Set out the station before you start
Hands, then bench, then materials. Learn why the order of those three steps is deliberate and why nobody should be walking to a cupboard with a loaded loop.
- Treat a surface before clean things land on it: Disinfecting after the plates are already out means the plates spent that time on an untreated bench.
- Once your hands are loaded you should not be walking: Anything you have to fetch mid procedure is fetched by a person carrying a culture. The fix is to fetch it beforehand.
Prerequisites are inferred: pending teacher review.
Re-learn the skill with worked practice and clear examples.
Now handle the mid procedure walk, and the arrangement of the reagents themselves.
Why is walking to a cupboard partway through this procedure worse here than in most laboratory work?
Reviewed- A.The bench you disinfected would have dried out before you got back to it
- B.Your gloves have touched a culture, and you take that with you
- C.It wastes time that the plates waiting in the incubator cannot spare
- D.The alcohol lamp would have to be put out and then relit every single time
Show the worked solution ▾
Answer: B. Your gloves have touched a culture, and you take that with you
- Step 1: Ask what is on your hands: Gloves that have been in contact with a patient sample.
- Step 2: Ask what a walk does with that: Puts it on a door handle, a drawer, and whatever else you touch on the way.
Why it's right: Leaving the station means taking whatever is on your gloves to every surface between here and the cupboard. Those surfaces are not part of anybody's cleanup plan.
- A: Letting the disinfectant dry is fine, and a dry treated bench is still a treated bench.
- C: The plates are not in the incubator yet, and a few minutes would not matter to them if they were.
- D: Putting a lamp out before you leave is right, and it is an inconvenience rather than the reason this matters.
Aligned to Handling, Preparation, Storage and Disposal · reading level ~grade 9
The Gram stain uses four reagents in a fixed order. How should the bottles be set out on the bench?
Reviewed- A.Alphabetically, so that any one bottle is easy to find quickly
- B.Grouped by the size of the bottle so the rack sits level
- C.Left to right, in the order the procedure actually uses them
- D.Wherever there is room on the bench, since each one is labelled
Show the worked solution ▾
Answer: C. Left to right, in the order the procedure actually uses them
- Step 1: Ask what the risk is during the run: Reaching for the wrong bottle while a timed step is going.
- Step 2: Ask what removes that risk: A layout that matches the sequence, so the next bottle is always the next one along.
Why it's right: The order of these reagents is what produces the result, and a bottle picked up out of sequence ruins the slide. Laying them out in working order means your hand finds the right one without you having to read four labels mid step.
- A: Alphabetical order has nothing to do with the sequence, so it puts you at risk of reaching for the wrong one at speed.
- B: Bottle size is about the rack rather than about the procedure, and a tidy rack in the wrong order is still the wrong order.
- D: Labels help when you have time to read them, and the moment you most need to be right is the moment you are least likely to stop and read.
Aligned to Handling, Preparation, Storage and Disposal · reading level ~grade 9
- A group lines the stain bottles up in sequence before anybody puts gloves on.
Fill these in as you work through the lesson.
- Work area (disinfected before the materials arrive):
- Waste receiver (set out first, not fetched later):
- Reagent order (laid out in the order the protocol uses them):
- Loaded loop (a reason not to walk anywhere):
Wash your , disinfect your work , and only then collect your plates, samples and loops. Set the four stain bottles out in the the procedure uses them, and put the container down before you need it.
- Say what the wash, disinfect, collect order achieves.
- Explain why walking to a cupboard mid procedure is a problem here.
- Describe how the stain bottles should be arranged.
You wash your hands, wipe the bench, then collect three plates, three samples and the loops in one trip. The disinfectant beaker goes down at the same time, so the first used slide has somewhere to go.