Chlorine as a Disinfectant

This guidance has been adapted from the following CDC, MSF and WHO documents.

Note that these documents predominantly refer to the use of chlorine with respect to VHF (Ebola) and influenza viruses, however the key principles of how to prepare different strength preparations remain the same.

Environmental cleaning is one of several recommended methods to reduce transmission of deadly germs among patients and healthcare personnel.

Chlorine solutions are oxidative chemicals and have broad-spectrum activity against a wide variety of microorganisms, from viruses to protozoa.

Preparation and Use

  • Bleach (sodium hypochlorite) solutions are produced in different concentrations in different parts of the world, and solution strength can vary between 2% and 12%.
  • The active┬áchlorine content must always be checked on the product packaging in order to adjust the dilution if necessary.
  • STOP: Always read the product literature and if in doubt seek advice from the manufacturer
  • The concentration required depends on the amount of organic material present (how clean/unclean the surface is).
  • Do not bring dry products, particularly HTH and chlorinated lime, into contact with organic materials as there may be a risk of explosion.
  • Avoid inhaling vapours and dust when opening or handling the containers.
  • Prepare solutions with cold water in non-metallic containers.
  • Clear water should be used because organic matter destroys chlorine.
  • Bleach solutions give off chlorine. Prepare them in a well ventilated area.
  • A deposit in HTH solutions and chlorinated lime solutions is normal (use only the supernatant).
  • Handle concentrated products with caution (avoid jolts and exposure to high temperatures or flames).
  • 1:10 bleach solution is caustic. Avoid direct contact with skin and eyes.

The following table is taken from MSF’s clinical guidelines. It explains how to prepare different strength chlorine solutions and indicates when these should be used in the health centre.

Remember: Chlorine solutions gradually lose strength, and therefore freshly diluted solutions must be prepared daily.