BC Power Inflator, do we really need it ?

[elan]

This question came to me after working harder on my buoyancy skills and starting diving the no BC configuration. At this point I have managed to deal with buoyancy changes that breathing out 50 cuf of air make, which is approx 4lb. The question came to my mind right after is if I'm weighted properly and do not have to put and dump all those huge amounts of air into the BC would not it be more safe not to have the hose connected at all and just inflate the thing orally, one will not need to do this many times anyways. This will eliminate the risk of the runaway inflator altogether. I know some people dive this configuration.

It would be nice to hear come comments from our more experienced members. I do not see any great risk here but can see a huge mitigation strategy especially when diving extremely cold water < 38-40F.

Thanks a lot.

 

[Teamcasa]

...and just inflate the thing orally, one will not need to do this many times anyways. This will eliminate the risk of the runaway inflator altogether. I know some people dive this configuration.

It would be nice to hear come comments from our more experienced members. I do not see any great risk here but can see a huge mitigation strategy especially when diving extremely cold water < 38-40F.

Thanks a lot.

Why? Good maintenance and careful pre-dive inspections prevent runaway inflations.

I have no issue with the minimalist divers not using BC's but for a significant number of recreational divers still like the convenience of a power inflater.

 

[redacted]

I don't think it is really a safety issue; but no, you don't need a power inflator. With reasonable maintenance, they are just not a big problem. But it is a handy convenience especially when you are descending a little to fast and trying to avoid the crash landing.

Heck, in warmer water the entire BCD is more a convenience than a necessity.

 

[Cave Diver]

This question came to me after working harder on my buoyancy skills and starting diving the no BC configuration. At this point I have managed to deal with buoyancy changes that breathing out 50 cuf of air make, which is approx 4lb. The question came to my mind right after is if I'm weighted properly and do not have to put and dump all those huge amounts of air into the BC would not it be more safe not to have the hose connected at all and just inflate the thing orally, one will not need to do this many times anyways. This will eliminate the risk of the runaway inflator altogether. I know some people dive this configuration.

It would be nice to hear come comments from our more experienced members. I do not see any great risk here but can see a huge mitigation strategy especially when diving extremely cold water < 38-40F.

Thanks a lot.

It's a tool and like all tools it has it's place. Early pioneers in diving didnt have bouyancy compensators, some even used gallon beach bottles slung under their arms to control bouyancy.

To me at least, it comes down to a matter of safety. Can I orally inflate a BC? Yes. But one thing to keep in mind is that a diving accident is rarely the result of a single event. Typically it is a chain of events that starts with one thing and escalates until the problem becomes unmanageable.

In an out of air or panick/emergency situation, would you really want to be taking a reg out of your mouth so that you can orally inflate your BC? That is just adding task loading and complexity to a situation where none is called for. The loss of an LPI hose doesn't come near to outweighing the gain of having one, at least in my opinion.

Once you get your bouyancy dialed in, you'll likely find that it takes little to no adjustment during a dive. Kind of set it and forget it. The runaway inflator issue can usually be avoided altogether by proper maintenance , but easily managed if it does occur. After your bouyancy is right, you'll notice pretty quickly if you're getting a small leak into your BC causing you to become positve. A large leak is easily handled by quickly popping the LPI hose loose, provided you're practiced in doing this skill.

On the other side of the coin, I do often practice orally inflating my wing fairly often. I've also been known to disconnect the LPI hose during a dive and use strictly oral inflation, just for the practice. I prefer to keep up with skills that I'll hopefully never need in order to keep them smooth and automatic and I prefer to have more options for dealing with problems during my dives rather than less.

 

[TSandM]

Unless you are one of those people who has a bungied backup regulator so finely located that you can pick it up without your hands, orally inflating a BC is pretty much a two-handed process -- which means you realistically can't do ANYTHING else while you are dealing with it. You can't really manage a reel, or an SMB, or assist a buddy. I'll trade the ability to do those things for the very rare necessity of disconnecting the LP inflator hose underwater (which I have had to do once, because of a slow leak).

 

[scubafanatic]

...so, let's say, for example, you're 'working out' underwater, swimming into a current, or otherwise exerting a little effort...then you're 'hit' by a 'downcurrent' and suddenly losing 'altitude', and you wanna squirt a fair amount if air into your wing 'NOW!"...and at the same time you'd really like so be able to suck on your reg without interruption......are you seeing where this example is heading ? ? ? ...if you think about it a minute, I'm sure you can think of a few bazillion reasons/senarios where having no BC hose connected is a very BAD idea ! ! !

 

[redacted]

...so, let's say, for example, you're 'working out' underwater, swimming into a current, or otherwise exerting a little effort...then you're 'hit' by a 'downcurrent' and suddenly losing 'altitude', and you wanna squirt a fair amount if air into your wing 'NOW!"...and at the same time you'd really like so be able to suck on your reg without interruption......are you seeing where this example is heading ? ? ? ...if you think about it a minute, I'm sure you can think of a few bazillion reasons/senarios where having no BC hose connected is a very BAD idea ! ! !

If you need to change depth quickly, I suspect that fin kicks will be a lot more effective than trying to use your BCD for propulsion. And it will be a lot easier and quicker stopping when you get to the depth you want to be at by stopping kicking than by adjusting the gas in your BC.

 

[Cave Diver]

It would be nice to hear come comments from our more experienced members. I do not see any great risk here but can see a huge mitigation strategy especially when diving extremely cold water < 38-40F.

This was one part of your question that I didn't address in my original post. I think I see where you're going with part of this thinking and that is the reasoning that the rapid filling of a BC in cold water can lead to a free-flow from first stage freeze up.

I don't have much experience in extreme cold water diving, but I would try to mitigate the risk of such by:

1) making sure my regs had cold water service kits
2) carrying some sort of redundant air source, whether it is doubles, or a slung stage, etc.
3) choosing an inflator that has a slower fill rate

Remember, diving is not about taking risks, it's about managing those risks that are inherent to the sport as best we can.

 

[Cave Diver]

If you need to change depth quickly, I suspect that fin kicks will be a lot more effective than trying to use your BCD for propulsion. And it will be a lot easier and quicker stopping when you get to the depth you want to be at by stopping kicking than by adjusting the gas in your BC.

I believe he was talking more about unusual situations such as the rapid downwellings that many people have experienced diving the walls in Mexico rather than just a normal depth change. People that get caught in such a situation need to establish positive bouyancy rather quickly and kicking by itself may not be sufficient to do so. Then there is the additional problem of potential for CO2 buildup while deep, etc.

 

[elan]

Thanks for all your good points. I think with the maintenance one can prevent it happening but with the cold water and elevated chances of the inflator malfunction due to freezing or 1 st stage freeflow makes me thinking about that. Now if we talk about freezing cold water we assume that the person will have a another buoyancy device that is a dry suit that can be used as a temp buoyancy device in case an instant lift is required. This can also freeze open but at least in case when a separate bottle is used for inflation the chances are lower as the reg is not loaded at all. Cave Diver I cannot actually agree with you that the issue can be managed easily. while for warm water divers that can be a breeze in cold water most likely it will mean the connector freezes up and in thick gloves there are much less chances to disconnect the connector as of my understanding.

How would cold water affect this situation in your opinion ?