Hydrolysis splits water molecules (H2O) into H and O atoms creating free radicals. These free radicals form oxidants more powerful
than chlorine: OH- (radical hydroxide), O (atomic oxygen), O3 (ozone), H O2 (hydrogen peroxide) and O2 (oxygen). The advantage of 2
this is that these radicals disinfect within a few seconds and then fall back into water; so no harmful by-products are produced as with chlorine. In addition to these free radicals, a small amount of sodium hypochlorite is made to ensure a residue effect in the pool. This requires only 1.5 grams of salt per litre of water. 

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