Bleach Sanitizing Solution: Your Best-Fit Cleaner

Bleach Sanitizing Solution: Your Best-Fit Cleaner

Diluted household bleach (sodium hypochlorite) is a widely used disinfectant for hard, nonporous surfaces, but only when it is measured, timed and used alone. The CDC's household guidance is 5 tablespoons (1/3 cup) of bleach per gallon of room-temperature water, or 4 teaspoons per quart, and it assumes bleach with 5%-9% sodium hypochlorite; the CDC says not to use products outside that range or with no percentage listed. If your bottle is a concentrated or specialty formula with its own disinfecting directions, follow the bottle. Use room-temperature water, as the CDC specifies.

The steps matter as much as the ratio. Clean the surface first with soap and water, because dirt uses up bleach and shields germs. Then apply the bleach solution so the surface stays visibly wet for the contact time; the CDC says at least 1 minute, and some labels require longer. Follow the label on rinsing food-contact surfaces, and let everything air dry. The CDC says to make a new diluted solution daily, because a bleach solution is not as effective after more than 24 hours mixed with water. Store it in a labeled bottle away from heat and sunlight, and ventilate: the CDC advises opening windows and doors when using bleach indoors.

Where not to use it: check the maker's care guide before using bleach on natural stone, unsealed or waxed wood, stainless steel, aluminum, brass or copper, since bleach is known to corrode some metals and damage finishes. It can also discolor colored grout, fabric, painted surfaces and carpet; Shaw Floors lists bleaches among products that can discolor or dissolve carpet fibers. Do not use bleach in a small, closed room without airflow, and keep pets and children out of the area until it has been rinsed and dried. If a soft or porous surface has widespread mold, bleach is not the right fix, so follow guidance for larger mold problems.

To mix it safely, dilute only with room-temperature water and never combine bleach with any other product; the CDC says never to mix household bleach or any disinfectant with any other cleaners or disinfectants. Bleach plus ammonia forms toxic chloramine gas, and bleach plus vinegar or other acids releases chlorine gas, as the Washington State Department of Health and the Missouri Poison Center explain. Transport Canada's CANUTEC warns that alcohol-based cleaners mixed with bleach can create chloroform, and Washington State notes bleach also reacts with hydrogen peroxide. Do not spray it on a surface still wet with another cleaner. If a mix goes wrong, move to fresh air right away, open windows, and call Poison Help at 1-800-222-1222 (America's Poison Centers, US). Call 911 for trouble breathing, chest pain, or collapse. Wear gloves, keep windows open, and store bleach upright, tightly closed and out of reach of children and pets.

Source: CDC, Cleaning and Disinfecting with Bleach; Washington State Department of Health, Dangers of Mixing Bleach with Cleaners; Missouri Poison Center, Some Things Just Don't Mix; Transport Canada CANUTEC, Improper mixing of common household cleaning products; Shaw Floors, Carpet Care and Maintenance. Note: CDC ratio assumes 5%-9% bleach, so confirm the percentage and any label directions on your bottle.

General household-cleaning guidance, not medical or professional advice. The label on your product always wins; never mix cleaning products. For a poisoning emergency call Poison Help at 1-800-222-1222 (US), or 911 if someone has trouble breathing.

How Bleach sanitizing solution compares

* Illustrative starting amounts and notes, rounded -- use the calculators below for your exact numbers, and always check your product label.