Relitave Pressure

So just becasue one has taken a openwater scuba certification course does not mean that one paid attention during class or actually learned anything.

So picture this...a gentleman (if you can call him that) walks into the shop. He kind of looks like the comedian Larry the cable guy...stocky, plaid shirt with the arms cut off, blue jeans, engineer boots and a CAT tractors baseball cap. He says Howdy in a decesivly redneck accent. Don't get me wrong I'm redneck at heart but this boy was oozing it all over.

He says I seem to have the problem when I'm cleaning my swimming pool. I'm under the water breathing and I am getting very very dizzy. Of course we are all assuming he is using Scuba gear as he is breathing under the water, and he has mindlessly ventured into of all places a scuba shop. We are all a bit worried that he may have gotten a bad tank of air and begin to question him.

Well now boy and girls this fella takes off his cap with one hand, and scratches his balding plate with the other, and says well I'm not using a tank...I have a 30 foot garden hose that I take down and breath out of it and my wife is on the other end blowing fresh breaths into it.

Okay for any one scuba certified and who paid attention to relitive pressure as well as the weight of air. First we know that in order for him to actually get fresh air through this garden hose it needs to funnel upwards getting larger as it gets toward the surface as this fella even in his pool is at about a .5ATA so he is breathing under pressure. The top of this hose will have to be about 2 to 3 feet in diameter for him to actually get any fresh air.
Trying to keep straight faces it is explained to this guy that first as he takes a breath he gets a bit of air from the hose..then as he exhales he is breathing (what do we remember from 8th grade science class boys and girls) carbon dioxide into the hose which probably travels about 2 feet up the 30foot length of hose, then he inhales this carbon dioxide right back into his system. In the mean time his wife is on the surface blowing (wonder of wonders) more carbon dioxide into the hose, which luckly due to the length of the hose probably isn't reaching him anyway. He's got enough problems of his own at the bottom of his pool.

After explaining all of this to the man, he looks a bit confussed, his eyes are most definatly glazed over trying to think it all through and says in that loving very redneck accent..Well I guess I could cut the hose down to about 15 feet. Many of us at this point had to walk to the back room as we were having relitive pressure issues of our own turning multiple shades of purple trying not to laugh in this poor innocents face.

The shop instructor and owner then just looks at him and says well sir you could do that but the shorter the hose the dizzier you get. The fella looks up and says really...so should I get a longer hose again (insane laughter is emmitng from the back rooms at this point) The instructor says well you could certinaly do that but I think it is likely that you will pass out and drown at the bottom of your pool.

Larry the cable guy then asks well how am I supose to get my pool clean. At which point he was told to go home, drain all the water, take a wire brush at the stroke of midnight and clean one inch at a time.

My friends. I think the police were called to the residence of this man as he was draining his pool...
So much for the pool cleaning.
Moral of the story...Please don't use a 30 foot garden hose to try to breath out of in order to clean your swimming pool...

comments always welcome..if you find this amuzing please pass it along to others.