Question for Scuba Diving Fireman

[mainmanpaul]

Just wondering why firemaen wear there air tanks with the valve on bottom which is obviously oppisite to how you wear a tank in scuba. I was guessing it is either to protect the valve or it's a "That's the way we have always done it and nobody sees any reason to change now" sort of thing.

 

[Xanthro]

Some Scuba divers where their tanks valve down, though this is usually a supplemental tank, such as a pony tied to the main tank.

Firefighters are inside buildings and are engaged in very tight situations, it is quite possible for the valve to hit something and break if it is point up. Though it is harder to reach pointed down, they are with a trained team, and the hose routing usually precludes their mask from being ripped off.

For Scuba, you need to get your regulator back if it falls off, and you need to be able to reach your valve in case something goes wrong. Plus, unless you are very advanced, you aren't going into really tight spaces, and then you will likely be doing side mount.

Xanthro

 

[Staredge]

You'd also have issues with the back of the helmet hitting the valve. Also, the regulator has two knobs: one for normal breathing and one emergency bypass. Unlike diving, firefighters can't afford to have anything come into the facemask from outside. A little water in your regulator canbe blown out. Smoke ain't no fun!!!!

 

[firemedic296]

there are many reasons for the tank position the way it is. some have been stated. also to aid during entanglements. It is easier to remove stuff, like electric wiring and hvac duct wire, from around the bottom of the tank rather than the valve, any firefighter can probably give many reasons from their own experience. you are right, firefighters resort back to tradition for the most part, but there there really isn't any reason to change.

edit: change the tank position that is.
there is alway room for good change in the fire service, but like anything else the decision to change is tough, but not as difficult as trying to decide what or where to eat. haha

 

[PaulChristenson]

Just wondering why firemaen wear there air tanks with the valve on bottom which is obviously oppisite to how you wear a tank in scuba. I was guessing it is either to protect the valve or it's a "That's the way we have always done it and nobody sees any reason to change now" sort of thing.

100 YEARS of TRADITION unaffected by PROGRESS

Actually the major reason has been stated...To protect the valve assembly...
During an interior operation, when you start to rip down the ceiling to look for fire extension...sometimes more comes down than planned...better that stuff lands on the bottom of the bottle than the valve and hoses

The other major reason its upside down is that it is safer to reach around the body with your arm next to the body to turn on the air than to raise your arm over your shoulder...less area of your bunker gear exposed...


Paul in VT
FF/EMT, Hazmat/Rescue Tech

 

[diverdescent]

Funny, I was just having a conversation similar to this in my LDS just yesterday. I am a former FF/EMT. I have several questions as to some things that might transfer to diving.

For instance, when are they going to come out with a high pressure composite bottle for scuba use? We've been using the carbon fiber ones for years, (at the department) and, at close to half the weight. I'm sure there is reasons why they are not used but with technology today, shouldn't we be able to overcome the problems?

Next, every other scba had a buddy breather hose that plugged into a port just above our pressure gage, so if we ran low, we could plug this into our buddies and it would equalize the pressure in the two bottles, giving you both the same amount of air. Couldn't this also be applied to scuba? I think it could. You could then unplug the hose and make a safe ascent.

Like I said, I'm sure there are reasons that these couldn't be applied to scuba, but I'm sure they could be overcome.

After all, wouldn't a 4500psi bottle smaller and half the weight of an 80, but lasting the same amount of time be great?

DD

 

[Wildcard]

SCUBA bottles only have a weight issue above water so it dosen't make a lot of sense to spend the coin on the carbon fiber bottles. Id also think that they would be very prone to corrosion if the fiber layer was damaged.
When you plug into your buddies SCBA it dosent equalise the tanks, you are breathing off the same tank, just like an AAS.

 

[Bob3]

Interspiro has been making & selling fiber wrapped bottles for scuba use & they have been around for years, mostly in Europe. Theirs has something like a 40 year life span.
A few years back Luxfer come out with one, it's expensive as heck & needs to be thrown away after a number of years, 10 if I'm recalling correctly.
I have some 4400psi steel bottles & have a HECK of a time getting a decent fill.

 

[Wildcard]

Carbon fiber SCBA tanks have a 15 year life span, period, no retesting or anything. Don't know about the SCUBA tanks life span.

 

[Jim Baldwin]

There is already a company that makes fiberglass/carbon fiber wrapped scuba tanks. I think that this will just be a speciality item due to the cost and also to the limited life cycle.

I saw one in a magazine recently I believe it was XS Scuba but I might be wrong about the name. The problem I see is that all these tanks are ultra high pressure requiring some 4400 psi or better to obtain a full fill.

I dive PST HP 100's and 120's and have a hard time getting a 4000 psi fill so that my tanks will actually have 3500 psi when they are cool. Only one out of three shops in my area can actually do this and the owner wants to be there when he runs his compressor up this high.

The plug-in hose for your SCBA rigs is exactly the same thinking as the alternate air source for scuba. With a full face mask in a contaminated environment the plug in hose alllows you to get more air without having to remove any of your head protection.

Donating a regulator takes only a couple of seconds. If the receiver panics and makes a dash for the surface they are not attached to a hose of any kind as the reg will simply pull out of the receiver's mouth.

Jim