Flow hood advice needed

[Kreat]

So i built a 2'x1.5' flowhood (not completely done yet, but a work in progress) and now I have to seal the walls of the box. I used plywood and plexiglass to create a domed in working area so my hands can't move out of the space with the clean air.

I was going to put metal sheeting on the inside, but I've having a really hard time. I wanted to put something on it so it will be easier to clean and disinfect the surfaces.

Any ideas? Is there anything I can paint on? I was thinking polyurethane?

[circumsizzle]

mayb a fiberglass resin would b in order. ask "round and there mayb better results

[Ben Dover]

With several coats of kilzs primer it will get fairly smooth.

Did you use OSB plywood? Painting it will be the best thing for it to help lock out moisture and prevent the wood pilling up.

If it is still not smooth enough for you then you could get the dimensions you need and have a machine or welding shop cut, preferably stainless steel, some metal to size and glue it down.

Or how about more plexiglas? Get the people at the box store to cut it to size. Make them cut pieces until they get it right. It took someone 4 tries to get a rectangle cut right so I could fix a window pane.

[Myc]

Don't use laquer whatever you do! - I did and I regret it every time I forget and drop an alcohol wipe. What a mess.

I wish I'd gone with enamel or even latex
I still have great success with my 'hood - pitted and marred paint surfaces aside.

Just wipe down with Clorox wipes (or similar) all surfaces after running the hood for about 10 min or so.

[Kreat]

I ended up using a sealer for the wood, and it seems to have worked very well! I'll take pictures when I can to show how it looks.

I'm wondering now, what is the proper procedure for using the flowhood? Do I spray bleach in it first, put everything inside, spray everything down, then turn it on for 15 minutes then start my work?

[BuckarooBanzai]

Don't spray anything inside of it.

Turn the fan on and let it run for at least 2 hours before the first use. Let all the nasties in the filter get blown out.

After that, it is best to let a flow hood have at least a 1 hour "run up" period every time you use it. Don't just turn it on and start working.

Are you using a pre-filter? They are very, very helpful.

Once you have a hood running properly, you have a stream of sterile air blowing hard enough to deflect contams in the ambient environment. You do not need to clean the outsides of containers. Just work directly in front of the center of the filter and stay as close to it as possible (without touching it - try to never touch the filter).

The air coming out of sub micron HEPA filter is far more sterile than the cleanest surgical room on this planet. When you do all your work in that stream of air, contamination risks become much, much lower than working in a glove box.

[Kreat]

Thanks for the reply.

I am using a pre-filter so that any of the big nasties will get blocked first.

I will let it run for an hour or so for now on before I use it.

So I guess what I should be doing is this:
Run the box for an hour
Then place everything in side, and start doing my work

And I shouldn't have to worry about surface contact doing any kind of contamination?

When using tools like a scalpel I still want to torch it with my alcohol burner correct?

Thanks for the advice! I love my hood already.

[BuckarooBanzai]

Sounds good.

Surfaces are still dirty, but anything nasty they contain gets blown away at a right angle to the filter. If you hold an agar dish downstream of a dirty jar, contams blow on it. If you hold an agar dish upstream of a dirty jar - the "dirtiness" of the jar is erased by the air flow.

Any time you touch a tool against a dirty surface, always flame it clean.

When changing containers/source material, I always sterilize the tools.

When changing between strains, always sterilize the tools.

Never let your hands get between clean work and the filter. There should always be a totally unobstructed (and short) line between the filter and whatever needs to be sterile.

Flow hoods aren't magic but they CAN drastically improve the success ratios of all sterile work (if ya use 'em right).

[Kreat]

This sounds great! I'm so excited. I just purchased a wickless two head alcohol burner, a new scalpel and some blades! Agar work here I come!

[BuckarooBanzai]

Are you planning make your own agar plates?

This is how I do it:
http://forums.mycotopia.net/agar-str...zai-style.html (Agar for the masses - Banzai Style!)