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· Close windows and doors to reduce draughts and prevent sudden movements which might disturb the air.
· Make transfers over a disinfected surface. Ethanol disinfection is recommended because of its rapid action. If the bench surface is difficult to clean, cover the bench with a sheet of tough material which is more easily disinfected.
· Start the operations only when all apparatus and materials are within immediate reach.
· Complete all operations as quickly as possible, but without any hurry.
· Vessels must be open for the minimum amount of time possible.
· While vessels are open, all work must be done close to a Bunsen burner flame where air currents are drawn upwards.
· On opening a test tube or bottle, the neck must be immediately warmed by flaming (see below) with the vessel held as near to horizontal as possible and so that any movement of air is outwards from the vessel.
· During manipulations involving a Petri dish, limit exposure of the sterile inner surfaces to contamination from the air.
· The parts of sterile pipettes which will be put into cultures or sterile vessels must not be touched or allowed to come into contact with other non-sterile surfaces, such as clothing, the surface of the working area, or the outside of bottles/ test tubes.
· All items which come into contact with microorganisms must be sterilized before and after each such exposure. This could be either by the technical team preparing for and clearing up after a piece of practical work (for example, in the case of glassware to be used), or by the worker during the course of the practical (for example, in flaming a wire loop).
Titany answered the question on September 10, 2021 at 12:23
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