few minutes before it clears out the D10 (we are dealing with recreational non NDL diving here, not technical diving), then the No fly time would be that remaining D10 time + 48 hours, I would think, not the 48 hours + 48 hours = 96 hours as SUUNTO would require you to be on the ground before clearing the No Fly time.

 

[dmaziuk]

I'm home now and looking at the dive log in Subsurface. There are yellow warning triangles, but the NDL is listed as 120 min. Some of the triangles have below floor begin or end and ceiling begin and end, but they're on the same triangle so it doesn't make sense.

Yellow triangles are momentary exceeding of the safe ascent rate. The keyword here is momentary: it can happen e.g. when you raise your computer hand while inhaling, or some such. The computer will only sound the alarm when they become continuous, averaged over some period of time (and subsurface will draw red triangle there), but the log records raw data at a point in time. And you get those bogus yellow triangles.

 

[tursiops]

Not everyone wants a $1000 computer where 50% of purchasers have to return it for repair.

Aside from the fact that the problem you allude to seems to have been solved, your statistics are rather an exaggeration! I get it that you think not everybody needs an expensive computer. I don't get why you have to make sh** up to "prove" your point.

 

[eab]

I won’t bother with what SUUNTO recommend in that case. I’ll go by what DAN recommend.

Flying After Diving

To avoid decompression sickness, divers should wait before flying. Read the DAN studies to learn more about current guidelines.

dan.org

Same for me. 24 hours no matter how few or shallow I've been.

 

[eab]

Unfortunately, it's NOT always conservative. For a clean dive, RGBM has the same NDL as Buhlmann+GF x/85 at 40 ft (Shearwater's "medium"), but GF x/98 at 90 ft (quite liberal). It's on repetitive dives that RGBM earns it's conservative reputation.

If juggling two algorithms, you really need to look at both *during the dive*, rather than just having it along as insurance against missing successive dives.

Thanks. Yes, I do check them both throughout the dives. Normally I'm in <30 feet of water doing coral nursery or outplanting dives. It's been a while since I've been deep enough to require a safety stop.

As a result of all this, I am now better aware of Subsurface and my Suunto computer.

It's been a long time since I studied the different algorithms. Probably time to dust off those brain cells too.

 

[eab]

Yellow triangles are momentary exceeding of the safe ascent rate. The keyword here is momentary: it can happen e.g. when you raise your computer hand while inhaling, or some such. The computer will only sound the alarm when they become continuous, averaged over some period of time (and subsurface will draw red triangle there), but the log records raw data at a point in time. And you get those bogus yellow triangles.

So true! I was fighting with a leaky mask one dive and it was yellow triangles all over. The dive was about 25 feet max and maybe 40 minutes, and the dive log looked hilarious!