Death / Killing loss of ability of microorganism to multiply under any knownconditions

Sterilization complete killing or removal of all living organisms from a particular location or material 1. incineration 2. heat treatment 3. chemical agents 4. ionizing radiation 5. filtration

Pasteurization heat at a temperature sufficient to inactivate important pathogenic organisms in liquid (most vegetative bacteria) water, milk 74 0 C for 3-5 sec or 62 0 C for 30 mins spore are not killed

Disinfection destruction of pathogenic microorganisms by process that fail to meet criteria for sterilization bacterial spore may resistant to chemical agents (disinfectants) High level disinfection (all organisms except bacterial spores) Low level disinfection (except TB, bacterial spores, some virus)

1. Solubility- alcohol 2. Noncorrosive- should not attack metal 3. Penetration- penetrate rapidly and efficiently 4. Nontoxic to higher life- man and other animals life 5. Stability- in the presence of organic matter 6. Deodoring power 7. Germicidal power - should kill bacteria in dilute soln in normal temperature 8. Power to remove dirt 9. Economy Characteristics of an ideal disinfectant

Antiseptics chemical agents that can be used on body surfaces such as skin, vaginal tract to reduce the numbers of normal flora and pathogenic contaminants. lower toxicity than disinfectants. less active in killing vegetative organisms.

Sanitization used primarily in housekeeping and food preparation contexts action between disinfection and cleanliness

Asepsis processes designed to prevent microorganisms from reaching a protected environment applied in operating room, microbiology laboratory characterized by absence of pathogenic microbes Sepsis characterized by the presence of pathogenic microbes in living tissue

Germiostatic bactericidal, fungicidal having the property to inhibiting organisms multification. multification resumes upon removal of the agents. Germicidal having the property of killing microorganisms. no longer reproduce even after removing from contact with the agent. bacteriostatic

Microbial killing killing of bacteria by heat, radiation,chemicals usually exponential with time starting population 10 6 / ml10 5 / ml (after 5 mins) 10 0 / ml (after 30 mins) slope of curve vary with effectiveness of killing process, nature of microbes, agents, conc n (in case of disinfectant) and temperature more resistant mutants resistance to inactivation the later stages of the curve are flattened