The Zipcode for Poland is. Poland is a village of Mahoning, Ohio in the Great Lakes region of the USA. It is located about 141 miles east-northeast of OH's capital city of Columbus.In the most recent US census the population of Poland was 2548. City/Zip code State.oland is a village of Mahoning, Ohio in the Great Lakes region of the USA. It is located about 141 miles east-northeast of OH's capital city of Columbus. In the most recent US census the population of Poland was 2548.
pH. The pH is a measure of the acidity of the water. The pH scale goes from 0 to 14, where pH 7 is neutral. If the pH is above 7, the water is basic; if it is below 7 the water is acid. The optimum pH for pool water is 7.4, since this is the same as the pH in human eyes and mucous membranes. A pH of 7.4 also gives good chlorine disinfection.
Swim while chlorine levels are still at safe levels. Swimming helps lower chlorine, but only try this if chlorine is at slightly high (4 ppm). Experts disagree on how much chlorine is dangerous to swimmers. Public pools often shut down at 10ppm, while some pools use a 5ppm limit to be extra safe.