What’s a Clean Air Flowhood?

Probably you observed that a piece of bread wrapped in a container  and left at room temp in the middle of summer for several days gets moldy. Usually we may see one or several mold types (green, bluish-green or black molds). This means that mold spores landed on it and in presence of moisture, oxygen and heat they started to consume the nutritious bread. This tells us that in a particular habitat there’s competition between organisms for food and resources. But what would happen if we would offer this piece of bread to one organism? In this case we wouldn’t have competition. And because we humans often like to play God  we can twist things up and sterilize the bread then we transfer it into an environment –FREE of microorganisms. This environment is ensured by a flow hood equipped with micron filters able to filter micro-organisms living the air sterile. Here we inoculate it with the desired fungus [e.g., oyster mushrooms, shiitakes, buttons, etc] then we transfer the jar to a grow room for incubation.

Now, manipulating the sterilized bread and transferring the fungus onto it is a challenge because it’s not easy to avoid any possible competitors to land on that piece of bread in the surrounding non-clean air. I just gave you an example but in reality we grow the fungus on grain, sawdust, wood-chips, or synthetic materials. If we would use bread instead we would lower the spawn making success rate because sugars are freely exposed to any competitor organism; however, in order to avoid this we will use sugars closed into ‘capsules’ –simply called grain (wheat, oats, barley, sorghum, maize, rice, etc).

A Flow Hood it’s a box free of microorganisms –provides a sterile environment and allows you to perform fungus or bacterial tissue transfers. It has a wide application espeacially in microbiology.

In mycology this box is used mostly for making media, and cloning mushroom mycelia. For you to understand how powerful the cloning concept is, I will briefly explain how it works: you can actually clone a product in infinite samples with very little investment. Some huge corporate companies are using the exact same principle with great success making millions $/year [see Sylvan.com or Amycel.com -these are companies that produce mushroom spawn for mushroom growers]. This is also a very important tool that every serious mushroom growers has at his farm so they can produce spawn with it and inoculate substrates in the mushroom growing process. It is also widely used by mushroom enthusiasts willing to experiment with fungus mycelium.

The problem

Although this magic box is widely used in mycology and other industrial fields mainly it has two disadvantages:

  • Can be expensive – the cost of such a unit starts from $500 to $4500 or more (shipping not incuded)
  • It’s a health risk –it’s equipped with high efficiency particulate air filters capable to filter the air at a rate of 99.97%. However, these filters are made out of fiberglass which represents a risk factor for all of those working with these units. Why? Because they may release fiberglass particles.

The solution

You build it and customize it how you wish and you’ll cut costs, and avoid possible health complications. I built 4 flowhoods so far and I’m very glad I did that. With some guidance you can also build your own fiberglass-Free flowhood. You need to know how to build one the right way otherwhise you might run into contamination issues due to poor fan performance, filter type, or no fan-filter match.

Without a flowhood you won’t be able to make a quality spawn. Spawn can actually be made without a flowhood but you don’t really want to get into that 🙂 As a mushroom grower you will use it to grow the mushrooms that need additional nutrinet supplementation such as various types of bran (used to increase overal yield). These supplements when applied without propper disinfection will spoil all your substate and you won’t be able to grow mushrooms like shiitake, lions’mane, chestnut mushrooms, shimenji, nameko, enoki, mitake, and so forth. You could try to grow these in the absence of a flowhood but it’s going to be tricky. So, I hope you understand how valuable is a device like this fr a mushroom enthusiast.

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There’s a hidden danger inside your flowhood

I’ve started to use a commercial flowhood in 2006 and at that time I didn’t know what’s made of. For me it was just a box that cleans up the air that mycologists use for fungus tissue transfers, cloning, spawn making, mushroom growing and some other related operations. For four years I’ve been playing with this box without knowing that I was breathing in and eating fiberglass particles. Accidently, in 2010 I discovered this while manipulating with my bare hands a HEPA filter that I was going to use to build my first flowhood (the light was on and my finger prints were shiny). This was when I questioned myself what was that filter made of and started to look into it a little, but this wasn’t enough because at that time I said myself, what the heck, everybody is using it therefore it should be fine.

After 3 years, I’ve built another flowhood and placed a HEPA filter in it and used that for a while until I had to analyse a mycelium fragment taken from a pure culture under the flowhood which I was going to check under a microscope. What I saw it was shocking: a bunch of sharp needles fused together and scattered all over my preparate mixed with fungus mycelium. At first I tought that could be some glass fragments originating from the slide and wanted to confirm that by checking another empty slide under the microscope (that wasn’t placed under the flowhood). I didn’t see anything, then I placed the slide under the flowhood again and re-checked that under the microscope, this time I saw again the sharp particles that I labeled fiberglass particles originating from my flowhood’s HEPA filter.

It was terrifying to realize that those prickles could get into my lungs or stomach, right after that I knew how exposed I’ve been this whole time.

This looks very much with what I saw under the microscope -too bad that I don’t have a picture to show you exactly what I saw. Photo credits: etc.usf.edu

These fiberglass particles were shiny in the sun light or when exposed to indoor light [the stronger the light the better] and would remain on my finger tips even after hand washing, they would go off only when I would use a brush. For a while I used disposable gloves and a simple mask to protect myself from this -as a mycologist this was an essential equipment that I was using quite often. The gloves were fine, the mask wasn’t because it didn’t have the ability to filter fiberglass particles so I was still exposed. I was trying to convince myself that this isn’t dangerous and maybe I’m just exagerating because every one out there is using HEPA filters in their flowhoods. I took several samples from other flowhoods as well and pretty soon I realized that all of em were releasing these particles [especially when hit, shaken or transported]. I dug into literature to check the health hazards that I’ve been exposed to, read about controversial stuff on this topic, and studies highlighting tumor risks, expoure time, particle size related things..This is just a tiny sample of what you can see out there:

I was taking very often showers to wash away the fiberglass from my hair, face, hands, and the rest of my body. Only the thought that those prickles would get anywhere in the lab or in the house (door handles, food, tables, chlothing, etc) was crazy -I wasn’t enjoying anymore what I was doing. All this made me slowly isolate and soon distroy my flowhood. A mycologist without a flowhood is pretty much like the skies without a moon, so I had to find a solution to this.

Many of you’ve purchased commercial clean-air flowhoods. The’re not cheap either and the bigger and heavier the flowhood the more you need to pay for shipping. Then, you place your box in the bedroom, kitchen, closed, or so turn it on and spread the crap everywhere in your house or lab and you don’t even know it, cuz see..nobody is telling you about it. You need to do your own homework if you really care about your health, (if you don’t that’s fine -this is just a message for those who care).

To check fiberglass particles simply play around without gloves on with some petri plates under your flowhood, then turn on the strongest light that you have around and check your palms, twist them to see any tiny reflections of light when held against it. You can do the same outside in the sunlight. Another way to check for fiberglass particles is to pour some water on your flowhood work bench, mix it up to wash the surface and place 1-2 drops on a microscope slide, then check for prickles [use the 40 -100 x magnifier]. If you see anything you’re also exposed, repeat the test and start to do something about it (if you care). The worst thing you can do is to accept and continue working with it as is or even if you protect yourself with gloves and mask at one point you might find yourself eating and preparing your food with disposable gloves on because you don’t want your fiberglas infected hands to touch your food and when you’ll get to this point is just the start for you getting paranoic about it. It just sucks, I know! but you need to be aware of this hidden danger. Toss the damn thing out to the dumpster or change the filter with something else or go backwards and better get a glovebox or simply build a new flowhood -for this you can check my course on how to build a fiberglass-FREE flowhood if you want.. You don’t have to take my course for this, but go do yor own homework to find a new way to change something so you can get rid of those nasty fiberglass particles. Do something, change your life! I just can’t believe that for 5 years or so I was exposed to this crap because nobody told me. Could be the same old story as happent when people introduced asbestos and DDT, they worked, were efficient everybody embraced them, loved them until they realized they were slow killers. Fiberglass products might end up like this one day.

I know this is a bad message, but hey let’s be realistic about it -it’s better for you to be aware about it rather than working with it and one day get sick without knowing why. Please spread the word about this to your buddies that don’t know about it, they simply have the right to know.

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