Mix bleach to the right ppm for sanitizing.
Household bleach is a solution of sodium hypochlorite (NaOCl), typically 5.25-8.25%. For food contact surface sanitizing, the FDA requires 200 ppm; for general disinfection, 500-1000 ppm; for blood/body fluid cleanup, 1000-5000 ppm. The dilution formula: bleach volume = (target ppm × total volume) / (bleach concentration × 10,000). Important: bleach degrades over time — an opened bottle loses ~20% potency per year. Use cold water (hot water decomposes NaOCl). Never mix bleach with ammonia (produces toxic chloramine gas) or acids (releases chlorine gas). Contact time matters: most surfaces need 1-10 minutes of wet contact for disinfection. Rinse food-contact surfaces after sanitizing with bleach above 200 ppm.