Bleach

• Products containing bleach are effective at killing a large variety of bacteria. They are not so useful against viruses. However, the ability of bleach to disinfect degrades over time.
  
  

Formaldehyde

• Formaldehyde is good against bacteria, but needs to be in contact with the surface for two to 12 hours. Thus, it is usually used on objects that can be immersed in it.
  
  

Hydrogen Peroxide

• Hydrogen perodide is great because it is effective against bacteria and viruses. It is often poured on open wounds in the skin to disinfect and prevent future infection.
  
  

Alcohol

• All alcohol can be used as a disinfectant. However, for most medical and other purposes, isopropyl, or "rubbing alcohol," is used. It is effective against bacteria and some viruses.
  
  

Halogenated Tertiary Amines

• Halogenated tertiary amines are available in products, such as Enviroclens, a substance used to clean bird cages. It not only kills bacteria and viruses, but algae and fungus as well.