missed deco stop

[Crush]

Please note: this post refers to missed deco stops, not missed safety stops.

How were you taught? Please respond with what an agency taught you and refrain from obvious comments like "you shouldn't miss a deco stop" or "get better training."

Let's assume that you aren't doing crazy deep dives where trimix is necessary.

NAUI: In our MD course we were recently taught that if you surface having missed a deco stop, do not re-descend, rather get to land, get comfortable, lay down, breath 100% O2, hydrate, and make sure you are being monitored for DCS. If symptoms appear, go to a hyperbaric facility. If not, no diving for 24 hours.

ACUC: In our OW course I seem to recall that we were taught to re-descend to 10 feet below our missed deco stop and begin to surface, but with an extra, (10 foot deeper) deco stop.

What does PADI teach? SSI?

 

[Diver0001]

PADI teaches a protocol for exceeding NDL's and sorting it out in water ("emergency deco").

Missed stops are treated with 100% O2, observation and possibly hospitalization if symptoms develop.

R..

 

[Thalassamania]

Standard NOAA and U.S. Navy Protocol:

Should a diver realize that they have exceeded the nodecompression
limits prior to reaching the surface, and they do not have access to USN decompression tables to determine required in-water deco time, they should:

• Stop at 10 – 15 fsw for a minimum of 15 minutes or until they reach 300 psi in their cylinder, which ever comes first
• Once on the surface they should be placed on oxygen for a minimum of 30 minutes, observed, and restricted from diving for 12 hours
• If symptoms occur during or after breathing oxygen for 30 minutes, they should be transported (on oxygen) to the nearest medical facility for treatment

Should a diver not realize that they have exceeded the nodecompression limits prior to reaching the surface, or they have insufficient gas to perform in-water decompression, they should:

• Proceed to the surface at a normal rate of ascent
• Once on the surface they should notify the divemaster of their omitted decompression
• If asymptomatic, and the diver can be returned safely to the water within 5 minutes after surfacing, they should dive to the depth of the missed decompression stops and remain for 1½ times the required decompression stop time
• If the diver cannot be returned to the water within 5 minutes, they should be placed on oxygen for a minimum of 60 minutes
• If asymptomatic after breathing oxygen for 60 minutes, they should be observed for a minimum of 12 hours for signs and
  symptoms of DCS and restricted from diving during this observational period
• If symptoms occur during or after breathing oxygen for 60 minutes, they should be transported (on oxygen) to the nearest medical facility for treatment

Note: If a diver is asymptomatic and unable to return to the water to complete omitted decompression, and a recompression chamber is available within 1 hour travel, the diver should be transported to the chamber for possible treatment using USN TT5 or 6

 

[Bubbletrubble]

Here's a scanned Table from the US Navy Diving Manual for managing an asymptomatic diver with omitted decompression stops:

 

[scubadiver888]

Please note: this post refers to missed deco stops, not missed safety stops.

How were you taught? Please respond with what an agency taught you and refrain from obvious comments like "you shouldn't miss a deco stop" or "get better training."

Let's assume that you aren't doing crazy deep dives where trimix is necessary.

NAUI: In our MD course we were recently taught that if you surface having missed a deco stop, do not re-descend, rather get to land, get comfortable, lay down, breath 100% O2, hydrate, and make sure you are being monitored for DCS. If symptoms appear, go to a hyperbaric facility. If not, no diving for 24 hours.

ACUC: In our OW course I seem to recall that we were taught to re-descend to 10 feet below our missed deco stop and begin to surface, but with an extra, (10 foot deeper) deco stop.

What does PADI teach? SSI?

PADI teaches something similar to what you posted for NAUI.

PADI would totally disagree with what you posted for ACUC. They stress not getting back in the water.

 

[AzAtty]

A quite proper response to your question is "you shouldn't miss decompression stops." If you miss a decompression stop, you better have a darn good reason for missing it; something other than poor planning or stupidity.

At the Advanced Nitrox/Decompression Procedures level, TDI teaches the Navy protocol for omitted decompression stops, provided the diver is asymptomatic and can return to the water within one minute.

At the trimix level, TDI teaches you to back up your main dive plan with contingency plans for blown depth, time, and deco stops.

PADI does not teach decompression diving at the OW level, so there's no such thing as a "decompression stop" in PADI OW parlance. PADI teaches the following for a blown NDL at the OW level:

a) If a diver exceeds a no decompression limit by five minutes or less, the diver should ascend no faster than 60 ft/min, perform an eight-minute safety stop at 15 feet, then slowly surface and stay out of the water for six hours.

b) If a diver exceeds a NDL by more than minutes, the diver should ascend no faster than 60 ft/min, perform a 15 minute or longer safety stop at 15 feet (gas supply permitting), slowly ascend and stay out of the water for 24 hours.

 

[pittyyofool]

thanks Thalassamania, you saved me a whole bunch of typing. I learned what he said.
I will add to that,
If you realized the missed deco stop before you reach the suffice and you have an ample gas supply.
redescend to the missed stop and start all of your deco stops over staying at the missed stop for 1.5 times the original stop length.

 

[Davidstealey3]

Thalassamania & pittyyofool got it right. use the navy tables for this. you can find them a lot of places on the internet. make yourself a little copy and laminate it. carry it with you.

i think the emergency deco comment should be relabeled " in water decompression". they have a chart for this also.

now i did find my deco procedures book from TDI with the Omitted Deco procedures and it reads as follows

if a diver surfaces, for whatever reason, and misses a mandatory deco stop there are several factors which must be taken into consideration. First of all, the condition of the diver and/or the enviroment may make it impossiable to return to the water. if the diver exhibits ANY symptoms of DCS recompression is the only pratical choice.

the most common course of action for a short time misses will be to put the diver on oxygen and monitor their condition. further diving should be curtailed by the diver for 24 to 48 hours minium

if the diver and the conditions allow, the US Navy has an alternative emergency technique

if the diver ascends from 20 FSW or shallower, feels well and can return to the waterin 1 minute, descend to the required stop depth and continue with the planned deco. the 1 min is added to the stop time.

if the diver ascends from 20 FSW or shallower and is not able to return to the water in 1 min but remains free of symptoms, the diver can return to the stop and multiply the STOP TIMES by 1.5

if a diver ascends from a stop deeper then 20 FSW and is free of symptoms, a stnd by diver is available and the water conditions permit:
return the diver to the depth of the first stop
follow the sechudle for all stops 40 FSW or greater
use 1 min between stops, not 20 seconds
multiply the 30,20, and 10 FSW stops by 1.5

in any case continuing or placing the diver on 02 at the surface for at least 30 minis a good measure

hope this helps you

 

[Bronson]

The PADI standard is noted above. Best to not go into decompression status and if so pay close attention to your computer on stops.

 

[Crush]

Thanks to all the respondents.