The disinfection process does not take place at once but is a gradual operation in which the number of organisms killed in unit time is greater at the beginning and becomes less and less as the exposure period is increased. If the numbers of survivors in unit volume are plotted against time, the points fall on smooth curves. If the [...]
The method generally employed for the evaluation of germicides is to rate them according to their phenol coefficients. In addition to this, a number of newer methods have been proposed, which are designed to measure the toxicity of germicides for tissue as well as for the test bacteria. 1. Phenol-Coefficient Method: The phenol-coefficient test was first proposed by Rideal and [...]
Here is a list of fifteen main chemical agents that can kill infection causing organisms:- 1. Preservatives 2. Acids 3. Nitrates and Nitrites 4. Alkalies 5. Salts 6. Reducing Agents 7. Oxidizing Agents 8. Phenols and Cresols 9. Alcohols 10. Glycols 11. Dyes 12. Mercury Compounds 13. Soaps 14. Surface-active Agents and Synthetic Detergents 15. Sulfonamides. Chemical Agent # 1. [...]