You can go online at Costco.com and apply for a Costco Membership there by adding it to your shopping cart if you are shopping for the first time. Your membership card will be mailed to you within 7-10 days but you can actually shop at the online store immediately.
The three most common chlorine-containing substances used in water treatment are chlorine gas, sodium hypochlorite, and calcium hypochlorite.
Major uses Large amounts of chlorine are produced for use as disinfectants and bleach for both domesticand industrial purposes, and it is also widely used to disinfect drinking-water and swimming-pool water and to control bacteria and odours in the food industry (3,4).