Snuba air line filters?

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I'm putting together a dedicated SNUBA Hookah hose rig that will use a tank on the surface for air. If I'm using a tank, do I need a filter inline in the air hose? Thanks.
No absolutely not. No inline filter. But it does depend on what you intend smoking down your Hookah hose. Although the water temperature surrounding the hose rig can be used to your advantage in cooling the contents however sadly the type of particulate filter fitted inline in the hose as you suggest will by its very nature fail.

Further filters of this type (inline) will only collect the particulate and over time this at best reduces the flow up to the point of clogging.

The first of two important safety components you will need however is a non return valve fitted at the end of the hose nearest to where you are in the column of water. This acts as protection in the event the surface cylinder hose from the reducing regulator bursts at the surface creating a vacuum down the hookah hose. Choose the type of hose carefully.

Remember a hose at the surface gets very hot soft and pliable from the sun while the hose in the water is being cooled by the sea temperature and the hose can be hardened and brittle over time especially the cheap crap PVC imported junk hoses sold by the rinky dink scuba dive web sites. Conversely the type and method of crimping the hose to the 7/16 UNF 1st stage regulator fitting also needs careful consideration be it swaged pallet swaged or crimped.

The pressure differential of surface ambient pressure to depth pressure will act as a massive vacuum suction to the diver if at depth hose line pressure is lost by a burst hose at the surface. This will result in a rapid suction action reversing the gas flow from the divers depth end back up to the surface while the water pressure crushes the hose. Now in principle when this happens and you don't have the correct type of non return valve fitted at the divers end the 2nd stage box bottom exhaust valve will at some point invert and get sucked in or the front diaphragm inverts and is sucked inside However its the weaker human lung function capability to protect itself from even a small pressure differential loss hence why you never see a 3 foot long snorkel that is the concern. At this point not only have you lost your last breath but you have damaged lung function and together with the sudden onslaught of a vacuum you have zero time react. Consider your hose type brand material and internal diameter very carefully and the fittings type and method of attachment. Take greater care on the type and spring pressure of the non return valve.

Loss of lung function at depth is interesting. We all know about the nemesis condition of a spontaneous Pneumothorax leading to an arterial gas embolism and its chamber treatment protocol although on the couple of times I've seen one they never needed a chamber treatment. I'm just not sure what treatment table you would use for a diver presenting with a serious opposite vacuum condition does his lungs dangle out his mouth if so maybe a local embalmers with a bucket to spare would be helpful I guess.
 
No absolutely not. No inline filter. But it does depend on what you intend smoking down your Hookah hose. Although the water temperature surrounding the hose rig can be used to your advantage in cooling the contents however sadly the type of particulate filter fitted inline in the hose as you suggest will by its very nature fail.
Further filters of this type (inline) will only collect the particulate and over time this at best reduces the flow up to the point of clogging.
UUhhmm..Isn't that the whole point of the filter? To trap debris and plug up? If a filter never plugs up, it's not filtering anything out. Just carry spare filters. They're cheap.

However, the hose non return valve is interesting. I will check into that. Thank you for the heads up.
 
UUhhmm..Isn't that the whole point of the filter? To trap debris and plug up? If a filter never plugs up, it's not filtering anything out. Just carry spare filters. They're cheap.

However, the hose non return valve is interesting. I will check into that. Thank you for the heads up.
Clearly the original statement No absolutely not. No inline filter. wasn't clear enough.

Now you need to elaborate on the type of filter you intend using its size diameter and bed length the mean pore size and pore diameter also the filter type, pleated, cone, or element type, Also if sintered, or dutch mesh are your preferred type and in what material you require. Also any Dp considerations together with your filters placement at the surface or at divers depth then maybe we could elaborate more on some of the considerations needed to make an informed choice.

We could also have discussed a suitable non return valve for your underwater adventure especially the type of valve and the non return spring rates. Alternatively as you say just carry spares they are cheap.
 
UUhhmm..Isn't that the whole point of the filter? To trap debris and plug up? If a filter never plugs up, it's not filtering anything out. Just carry spare filters. They're cheap.

However, the hose non return valve is interesting. I will check into that. Thank you for the heads up.
There's no filter in the low pressure side of a scuba regulator, why would you add one to your snuba rig just because the hose is 20m long?
 
There's no filter in the low pressure side of a scuba regulator, why would you add one to your snuba rig just because the hose is 20m long?
Two reasons actually. First, my rig will be supplied by a tank but I may want to use a compressor sometime in the future. Yeah I know. The compressor will have it's own filter. But, I'd just as soon be really really sure that I'm not breathing microscopic metal filings from the air pump. Second, the hose is 25 times as long and that gives it that much more space for an internal flake to peel off.

Another reason that's not to valid but legit just the same, is because every rig that I've looked at in catalogs, web sites, etc, shows the hose and regulator with a filter in between.

Like I said earlier: I have not Hookah dove in over fifty years and have never SNUBA dove. This is all new to me. I've researched it and listened to the opinions of others and will make decisions based on that.

Honestly, I don't think the filter will cause any problems and may prevent one or two. It's a new breathing air quality hose and canned air so it's all pretty clean to start with. I'll carry spare filters.
 
Clearly the original statement No absolutely not. No inline filter. wasn't clear enough.

Now you need to elaborate on the type of filter you intend using its size diameter and bed length the mean pore size and pore diameter also the filter type, pleated, cone, or element type, Also if sintered, or dutch mesh are your preferred type and in what material you require. Also any Dp considerations together with your filters placement at the surface or at divers depth then maybe we could elaborate more on some of the considerations needed to make an informed choice.

We could also have discussed a suitable non return valve for your underwater adventure especially the type of valve and the non return spring rates. Alternatively as you say just carry spares they are cheap.
Yeah, it was pretty clear but I'm choosing to ignore it. The cartridge is a 5 micron poly fiber carbon type and it will be mounted at the bottom end of the air hose so it can filter all of the air just before I breath it. What good would it do mounted on the tank? Regarding the non return valve: I can't find any information on their requirement for shallow water SNUBA/Hookah diving. Lots of stuff for deep water yes but nothing for less than ten meters. I think I'll pass on that item for the time being. If I loose my primary air, I'll just switch over to my bail out bottle or most likely, just surface.
 
Yeah, it was pretty clear but I'm choosing to ignore it. The cartridge is a 5 micron poly fiber carbon type and it will be mounted at the bottom end of the air hose so it can filter all of the air just before I breath it. What good would it do mounted on the tank? Regarding the non return valve: I can't find any information on their requirement for shallow water SNUBA/Hookah diving. Lots of stuff for deep water yes but nothing for less than ten meters. I think I'll pass on that item for the time being. If I loose my primary air, I'll just switch over to my bail out bottle or most likely, just surface.
Why bother asking?
 
Why bother asking?
Because I wanted information, not a "because I said so". Statements like "Clearly the original statement No absolutely not. No inline filter. wasn't clear enough." are not conducive to a reasonable conversation. Don't tell me no. Tell me why not. And don't get upset when I ignore your advice.
 
Second, the hose is 25 times as long and that gives it that much more space for an internal flake to peel off.
You have this really weird paranoia about the nylon lining to the hose breaking down. Are you getting some super cheap non-scuba or a now recalled milflex hose?
 
Because I wanted information, not a "because I said so". Statements like "Clearly the original statement No absolutely not. No inline filter. wasn't clear enough." are not conducive to a reasonable conversation.

That's a bit unfair.
You forget that I went on to explain about a dozen considerations you need to make in order to make an informed choice decision and in order to do this went on further to each of the decisions needed.

1 The filter type
2. Its size
3. Its diameter
4. The filter component bed length
This will give you a rough idea of the Cv capacity factor Then:
5. Its type to establish Mean or average pore size
6. Its pore diameter to establish pressure drop

7. Flow using Dp to calculate flow capacity directly proportional to the square root of Dp
This may have developed into a conversation regarding lung compliance chest wall compliance and airway resistance due to your age 50+ (you stated your 50 years diving) with any morbid obesity considerations as my work used to incorporate converting the Oxford Penlon medical ventilators for medical Hyperbaric use as we manufacture diving and small hyperbaric chambers.

8. Then the filter type
9. Pleated: Bigger surface area
10. Cone: Better Dp pressure resistance across the filter wall
11. Element Type
12. Sintered: A porous metal matrix compacted into a metal shell blank end shell or tube
13. Dutch Mesh: A porous fine wire mesh in opposing directions to catch particulate dependent on mesh size.
14. Material with moisture and flood tolerance considerations

I then went on to say:

"Then maybe we could elaborate more on some of the considerations needed to make an informed choice". We could also have discussed a suitable non return valve for your underwater adventure especially the type of valve and the non return spring rates.

I'm sorry but If this above wasn't as you put it "conducive to a reasonable conversation".
I don't know how to help you further. Carry on with your internet search and catalogue knowledge from those importing cheap junk from China and take your information and advise off those rinky dink scuba Hooka clowns selling you this stuff.

Don't tell me no. Tell me why not. And don't get upset when I ignore your advice.
I didn't. I did, I won't
 

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