Water Chemistry in Pools
It may sound odd, referring to your pool water as some kind of science experiment, but this is not far from the case. Your pool’s water composition in terms of pH balance and chlorine ratio to name a few, are absolutely critical in keeping you and your family swimming in healthy, germ free water. Clean, clear, uncontaminated water is predominantly a function of properly maintained equipment (such as pumps and filters) and use of the correct swimming pool chemicals. Knowing what type of chemicals to use, when to use them and in what quantities is beyond the scope of this short narrative (†), but what follows will give you a very generalized understanding of what is important.
General Water Safety Guidelines
Germs cannot be seen, however there are some very simple actions you can take to help identify a healthy pool and a potentially risky one.
Look for water that is clean, clear and unclouded. Standing at the side of the pool, you should be able to clearly see the drain cover in the deep end of the pool. Generally, the water level should be at the middle of the tile or just above to insure proper skimming and filtration
The tiles of the pool should be smooth and clean, discoloration or slippery tiles can be caused by algae or poor water chemistry. Running your hand through the pools water should leave no residue or otherwise remarkable feeling.
The pool in question should not have a strong chemical odor of any kind. Chlorine, whether it is naturally produced through a salt system, or added as a straight chemical agent, keeps pools germ free and healthy. A chemical imbalance may be present should swimmers experience skin, eye or respiratory irritation.
Lastly, listen for the pools cleaning equipment. Properly operating pumps help make sure that clean, chlorinated water reaches all parts of the pool, while filters remove very small debris which may be circulating in the pools swimming water.
Chlorine and Recreational Water Illnesses (RWI)
Chlorine in swimming pools kills the germs that may make people sick, but it takes time. Chlorine in properly disinfected pools kills most germs that cause RWIs within minutes. However, it takes longer to kill some germs such as Cryptosporidium that can survive for days in even a properly disinfected pool. Also, many things can reduce chlorine levels in pool water. Some examples are sunlight, dirt, debris, and material from swimmer’s bodies. Healthy swimming behaviors and good hygiene are needed to protect you and your family from RWIs and will help stop germs from getting in the pool.
Chlorine and pH are the first defense against germs that can make swimmers sick. Your swimming pool technician should vigilantly monitor chlorine levels and pH, and make adjustments accordingly. The chlorine level in a pool should ideally be maintained between 2 and 4 parts per million (ppm), and should never fall below 1 ppm. The pH should be maintained between 7.2 and 7.8. Keeping the pH in the proper range will help maintain chlorine’s germ-killing power while minimizing skin and eye irritation.
Your pool technician will keep pool cleaning equipment running properly. Filters help remove debris, while pumps circulate clean, chlorinated water to all parts of the pool. In addition, periodic replacement of pool water helps reduce contaminants that are not removed in the treatment process.
† For you “do it yourselfers” out there, I would highly recommend purchasing a copy of “The Ultimate Pool Maintenance Manual” by Terry Tamminen. It contains everything you will ever need to know regarding your pools maintenance.
For further study, here are a few links to what we spoke of:
University of Michigan Study
• http://www.med.umich.edu/yourchild/topics/water.htm
CDC Site
• http://www.cdc.gov/healthywater/swimming/
Kids Health
• http://kidshealth.org/kid/watch/out/swim.html
Recreational Water Illness
• http://www.aquaticnews.com/2011/07/rwi-recreational-water-illness-what-is-it-and-what-can-we-do-to-prevent-it/