Australia's Science Forum

A teacher wants to open an agar plate that's been growing bacteria @ 30degC, to view under microscope. I don't have a risk assesessment, but surely that's not right?

Firstly its a big no no.. to open the plates. ( unless you are culturing specific bacteria on certain media which we dont usually do at school). You dont know what your dealing with!
You can view under the steroscope with it still sealed up.
If you veiw the plate under a microscope you wont see anything, you need to make a slide and stain it for specific bacteria eg grams stain to veiw cocci or rod shapes. they are usually very small and better to do oil emmersion.

They shouldnt be doing that prac without having a Risk Assessment .
The risk assessment will cite opening agarplates as a biohazard risk.
It will aslo say, do not open plates, unless under fume hood, gloves etc , wash areas with metho etc, and other controls in place.

If theres this conflict of procedures re any prac....Always ask the teacher if you can read through their risk assessment for that prac.
That usually get s the message across

I talked him out of it by using the magic words 'risk assessment'.

Just troll the net for some piccies of the usual range of human flora, and any other usual culprits on an agar plate. Then present the class with the piccies after they have grown their own cultures. Then they can see what's likely to be there, without the hazard.

Hey Xenon,

Have a look at the post 'bacteria' . It has a really good download that showed pictures of bacteria growing on an agar plate that is labelled. You can show it as a slide show.

Well done Xe !

Those certainly are "magic words"

I checked out that bacteria set of pictures and it is great. Thanks Kiah.
It is from Bindabadgie (spelling may not be correct) from around Aug 20 last year
Rosalie (another one)