All of the following steps should take you a total of no more than 15 seconds or so. Practice first with non-sterile equipment. Then practice again a few more times. Reasons for doing the various movements are shown in purple.
 | 1. How to take a pipet from a can. The can is on its side, and you lift one of the top pipets out by its mouthpiece end only. Do not drag the pipet out so that its delivery end touches the mouthpiece ends of the remaining pipets. Do not touch the pointed delivery end unless you have previously sterilized your hand by toasting it over a flame until that nice steak smell become strongly evident. No other way works fail-safe for sterilizing hands. After sterilization, the cans are always held horizontally to prevent dust from moving down toward the delivery ends. The pipets are lifted out of the cans because the mouthpiece ends of the remaining pipets are possibly contaminated by your groping for the pipet you are now removing. It should be obvious that you NEVER touch the delivery ends because they go into otherwise sterile or axenic containers. |
 | 2. Inserting the pipet into the bulb. This may seem like a simple operation but most students do it wrong because they grab the pipette too near the delivery end, or else, when pushing it into the bulb, the delivery end touches their clothing, the lab bench or other non-sterile items.All this is very important because in many cases if just one single viable cell of an environmental contaminant is transferred, the experiment is ruined. |
 | 3. Taking of top of tube or bottle or flask with your little finger of the pipetting hand. This is a little tricky at first, but practice, practice, practice. If the cap must be screwed off, then catch the cap in the little finger and twist the container. NEVER set the top of the container down. Note that when the cap is caught in the crook of the little finger it is almost impossible to turn upside down so that a dust particle might settle into it. For the same reason, the main container is usually held at an angle to minimize its opening to falling dust. |
 | 4. Then flame the lip of the container. Most of the time airborne contaminants will have landed near the mouth of the container. The flame will incinerate them. The flaming will also heat the walls of the container so that contaminants that have settled on the inside will also likely be killed. However, be careful! Too intense a heating might crack a glass container or melt a plastic one. |
 | 5. Draw up the requisite volume from the container. Please, PLEASE practice pipetting prior to even beginning starting this page. |
| 6. Flame the lip of the container before closing. |
| 7. Replace the lid by pushing the container into the cap that is still being held by the little finger, or by twisting the container into a screw-on cap. But be careful! The lip of the container is hot, and if your aim is faulty, you may end up with a circular brand on the side of your hand, and a blood curdling scream that with scare others in the room causing them to drop things with ensuing chaos. |
Figures used with permission of the publisher of Pierce & Leboffe: Exercises for the Micribiology Laboratory
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