Question about Chlorine

[gamecat]

I am having an ongoing argument with my friend at the moment about chlorine in swimming pools. The two arguments are.

 

1. That chlorine itself causes the smell and irritation to the eyes and that urine does not contribute to/or play a mjor part in the smell and irritation.

(his argument)

 

2.That chlorine is odorless and does not create irritation or 'bleach' smell in itself. It is urine combines with chlorine that creates choloromines and it is these choloromines that causes sore eyes and the odor.

 

We both agree ph balance can also effect peoples eyes and skin.

 

Who is correct as eveidence on the internet seems to contradict.

 

Many Thanks

 

GC

[CharonY]

It is indeed assumed that chloramines are mainly responsible for the irritation and smell in swimming pools.

However, it is wrong to assume that chlorine is odourless. You just need a bright student performing electrophoresis with HCl-containing buffer...

Chlorine gas has a very strong odour, however the amount used in pools is rather low.

[insane_alien]

the smell is chlorine. albeit very very dilute otherwise you'd start coughing up various organs and various other vitals. Urine doesn't cause the smell since even a freshly cycled(emptied and then refilled, usually to perform some major maintanence) pool will have the same smell.

[woelen]

In a pool the typical smell of chlorine is due to a mix of elemental chlorine, hypochlorous acid (these two are desired and are disinfecting), and chloramine, NH2Cl.

 

The irritation, however, mainly is caused by the chloramine. The latter compound is formed from urea (and derived from that, ammonia) and hypochlorites in the pool-water. The chloramine also is not useful anymore as disinfecting agent. It only irritates.

 

In a pool there are two kinds of chlorine: free chlorine and total chlorine. Free chlorine is the Cl2 (and HOCl) in the pool and total chlorine is free chlorine plus the chlorine, bound in NH2Cl.

 

If a pool has a very strong and irritating "chlorine" odour, then surprisingly, a shock-treatment with a lot of hypochlorite makes the pool less irritating and less odourous. With the excess hypochlorite, the chloramine is destroyed (giving mainly N2, water and chlorine) and the irritating stuff is gone.

[jdurg]

Correct. Pools are kind of like a very, very dilute bleach solution. There are hypochlorite ions and hypochlorus acid inside the pool water. HOCl and OCl- will create small amounts of chorine gas which helps out with the disinfecting. The human nose is able to smell chlorine in amazingly low quantities so the very miniscule amount tha does escape the water is readily noticed by humans.

 

The lower the pH, the more chlorine gas is produced. At a higher pH, most of the HOCl/OCl- remains as such in solution and the odor isn't as noticeable. If you lower the pH, the equillibrium shifts towards the production of Cl2. So while the pool will wind up being "cleaned" more, the smell and effects of the chlorine will be noticed more.

 

The argument you are using (#2) does not hold true as freshly made pools where the water has just been added and the chlorine tabs added will smell like chlorine. In addition, the chlorine tablets that are used smell like chlorine and there's definitely no urine in there.

[jdurg]

In a pool the typical smell of chlorine is due to a mix of elemental chlorine' date=' hypochlorous acid (these two are desired and are disinfecting), and chloramine, NH2Cl.

 

The irritation, however, mainly is caused by the chloramine. The latter compound is formed from urea (and derived from that, ammonia) and hypochlorites in the pool-water. The chloramine also is not useful anymore as disinfecting agent. It only irritates.

 

In a pool there are two kinds of chlorine: free chlorine and total chlorine. Free chlorine is the Cl2 (and HOCl) in the pool and total chlorine is free chlorine plus the chlorine, bound in NH2Cl.

 

If a pool has a very strong and irritating "chlorine" odour, then surprisingly, a shock-treatment with a lot of hypochlorite makes the pool less irritating and less odourous. With the excess hypochlorite, the chloramine is destroyed (giving mainly N2, water and chlorine) and the irritating stuff is gone.[/quote']

 

Heh. We kind of posted at the same time. In addition, raising the pH of the pool with various pH Plus products will lower the amount of chlorine present in there and lower the "odor" that is found.

[gamecat]

So it seems it is somewhere in between, but essentially chlorine is not odorless but the main contributing factor to eye soreness and airway irritation would be chloramines.

 

Does this sound right?

 

thanks

[YT2095]

that about sums it up, yes .

 

you`re Both right and also wrong on various points, shake hands and be gratefull you didn`t put money on it

[gamecat]

Money is worth less than pride in our case. LOL

 

Thanks for your answers, definately more complex than I had assumed but very interesting.

 

Thanks

 

GC