Decompression Stop Guidelines - What we have to do if got deco alert?

[IDCBali]

Source: IDC Internship Blog - Blue Season
Emergency Decompression Guidelines
Scuba diving may be a fun and exciting sport but it’s not all just about fun and games. To really enjoy and excel at scuba diving, you’ll need to undergo training, which will also ensure you and your group’s safety. During your Divemaster course in Bali, you’ll learn all about decompression, which is an integral part of diving that you must truly and completely understand.

There may be times when you hear of divers complaining of a bad experience due to decompression during a dive, which led to massive discomfort and pain. It is important for every diver to know and understand about decompression, potential decompression problems and how to handle emergency decompression stops during a recreational dive.

Decompression Underwater Sign
Firstly, what is decompression and what is an emergency decompression stop? If you’re an experienced diver, you’ll already be familiar with these terms but for the sake of safety, let’s recap. Obviously when you’re diving, you’re relying on compressed air. Breathing compressed air causes nitrogen gas to accumulate in your bloodstream and absorbed into your body, however it will slowly disperse when you begin to ascend due to decrease in pressure. However, if you were to ascent rapidly, the nitrogen gas in your system will turn into gas bubbles, causing decompression sickness.

Events such as these may happen due to a variety of reasons; you may forget to check your dive computer, perhaps you got distracted and stayed underwater for too long or you may have gone too deep. When these cases occur, you will need to perform an emergency decompression stop. Secondly, understand the term “no-decompression limit” also known as NDL. This refers to the time limit for the amount of time a diver can stay at a given depth. These limits vary from dive to dive, depending upon depth and previous recent dive profiles. Please bear in mind that a diver should never exceed a no-decompression limit without specialized training in decompression procedures.

Every diver knows that mistakes can happen and you might stray too deep or stay too long underwater. When such situations arise, you might not immediately know the danger you are putting yourself in. It is always better to avoid exceeding or diving up to the no-decompression limit. However, if you find yourself in such a situation, you will need to know how to react to a safer diving experience. Here are some simple guidelines to help you during emergencies:

Emergency Decompression Guidelines

• When a no-decompression limit is exceeded by 5 minutes or less, your stop should be 8 minutes at 15 feet and make sure you remain out of the water for 6 hours before the next dive.
• When a no-decompression limit is exceeded by more than 5 minutes, your stop should be at least 15 minutes at 15 feet and you should stay out of the water for a minimum of 24 hours before diving again.

Make sure you have these emergency decompression rules well noted on the back of your computer or on a slate. This is because remembering the rules may not be possible in an emergency situation. It is important to ensure the information is easily accessible in case of an emergency.

Monitoring Your Emergency Decompression Stop

To be fully in charge of your dive, especially when there is the need for an emergency stop, always have prior knowledge about scenarios that can lead to such situations. You might forget to check your dive computer or it may fail, thus misleading you. If the timing device has malfunctioned, you might be forced to count out the minutes.

If you find yourself alone and with no dive computer, you should wait at the stop depth as you exhaust the remaining tank of air before ascending slowly. In case all devices malfunction and you don’t know the depth or the dive time, you will have to rely on experience to estimate your depth and ascend.

While no diver expects to ever have to do an emergency decompression stop, it is always advisable to understand and memorize these guidelines. Remember, it is better to carry out a correct emergency decompression stop than to fumble about when underwater. Be sure to participate in the right Divemaster Internship program while you’re in Bali, to learn how to face and excel in any underwater condition. I

 

[The Chairman]

I have issues with a lot of what you wrote.

• It's not an "emergency deco stop". It's just a mandatory deco stop.
  • Just say "NO!" to needless drama!
• If you're diving with a PDC, then please, please follow it.
  • Your 8 or 15 minute random stop may not fulfill your deco obligation.
  • Evaluate your gas supply as you decompress. Drowning will ruin an already bad day.
• If your deco was unplanned, sit out for the rest of the day.
  • There's just no excuse for accidental Deco
  • Take the time to evaluate your diving habits.
• If you missed any deco time:
  • Go on oxygen for a minimum of 20 minutes or 5 times the amount of deco time you missed, whichever is greater.
  • Monitor yourself for signs of DCS.
  • Stay out of the water for at least 24 hours or whatever your doctor suggests.

 

[DevonDiver]

If you're diving a computer, why would you follow rigid tables-based emergency deco guidelines??

Every dive computer on the market will provide you with a workable emergency deco ascent profile to provide safety if you accidentally exceeded a no-stop limit.

What amazes me is the high percentage of divers who completely fuddled when confronted with emergency deco info on their computers.

This isn't DM training... this should be taught at OW level. It's beginners who are more likely to lack situational awareness and exceed no-stop limits.

Fair enough, teach the tables procedures as a general MINIMUM.... but also teach divers how to use their computers... and that includes emergency deco mode.

 

[Lorenzoid]

Ha. Even Andy refers to it as "emergency deco." I do like Pete's point, though. No need for drama; just do what the computer is instructing you to do.

 

[boulderjohn]

The article leading this thread disturbs me quite a bit. In fact, I find it a bit frightening. According to the dive profile, the OP is a DM and instructor training facility. I assume, then, that this is the kind of training a prospective instructor would get at your facility. It blends the old PADI training with the new PADI training, giving a little of each, but making it completely wrong in regard to current PADI instruction.

Current PADI practices allow the student to take the course using either the RDP (or eRDPml) as the guide, the way it was done for decades, or they can take the computer version of the course. The article talks about the diver using a computer (and forgetting to pay attention to it), but then tells the diver to use the procedures that go with the RDP rather than the computer. That makes no sense.

The current PADI computer course teaches students to be familiar with their computer's method of guiding a diver through emergency deco and follow those procedures if needed. They do NOT tell the diver to follow the old RDP methodology. This can be found on pages 227-228 of the current PADI manual (English language version). Is it possible that an instructor training center does not know this?

 

[The Chairman]

Even Andy refers to it as "emergency deco."

Some people like drama! I certainly don't. Keep it in perspective. It's not the end of the world, so don't treat it like that. The drama can only increase your breathing rate and lessen your chances of not being hurt. I've never heard the term "emergency deco" and I'm OK with that.

The article leading this thread disturbs me quite a bit.

Indeed.

 

[TrimixToo]

I have issues with a lot of what you wrote.

• It's not an "emergency deco stop". It's just a mandatory deco stop.
  • Just say "NO!" to needless drama!
• If you're diving with a PDC, then please, please follow it.
  • Your 8 or 15 minute random stop may not fulfill your deco obligation.
  • Evaluate your gas supply as you decompress. Drowning will ruin an already bad day.
• If your deco was unplanned, sit out for the rest of the day.
  • There's just no excuse for accidental Deco
  • Take the time to evaluate your diving habits.
• If you missed any deco time:
  • Go on oxygen for a minimum of 20 minutes or 5 times the amount of deco time you missed, whichever is greater.
  • Monitor yourself for signs of DCS.
  • Stay out of the water for 24 hours.

What he said. Especially this part: "There's just no excuse for accidental Deco."

John

 

[The Chairman]

What he said. Especially this part: "There's just no excuse for accidental Deco."

That's the part that really bothers me here. I can't remember ever going into 'accidental' deco, just as I have never run out of air since I started using an SPG. If you're too broke to pay attention, then sky diving and scuba diving aren't for you.

 

[pepperbelly]

That's the part that really bothers me here. I can't remember ever going into 'accidental' deco, just as I have never run out of air since I started using an SPG. If you're too broke to pay attention, then sky diving and scuba diving aren't for you.

The only time I came really close to running out of air was when I forgot to reset the reserve lever on my "J" valve. Thank goodness air was added as I ascended.

 

[dmaziuk]

Ha. Even Andy refers to it as "emergency deco."

My reading is that by definition of a no-stop dive, a mandatory stop is considered an emergency. My PADI OW manual does call it "Emergency Decompression" on p. 218.

(I also think that's too much drama and that one should never get there by "accident".)