Hesperian Health Guides

Hesperian Health Guides

Disinfecting with Chemicals



HealthWiki > A Community Guide to Environmental Health > Chapter 19: Health Care Waste > Disinfecting with Chemicals

A health worker covers her mouth as fumes come from a nearby cannister.
Chemical fumes can be harmful!

All chemicals used to disinfect can be harmful and need to be used with great care. Some chemicals commonly used to disinfect include hydrogen peroxide (6%), chlorine bleach, ethanol (70%), and isopropyl alcohol (70% to 90%).

Many common cleaning and disinfecting products contain glutaraldehyde or formaldehyde. Regular exposure to glutaraldehyde and formaldehyde can cause cancer and death. These chemicals should not be used. (See “Disinfecting with safer chemicals” and Safe Disposal of Chemical Waste.)

Many health centers use these guidelines for safety when using chemicals:

  • Use chemical disinfectants outside, or in well-ventilated rooms where there is a good exhaust fan.
  • Use only the amount of chemical disinfectant needed to do the job.
  • Wear gloves, safety glasses, a mask, and protective clothing to protect your skin, eyes, and breathing when using or disposing of chemicals.
  • Store disinfecting chemicals in their proper containers. Label the containers. Do not reuse those containers for anything else.
  • Do not store or mix chemicals in water buckets, or containers or bottles that may be used for food or drinks.
  • Keep chemical containers tightly closed and stored upright. Check them for breaks, leaks, and weak spots.


Wastes that do not need chemical disinfection

It is often thought that body parts need to be disinfected with chemicals. But body parts, including the placenta (afterbirth) and umbilical cord, are most easily disposed of by putting them in a latrine or burying them deep in the ground. In many communities, burying the afterbirth is an important ritual. If it is done safely, burial is also a good way to protect the community from germs that may grow in the afterbirth or other body parts. (See Disposing of Infectious Waste).

Disinfecting with safer chemicals

Including us!
This stuff is great! It kills everything.
When choosing a product, ask:
Is it harmful? Is it difficult to
dispose of safely?

Some health centers use cleaning products that contain harmful chemicals, such as glutaraldehyde, to disinfect and clean. But surfaces in health centers can be kept clean and germ-free by using less dangerous and less costly cleaning products. Hot water and soap is effective for routine cleaning of surfaces such as floors, walls, and furniture.

In areas where people with infectious diseases wait or are treated, it is important to use a stronger disinfectant to prevent the spread of disease. Hydrogen peroxide solutions that contain orange oil and other natural oils are effective for disinfecting floors and surfaces. They do not cause health problems and do not have to be treated before disposal. A safe disinfecting solution can also be made with vinegar and hydrogen peroxide.

How to make a safe disinfecting solution

Mix together equal amounts of white vinegar and hydrogen peroxide. (A 3% peroxide solution is common, but 6% is better.) Mix only as much as you need for one day. Keep it in a closed container.

Pour a small amount of the mixture on a wiping cloth and scrub the surface to be disinfected with strong rubbing motion.

This mixture is best for use on tabletops, bed railings, and other surfaces.

Disinfecting with bleach

Many health centers use bleach to disinfect surfaces such as walls, floors, and tables. Care must be taken when disinfecting with bleach because it can cause harm to your skin and eyes if it splashes on you, and the fumes are dangerous when breathed in. Adding white vinegar to the bleach makes it an even more effective disinfectant.

How to make a disinfecting solution of 5% bleach

If your bleach says: Use:
5% available chlorine Only bleach
10% available chlorine Add 1 part bleach to 1 part water
15% available chlorine Add 1 part bleach to 2 parts water

If you add 1 cup of white vinegar to a gallon of 5% bleach solution, it will disinfect better. Mix just enough solution for one day. Do not use it again the next day. It will not be strong enough to kill germs any more. To get rid of used bleach, see “Disposing of liquid waste.”

Use a bleach bucket

Keep a bleach bucket wherever there is infectious waste such as used bandages, cotton swabs, gloves, and blood bags. Prepare the bleach bucket every day, or before each shift if you make a lot of waste. You may want one bleach bucket for waste to be disposed of and a different one for disinfecting tools and equipment to be reused.

The bucket should always contain enough bleach solution to completely cover the materials. The materials must stay in the bleach for at least 10 minutes. Keep a tight-fitting cover on the bleach bucket to prevent spills, and to keep the bleach solution strong enough to disinfect. Uncovered, the chlorine will evaporate away.

Gloves, syringes, IV bottles, tubing, and other things that are not intended to be reused should be cut into pieces after taking them out of the bleach bucket.

How to make a bleach bucket

a man makes a bleach bucket.

One way to safely disinfect with bleach is to use a bleach bucket. A bleach bucket has 2 parts: a bucket or container that holds bleach solution, and a smaller inner container or basket with many small holes like a strainer or loose woven basket that holds the wastes. A bleach bucket must also have a tight-fitting cover. To prepare a bleach bucket:

Make a 5% bleach solution. The main bucket should be at least ½ full of the bleach solution.

Place the smaller container, strainer, or basket inside the main bucket so the bleach solution passes through the holes. Make sure the inner container does not float on top of the solution, but that the bleach solution passes though the holes so it completely covers the waste materials.

IMPORTANT! Bleach should never be mixed with other chemicals, especially ammonia. Bleach and ammonia mixed together will produce a toxic gas that can cause death if breathed in, and enough heat to cause an explosion. Always wash carefully after handling bleach.


In the past, many hospitals used carbolic acid to sterilize sheets. This is only necessary for the sheets of people being treated for burns. To disinfect bed linens and clothes, soak them in a bleach bucket for 10 minutes before washing with hot water and soap. Use gloves when taking them out of the bleach.

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