What Happens If A Hose Blows? - Scuba Tech Tips: S06E16
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- เผยแพร่เมื่อ 8 ก.ย. 2024
- Alec shows us what happens when you cut a High Pressure and Low Pressure hose. Answer, not much, and it is hard to do.
Don't try this at home divers.
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Kindness is the nobility of intelligence, I love your channel.
Thank you very much Rayane.
On the low pressure hose test, you should have attached the SPG and timed how long until the cylinder was empty. I know at 1 atmosphere it's not the same as at depth but it would give some idea how much time a diver has to surface.
I prefer the 'grab my buddies spare' method but you could try that option too.
The Bob Ross of scuba
I'm hoping that's a compliment.
Thanks. Alec
I had a quick look but didn't see anyone mention it.. You can easily kink the low pressure hoses to save your air if this happens, probably wouldn't work with the hp one tho. You can entirely stop the leak doing this as long as you're holding it. Love your tech tips videos, I'm slowly working my way through them, thanks Alec!
Thanks for the tip.
A
This happened to me at 10 meters down today, and I ran out of air almost immediately. Thank goodness the noise was so loud that everyone in my group heard it and gathered around me quick. There were splits in both hoses (dive centre equipment) and a massive bang
Oh yes the 'bang' does get ones attention. Kevin had a dive computer 'blow up' just as he stared down. He said knowing what we showed made him much more comfortable handling the problem and a slow ascent was done. Thanks for sharing Van.
A
I only recently found your channel and have learned quite a few things (I've been an active diver since '83). I once had bubbles streaming out the entire length of my HP hose and I was quite nervous for the rest of the dive (a DM led dive in difficult conditions in Palau so aborting at that point would have been difficult) - had I already seen this video I could have just noted it and enjoyed the rest of the dive knowing it wasn't that big a deal. A few years ago I saw a DM's o-ring burst during a dive (?) and it looked like a different situation altogether...no restriction in the valve and HP air coming out - he was engulfed in bubbles as you might expect. The DM handled it calmly, and it was nice to see all the divers start to rush to him ready with their octopus. After the dive he told us it wasn't that big a deal - he still had air to breathe. I could only guess he'd experienced that before as I don't see how it would be possible to calmly handle that the first time it happened!
The more you dive, like a DM in the Caribbean, the greater the chance you experience some sort of failure, hose, o-ring, LPI, dropped belt and so on. Glad my channel helps you feel more in control should this happen to you.
A.
There is so much I don't learn because I am not surrounded by a diving community here in the foothills of NC. I'm glad I subscribed. Thank you for sharing your knowledge and experience.
Thanks for watching Vic.
Alec
Brilliant as always Alec, really enjoy your videos.
Thanks for watching JD.
Alec
I had a low pressure hose burst once at the beginning of a dive (full tank). I went from 3200 PSI to 750 PSI in about 45 seconds. The ocean around me looked like a carbonated beverage. While it sounded like a .45 being discharged next to my head, to my GoPro it sounded like a tiny “pip”. Video of the incident was posted on YT.
It’s my understanding a high pressure hose failure will result in a stream of small bubbles and your tank wouldn’t empty nearly as fast.
HP hoses have very small openings as only pressure needs to pass down the hose. Air will come out but not as fast as a larger LP hose. Glad you made it back.
A
@@AlecPeirceScuba_SeaHunter can confirm 🤣 60 seconds of excitement
This is very informative.
Glad it was helpful!
I shared your video to a PCP compressor topic.
Love ur humor in every post...
Whew! Thanks Richard.
Some people just don't get British humor (from my Dad).
Take care.
Alec
I had a high pressure hose blow on me. I just posted this on your video about pony bottles. Probably why this video was recommended.
My worry would be it happening on a vacation, when you are doing drift diving. Surfacing early during one of those could end up with you being lost. On vacation they usually tell you to surface as a group. A blown hose you wouldn't have time to tell the divemaster you have an issue. My plan is every 4-5 years I'm just going to replace the hoses.
It is rare to have a HP hose blow but as you experienced, you have time to make a slow, safe ascent. When drift diving, it is expected for every diver to have a SMB to signal on the surface. If you can signal the guide you're going up, fine, if not, you surface anyway. Remember before reaching the surface to look around and listen for moving boats. Key point is a burst hose is not a panic event as you can surface safely and orally inflate the BC then wait for a dive boat.
@@AlecPeirceScuba_SeaHunter I agree with this. My worry is the dive boat usually waits around where the dive should end. With heavy current on the surface you can get pushed far away.
My hose bust, when I was helping with a rescue class. Always wondered if the instructor cut my hose.
Hi Alec, hope you're all well.
I can't recall if you made a video about pony/bailout/bcd cylinders etc.... .3 litre right up to the 3 and 7 litre variants.
Our compliments of the season to you all..
Thanks Peter. Best wishes to you and yours as well - this is from Africa.
Good idea for a Tech Tip.
Alec
Oh my, now that must be a nice warm dive in Africa. Unless you're sand surfing. We have just had a snow forecast for this evening, it's currently 2˚C (36˚F) here. Are you there for Christmas or Thanksgiving or just for sunshine?
Well I do hope you have some great footage of your adventure, it definitely sounds exciting... I wish you a pleasant journey home and I look forward to catching up. It's been a hectic few months here which I'll share on the other side.
All the best and take care for now.
Peter
Alec, another excellent video. I have had a HP hose fail. I knew from my tec training about the small bore. As you said I had plenty of time to come to the surface and do a safety stop and came to the surface with very little drop in pressure. Very useful video.
Good to hear your training and understanding of hoses let you calmly react to a serious problem. Thanks for watching.
Alec
I witnessed a HP hose popping once on a diving boat. Make a noise comparable to a .22LR being fired. That wakes you up!
Good thing there are air restrictions on the SPG port and hose huh! Still noisy though.
Thanks for watching.
Alec
This is why I own my gear and service it regularly. As I've learned, air is sort of important.
Air is slightly important, looking cool while breathing is better.
A
I had what I thought was a blown hose from my right hand post at 50m - Twinset diving. I did a valve shutdown and ended the dive breathing off my other regulator. When I surfaced and inspected the regulator it turned out that one of the LP inflator hose for the second bladder in the wing had come loose and nothing seriously wrong. So it always pays to check that no hoses have loosened whilst traveling when putting your gear together. This was also the fourth dive on the trip, so I would have thought any issue would have manifested itself during the first dive, but not so.
Glad to see training and calm thinking kept you safe. Thanks for sharing Gordon.
Thanks a lot Alce for your great videos ... it happened to me on last diving trip Luckily I was just start the dive at around 5 meters depth only
Good experience.
Thanks for watching.
Alec
cheers Alec, great educator, many thanks from the Emerald Isle
Glad you enjoyed it and love to visit Ireland some day. Too cold for diving but you have some interesting 'refreshments' I want to try.
Alec Peirce the science guy!
I was science teacher for several years and really enjoyed it.
I'll take this as a compliment.
Thanks. Alec
WOW! That brought back memories. I had a high pressure hose blow during a pool session. It blasted a hole in a hose protector and scared the crap out of us.
I'm guessing that was a while ago, before restricted orifices.
It used to happen quite often. If you look carefully at a high pressure hose you'll find a series of tiny holes running the full length on one side. They are there to stop the hose 'blowing up'. If the hose starts to leak the air just comes out like an aquarium diffuser.
No more explosions.
Alec: I was on a dive boat when the yellow hose on a diver had the regulator or mouth piece come loose. the hose whipped around and hissed quite a bit. It certainly startled everybody.
The longer the hose the more likely it will thrash about.
There's no real danger though.
Alec
Useful. I was diving last week in Gozo with my daughters and one of them was using rented gear from the dive operation guiding us. About 15 minutes into the dive I noticed a stream of small bubbles started coming from her depth/pressure gauge console. I pointed it out to the guide, but he didn't seem concerned and we continued the dive (for another 45 minutes). I stuck close to my daughter just in case. Luckily we didn't turn the Blue Hole into a jacuzzi.
I did wonder how long I'd have to get my octopus over to her if it did get a bit too bubbly.
It was probably a weak swivel pin. I cover the repair of that in one of my videos. They are subject to a lot of wear and tear.
The good news is, that while it must get fixed, it is not usually a reason for serious concern on a shallow dive.
Take care.
Alec
@@AlecPeirceScuba_SeaHunter Many thanks for taking the time to answer. Enjoy your videos. Very useful.
Maybe you could have mentioned the different thread sizes of the hoses to highlight that they can't get mixed up - great video Alec, love to see your enthusiasm, and your love of the sport. When can I collect my regulator!!!
Regulator? Remind me. I'm old.
I'm certain that I have mentioned that regulator hoses now have 2 different threads to keep the low pressure and high pressure separate. Check back in Tech Tips for references to hoses.
Years ago when they were the same, it was a problem - blown hose or inaccurate SPG.
Alec
If you ever have to cut a high pressure hose again bolt cutters would work better. Nice job describing the different hoses and expectations of what to expect if we have a hose burst.
Right! Bolt cutters. I didn't realize how tough the hoses are.
Thanks for watching.
Alec
That was cool always wondered about that. Wonder if you could "kink" the hose and make it stop flowing?
Maybe the Low Pressure hose will stop flowing is you kink it sharply. The pressure is only 150 psi and you can stop or at least slow the flow.
I doubt you can stem the flow from a high pressure hose at 3000 psi. I'm not sure but I'll try it and let you know.
Good thinking.
Alec
So Alec, What if you had 2 tanks? Would the regulator shut one side off and continue to use the second tank or would both of them lose pressure? I would think that there would be a shuttle valve of some sort to shut air off from one tank and use the other tank by monitoring the hi and low pressure of each tank. Besides that hi pressure hose is bullet proof. The low pressure hose seems more dangerous to me. Hi volume, NO AIR to the mouth piece. Thanks again, great video. Keep up the good work.
On a twinset, both tanks would empty (quickly). You have an isolation valve between the two tanks and we do safety drills to practice reaching this and being able to shut it down in seconds. Then shut down the pillar valve in the hope that you isolate the problem and save a bit of gas!!
Highpressurehose vs lowpressurehose at 13 feet: th-cam.com/video/MjWIsZXL_hE/w-d-xo.htmlm12s
Nice video. Another example of cutting Highpressurehose vs lowpressurehose - th-cam.com/video/2-dhP_jSO6I/w-d-xo.html
This just happened to me. Going to Mexico in a few days. Hope i can get it fixed!
Can always try duct tape!
No worries, I won't try this at home. I will try it underwater at my local lake.
For a real out of air scenario, don't cut your hose!
@@AlecPeirceScuba_SeaHunter I'm kidding. I wouldn't do something that stupid.
@@AlecPeirceScuba_SeaHunter If anything, I would just hold the purge valve and breathe off the bubbles for practice like they teach you in training.
Very interesting!! Thank you.
Glad you enjoyed it!
You could have poked your eye out...LOL
That was a good movie huh!
Alec
Absolutely LOL
Hi, a month or so ago the connector on my low pressure inflator came apart. I was about 20 m underwater at the time. It looks worse than it is luckily. I tried to tie a knot in it but the hose is too stiff but I did kink it which reduced the flow. However there was plenty of time to return to the boat and put it back together and a few minutes later I jumped back in and finished the dive. I guess the important thing here is not to panic, it looks a lot of bubbles but it was not necessary to go to the surface.
Perfect! That's what I thought. I've seen divers go nuts over a bunch of bubbles and noise but, they still had air!!
Good work and a good experience for you - scary but good.
Alec
Amazing video.
Thanks for watching Michael.
Alec
GREAT INFORMATION THANKS!
Thanks for watching John.
Alec
Great video!
Thanks.
Alec
Hi Alec, if you were in the situation with a ruptured hose, wouldnt you be better off to kink the hose to reduce airloss? i never see anyone mention this... surely there is something out there you can clamp on the hose to stop it leaking...
It's not a bad idea Tom and I'm sure there's a way to do it. Something like Vise Grips ought to work - an instant clamp sort of thing.
But, your tank air will last several minutes even with a hose blown out.
Probably best to use those minutes to get to the surface or to your buddy.
The chances of having a useful clamp with you on the dive that the hose blows (1 dive in what, maybe 10,000?) and being able to reach and cut off the air flow is slim, like zero!
Blown hoses that I've seen broke down at the metal ferrule close to the first stage. Hard to reach.
My personal philosophy has always been to get to the surface when something that could be life threatening occurs.
Many divers think that surfacing is an admission of failure. No. Drowning is an admission of failure!
Some divers think that going to the surface quickly is dangerous. No. Drowning is dangerous!
Can't solve it quickly underwater? Look up; short breaths in & out if possible; go up; problem solved.
Good thinking though.
Take care.
Alec
Alec, great video!! The 150 psi is that an industry standard or does that vary from manufacturer to manufacturer???
It varies a great deal and can be anywhere from 120 psi to 160 psi. Neither a low nor a high IP is better. It depends entirely on the design of the regulator.
Generally the IP is between 135 and 150 psi.
Alec
What a cool demonstration!
It was fun, glad you like it.
Alice ur awesome
And Alec too!
@@AlecPeirceScuba_SeaHunter do sherwood first stages bleed and hiss
Hi Alec. Big fan! Have any guesstimates on how many dives you’ve done?
About 10 years ago I was nominated to receive the SSI Platinum Pro Award. In the qualification process they determined from my logs, interviewing colleagues and analyzing certification records that I had made about 6500 dives. My own informal calculation based on my recollections of dives made, both pleasure me training, are close to that.
Thanks for watching Sean.
Alec
Really nice video again ! and I would guess that the low pressure hose having a bigger volume would let you less time to get up to the surface than the high pressure one ? Always a big fan of your vids Alec ! and if I forget before too late I will wish you a very nice holiday season and a Merry Christmas !
Merry Christmas to you too Joel.
Thanks for your support over the years.
Bigger diameter but lower pressure right? So the volume of air may not be higher.
It's a physics question that you'd need to work out. At some point the inside diameter of the hose combined with the pressure will equal whether a large or small diameter.
I think. Alec
That make sense ;) Was saying as I had a free flow on my OW in the open and it scooped half a tank if not more in a really short time hehe ... thanks for the wishes and anytime for the support I love your vids and knowledge !
I had a LOT of suspense in this video.
It's not that big a deal, which is exactly the point.
As with many scuba issues, it's the perceived danger that's most harmful.
NOT knowing what will if something goes wrong can make a diver act imprudently when it does and that can lead to a serious problem.
That's why I like to ask questions and try things that you wouldn't normally see - just to see what happens.
In most cases, it's not that big a deal.
Alec
Alec Peirce Scuba I'm sure we'd all love to see where you simulate more potential equipment failures and their effects!
Hello Alec please could you cover 2 items the Apollo bio-filter and modern full-face masks?
If you read the Apollo Bio Filter sales pitch on their web page you'd swear that this simple device is the answer to all scuba diver's woes!
In fact, it's a simple humidifier. The first such device was made by Farallon in the 70's and was called the SAM - Scuba Air Moisturizer. Essentially it's a cylinder that fits into the first stage between the first stage and your primary reg hose. Removing a small cap allows you to put water (distilled water is recommended) in the cylinder. The water soaks the internal sponge-like material and that water is slowly absorbed by the air as you breath. It moisturizes the air.
So it may reduce dry mouth. That's it.
It will not cure headaches, fatigue, increase your bottom time, filter the air, make equalization easier or improve your erections!
I intend to discuss Full Face masks in a vid soon. I may have to do a Tech Tip AND a Vintage Scuba video for them.
They were quite popular in the 60's and 70's. Many recreational divers used them but today they have become expensive and largely unnecessary scuba devices of greatest value to professional divers, professional divers with lots of money. Their greatest benefit, other than isolating the diver from cold and/or dirty water, is to allow good communication underwater. Personally I value the time underwater with my dear wife Diana - time that is visually enjoyable but without the distraction of her voice.
Alec
Can u show us how to build homemade regulator just like u did. Thanks
Nope!
But I will have the plans to do so available for sale on eBay soon. These are copies of the original plans from Science & Mechanics from the 50's
They will require you to do some searching for war surplus items and to be fairly handy.
I'll also be selling my own homemade scuba units soon - and a lot more too.
My eBay ID is Seahunter.
Alec Peirce Scuba thanks
First off, $3 harbor freight eye protection protectes your $6 eyes. Second off, great video. Should be part of padi training other than fear.
hi Alec...you showed that with the high pressure hose you would have some time before you ran out of air which gives you some time to get to the surface. But the air came out of the regulator hose much faster(no restrictor). So lets say your tank is at 1500psi. How much time do you think a diver would have to get to the surface before running out of air? Thanks. And, when do we get to meet Kevin?!!!
You'll meet Kevin I promise. Keep watching because there won't be any announcement.
The time you have to get to the surface depends on many things, mainly depth. But at 1500 psi, you can easily make an immediate ascent to the surface. Don't stop for pictures!
The most important thing is to keep cool - it's also the hardest thing!
Alec
Hey Alec, first of all, i love your videos! Then a question: During the dive training I learned to point the pressure gauge away from me when opening the bottle because of the possible danger of breaking glass. But the video about cutting the high-pressure hose shows that there is not much volume to apply force. What is true about exploding pressure gauges?
Facing the gauge away from you is a very old idea and based on the earliest SPGs that had glass faces, a take-apart design and no air volume restrictions. That has not been the case since about 1975. You must have had a very old instructor, or a stick-in-the-mud. You know the type - "That's the way I learned so it's good enough for you!".
Today, the gauges are modular (i-piece design), have shatterproof faces and restrictive orifices.
Plus, they have a hard rubber plug in the back of the gauge housing that will blow out in the unlikely case that the high pressure air gets too high inside the case. This plug will fly out like a .22 bullet - right into your eye if the gauge is facing away from you. So the idea of turning the gauge away is NOT good.
I have a video about this. I think it's called Things Your Instructor Taught You That Are Wrong.
The best advice is to simply turn your face away from the gauge as the air pressure is turned on.
Alec
@@AlecPeirceScuba_SeaHunter I just got my OW last year, so a newbie on diving but very interested. Greetings from the Netherlands!
@@AlecPeirceScuba_SeaHunter I heard a young instructor (who wasn't even alive in the 70s and may not have been alive in the 80s either) say this within the past couple years. Also, a lot of tech diving gauges have glass faces even today. I agree about the advice to turn your face away from the gauge though.
next tech tip: what happens if my tank ruptures? haha
You'll never know! LOL.
My dad used to tell me to not be afraid of thunder. He said, "If you hear the thunder, you're ok. It's when you don't hear the thunder that it hurts."
If you hear a tank rupture, you're probably OK. It's when you don't hear the tank rupture that you get hurt!
What do you want - for me to blow up a tank on You Tube? That ought to raise my views!!
Take care PF.
BTW, that looks like a Suzuki on your home page but what are you riding in your profile image?
I've been riding since 1965 and still have 4 bikes (I'm 70 years old!).
Alec
thats my old yammie on my homepage and the profile pic is my current bike a street triple r. I'd like to see you show off your bikes in a video sometime, perhaps on the ranch channel?
and yes I would very much like to see you blow up a tank for youtube lol
I thought it would be like in jaws
In that movie they shot a scuba tank in the sharks mouth, to kill it with a huge explosion (totally not true). Now you saw what a real hose cut looks like. Lots of time to ascend safely.
A
I had 2 lp and 1 hp blown. But usually they fail near the metal fitting.
Yep! That's why my Tech Tip on regulator care emphasized checking those ends.
Alec
What?! No drum roll? 🦈
Nope, just a doggie roll.
Irwin tools just aren't what they used to be..😂
NOTHING is what it used to be Rich. One has to be vigilant to find quality these days.
Alec
so basically only dive computer or transmitter goes to the HP port. Octopus, low-pressure BCD hose, all goes to LP port.
Right! The HP port shows tank pressure.
Alec
Alex so you visually check your hoses for signs of wear and tear etc and everything looks to be in good working order. What could cause a hose to pop nothing concerned you during the visual check? Thanks
I check my hoses regularly - not before every dive but maybe monthly.
Generally, hoses are very durable. There is no reason for them to fail in normal use.
Many years ago, every DACOR regulator we sold had a hose that blew wide open when the air was turned on. It was a defect in the manufacture of those hoses. Scuba companies do not make their own hoses but buy them from another company. Needless to say, DACOR stopped buying them.
Take care.
Alec
Can a typical 1st stage reg maintain anything like 10bar/150 psi in the octopus with a fully cut hose on the primary 2nd? I suspect it can't!
A free flowing 2nd stage is actually relatively limited air flow because the metering orifice in the 2nd stage is significantly smaller area/diameter than the LP hose ID and this scenario is a test that the regulator manufacturers do (and have to do for certification/type approval). But with a completely cut LP hose, worst case next to the 1st stage is going to prove a problem, because the regulator piston/diaphram will be fully retracted off the 1st stage metering seat, and yet there will be hardly any restriction down stream of that seat due to the cut hose.
Of course, in reality a completely cut hose is just not going to happen, outside of a James bond movie underwater fight scene of course.........
Good question. I've not explored that and may do so in a future Tech Tip.
However, I do know that if a 2nd stage, primary or Safe Second, is held open as in a complete Free Flow position, the IP drops very low, so low that it would not supply sufficient air to the other 2nd stage to allow you to breathe.
Fortunately, as you say, that's a very unlikely occurrence.
Alec
Hey, couple weeks ago my istructor`s regulator got separated from the hose (yeah i know...) the hose started whipping around bad, hit him on the mouth, he had to submerge so we would have a chance to turn air off, hose just kept whipping around
Odd but possible. The separation firstly is very unusual and the hose whipping around is strange. The heavy metal fitting on the end usually keeps 'whipping' to a minimum.
However, like a garden hose, some will and some won't.
I hope everyone is OK.
Alec
@@AlecPeirceScuba_SeaHunter yeah, when he submerged we were able to turn the air off. And you are right, he still had plenty of air to finish class :)
I would like to know how many minutes it would take to drain a full tank with a Lp failure.
Lots of factors will affect that but roughly, 4-5 minutes.
Alec
Depends on depth for a start as one factor.
@@greatwhitesharky3261 I don't think depth has any bearing at all! The pressure in the tank may have an influence. You will be losing air at an astonishing rate whatever depth you are!
@@Graggs Yes, but at the same time you are still breathing and using air, so the greater the depth the harder you breath. If you breath air at depth of course the air will not last so long compared to being shallow.
Absolutely correct@@greatwhitesharky3261
Hi I’m just starting to get into scuba diving and I need to get my wetsuit I live in New Zealand (so cold water) and I have come down to 2 wetsuits one is a 1 pice wetsuit and the other is a 2 pice both are 7mm which one is the smarter option
The one that you are more comfortable with. As both are wetsuits both are equal here (drysuits are a pain to put in, I really hate the neck seal).
If both cost more or less the same, and both fit you nice.... well I cant choose for you. The best thing is to try both.
thank you for the information
Sorry for the delay. I actually made a long reply to your question but then I lost it during a computer glitch. I was so frustrated that I left it.
Here's my thoughts:
1. the 2 piece wet suit was the standard for many, many years. It was a pair of pants that came up to your chest only (called Hi-Pants) and a jacket that had a Beavertail - a strap that went down underneath your crotch to hold the jacket down. That was replaced by the Farmer John style pants with shoulders and the Step-In jacket. It was great for warmth although quite restrictive with all that material. It was really a 14mm suit from the neck to the crotch so made it very stiff to wear - and buoyant too.
2. The 1 piece suit is simply that - 1 piece that you climb into and zip up the front or, more commonly now, the back.
3. The Almost-Dry or semi-dry (I see that mentioned in one of the replies) is the same suit but with rubber seals at the neck, wrist
and ankles. They are supposed to keep water from flowing in and out of the suit.
As an historical note, the semi-dry suit was first designed by the late Frank White Sr. of White's Diving in Vancouver. He designed the Cross-Chest zip, zipper flaps, attached hood and a dozen other great ideas to make divers happier underwater.
So, I suggest the 1 piece suit. It has almost replaced the 2 piece suit in most environments. It is cheaper, easier to doff and don, less restrictive, more flexible, less buoyant and just as warm. The 1 piece suit has openings only at the neck, wrist and ankles while the 2 piece has that large overlap at the waist. Some divers will say that 14mm (double thickness) is warmer than 7mm. Nope. It's not the thickness of the neoprene that keeps you warm. It's the trapping of the thin layer of water under the wetsuit. 7mm is the thickest you need even for very cold water. Here in Canada we dive all winter long through a hole we cut in the ice. I venture to say that it's colder than your water - 0 degrees (32 for our American friends) is about as cold as you can get!
As for the semi-dry, most suits now are so flexible that they seal really well at the neck, wrists and ankles anyway. Actually, a lot of wetsuits now come with a rubber seal on the very edge of the wrists and ankles and your hood seals the neck and face. Most of the features that made the semi-dry great are now incorporated into the regular wetsuit so there's really no need to pay a lot more for a semi-dry.
The critical thing is fit. Spend some time at your LDS and try on several suits, styles and sizes. You need one that's flexible and stretchy but a close fit all over your body. Not too tight! That will stop blood circulation to the extremities and you'll get cold. Check for gaps down the back (cold water down the back is NOT nice). Most back zips will have a thick pad down the zipper to help stop that. Check under the armpits and the crotch for big gaps. Ladies check the chest.
If the suit is the newer nice and flexible neoprene, you shouldn't need extra zips at the wrist or ankles.
The same principle applies to your hood, boots and gloves - snug but not too tight.
I hope some of this info helps you make a decision.
Thanks for watching.
Alec
Has anyone tried to krimp a mid pressure hose in that type of situation? That's something I've always wanted to try.
I'll have to do that on a video. I don't think it's possible but let's try.
Alec
@@AlecPeirceScuba_SeaHunter I'm visualizing a run-away free flowing second stage. Our hero whips out his handy vice grips and saves the day. Tanks for entertaining the thought.
Looking in the internet world, there are some people that claim that a low pressure hose failure would empty your tank in about a minute and a half. (Due to the high volume of air flow). While a high pressure hose failure would take well over 10 minutes. (Low volume flow). Does that sound right? Has an actual test been conducted?
Yes. I have done such tests and I can assure you that any diver with half a brain could easily reach the surface if a hose blew.
What many 'experts' forget is that the LP hose, the primary regulator hose, gets its air from the 1st stage. It doesn't just blast out of the tank. It goes through a couple of restrictions and only leaves at a pressure of 150psi regardless of the hose diameter.
Relax. Check your hoses.
Alec
Hi @@AlecPeirceScuba_SeaHunter
I've only just found your videos and I've already watched a load of them. I'm really enjoying your style and content, even though I know a load of this stuff, it's great hearing it come from you!
BUT I have to take issue here!
A low pressure hose failure is pretty much as bad as it gets and @Aaron is about right, a 12 litre tank empties very quickly. I believe it varies depending on the tank pressure, but an average is around 24 litres/sec. So, for a 12 litre tank pumped to 200 bar that's 100 seconds or just over 1½ minutes!
With a safe ascent rate of 18m (60ft) a minute, you can see how serious this is!!
If you are diving at turn pressure (around 110 bar) and at depth (say 30m /100') when you have your failure, you will not have time to relax! You will have exhausted your tank in less than a minute, your safe ascent will take you about 100 seconds (assuming you have no overhead obstructions - needless to say, you will not be doing a safety stop or deco (unless you have other tanks/stages or a buddy that is right with you)
Not so sure about this video. With the low pressure hose were you not restricting the flow with the tank valve? Also if this happens at 90ft / 30m how long would a half empty scuba tank last compared to such a failure on the surface?
There's a great video showing how long it takes for a free-flowing regulator, a faulty LP hose and a HP hose to empty at 1 ATM (surface), 3 ATM & 5 ATM.
vimeo.com/151452141
I wasn't restricting the flow. Realize that there is a natural restriction from a the first stage. It will only deliver air at 150psi above ambient and the flow rate is slow and constant regardless of pressure or depth. Air does not pour out at a high rate. That was the point of the video.
Since the IP (intermediate pressure from the first stage) is always 150psi above ambient, there will be no change in the flow at any depth. However, at any depth your rate of consumption changes. Technically the air will come out of the tank at the same rate regardless of depth so the flow from the torn hose will continue just as long. But you consume much more air as depth increases so it will not last as long.
I know this sounds odd but think about it for a while.
Thanks for watching.
Alec
Geoff Infield
Hi. Try this link instead.
th-cam.com/video/Dnwz7r-pHqg/w-d-xo.html
What about diving helmets?
There's not much room for helmets in recreational diving Gio.
Some of my vintage diver friends are crazy about old helmets and collect them.
A short while ago I sold my own Mark V helmet, suit and all the accessories that I'd owned, and used, since 1975.
I used the money to buy a brand new Indian Vintage motorcycle.
When I'm on the bike I don't even think about it but when I'm not, I miss my helmet.
It was a genuine 1944 version that I got from Seneca College Commercial Diver School after my course.
It was used by the US Navy, then sold to the Canadian Navy before Seneca bought a bunch of them for their new course back in the 60's. If it could only talk - what stories!
Thanks for watching.
Alec
So the rubber sheathing of my lpi hose is torn, but the nylon looks good. Is it time to replace it, or can I keep using it for a while? (its 12 years old if that makes a difference)
Several factors determine hose replacement. Age (12 years is long), and if the rubber cover is torn, yes replace it with a flex hose (you will love them). It's not work trying to avoid a replacement as todays flex are super light, flexible and colourful too.
@@AlecPeirceScuba_SeaHunter Should I go ahead and replace all of them since they are all about the same age?
@@mgmgeorge3 I would, because the money spent is worth the safety, and saved frustration in the future
No HP in my life
Quad air masterrace
Lol wat ^
How fast will tank empty with a blown O ring at talk valve?
good question - FAST. I had my regulator main O-ring blow on me (high pressure unrestricted) just steps from the water at the beach last week in Maui, after being on for a couple minutes and it was loud (Aeris AT600 first stage) and scary as I had just done 2 deep dives that morning (60-80ft) and was just playing around taking the kid to try in shallow water - makes me wonder what would have happened if it had been earlier that day while underwater... could have been fatal if I wasn't diving with others. Yike!
Thats why I personally keep a bailout pony - they won't stop decompression illness but I won't drown.
Fast. At the valve face the air is unrestricted (see my earlier reply to IM35461) and will pour out of the tank rapidly. Normally the valve is fully open. It will still take 3 to 4 minutes to empty. Keep your cool and make a safe ascent. Air ought to still be available through the reg. Unless you're down several hundred feet, you'll be ok.
Do Milflex hose need hose protector?
I talked about this at length in a video a while ago. I think the topic was flex hoses.
The short answer is that I don't think hose protectors are important on flex hoses.
Hose protectors are valuable on the normal stiff rubber hoses but they can cause corrosion of the end fittings if not pulled back and rinsed. Better off without them if possible.
Alec
Alec Peirce Scuba, thank you for the info.. my wife and I love your channel.. it bring back so much memories. Another question, I live in Boston and the diveshop around where I live can not service my 12 to 14 years old regulators. They just want to sell new regulators. So I am driving up to Scuba 2000 to have my regulators service, and we need 2 new BCD. Like the one you have for traveling. We wish we can meet you in April 2018... and happy holiday.
what could be posible things can happen diving alone one buddy on top of water on boat
Suppose the diver in the water finds a gold coin while his buddy is topside? That's a silly way to lose a good buddy!
There are lots of things that can happen while diving alone. The list is endless but that's also the case when diving together.
If diving alone you simply have to avoid any situation where you can get into trouble that you can't correct on your own - you're on your own!
Alec
If I find gold coins I'd ask my buddy to surface immediately so that he doesn't see it, mark the location and then dive again(alone) with extra equipment.
Well if that happens to you primary regulator hose you just switch to your octopus and make your way to the top because you're going to be dumping air like a madman worst case scenario you could just breathe using the bubbles like you would with a free-flowing stuck regulator
If you are calm and cool that's certainly what to do.
Thanks Joseph.
Alec
See my comment above!
You do NOT have that much time! You will also be in a panic!
One important question can scuba diversity can be blackout .if yes what's cause reasons n
Sorry but I'm not sure sure what you are asking.
Try again.
Alec
What is your question? I don't think you proofread it before posting. Is your question, "Can scuba cause a blackout?" You can blackout if you run out of air but that is true on land as well. As he said in the video, you would have time to surface in the unlikely event of a hose malfunction.
The bad guys on Sea Hunt could cut thru those big hoses without much problem.
Yes it seemed that way.
The big hoses on a double hose reg are much lighter rubber, lighter even than a bicycle inner tube. They were easy to cut.
And in the TV shows they were pre-cut to be sure they broke at the right time and the right place.
Alec wasn't using a 12" dive knife if he had been he would have been through that hose like greased lightning through warm butter.
Now I'm not worried if a shark bites my hose... but what if the shark bites my tank?
He's going to have a toothache!
The Bull Shark has the strongest bite and it's been measured at less than 500 pounds of force.
500 pounds on a scuba tank will not even scratch the surface, well, maybe scratch it, but realize the tank is about 1" thick and is supported on the inside by a force of 3000 pounds pushing out on every square inch (when full).
Interesting that you are thinking about getting bit by a shark and worried about your tank!!!
Alec
aren't you damaging the bottle by doing this?
Not that I can see. I'm not sure how a burst/torn/cut hose would affect the tank.
Alec
Put it in reverse terry
Huh??
Alec