“Salt water tubs” are not a new thing. They were popular in the eighties and early nineties and fell out of favor due to a number of factors including cost and the corrosive nature of salt. Recently, however, “salt water” spas have become a highly-advertised option creating a resurgence in their popularity. However, with all the hype, most likely a “salt water hot tub” is not what you think.
Many people imagine that a “salt water hot tub” is filled with the equivalent of clean ocean water. Others believe it is something like bath water with epsom salts. And most people mistakenly think that salt water hot tubs do not use chlorine. Saltwater hot tubs and pools are not actually chlorine-free; they simply utilize added salt and a chlorine generator to make the chlorine right in your tub, instead of you directly adding chlorine to the water.
A chlorine generator (also known as salt cell, salt generator, salt chlorinator, salt system, or SWG) uses electrolysis and dissolved salt to produce a form of chlorine – essentially the same chlorine sanitizing agent that has commonly been used in pools and hot tubs for decades.
Chlorination is the most widely used method for disinfecting water supplies in the United States. According to the National Institute of Health, “chlorination is the standard of disinfection against which others are compared.” The near universal adoption of this method can be attributed to its high performance as a disinfectant, which has been established by decades of use. It has been so successful that we no longer worry about epidemics of waterborne diseases. Water safety is now virtually taken for granted.
Simply put, chlorine is used to disinfect water because it works.