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Sean Day
11-10-03, 01:21 PM
Hi

I am rebuilding my current melamine rack and need to throw together a temp rack until the new one is finished.

I have a bunch of mdf and was wondering if it is safe to use? The mdf is raw and I figure I would have to use it for around 2 weeks.

Thanks
Sean

Sean Day
11-10-03, 01:37 PM
I guess I should have said that it will have heat tape running up the back. I am not really looking to spend money to paint it as it will only be temporary.

Invictus
11-10-03, 01:46 PM
MDF will offgas unless you have specifically purchased a formldehyde-free MDF board, which most building supply stores do not carry because its higher cost. If you use MDF, you should seal it. The formaldehyde gas is only dangerous when the humidity rises, so if you have large water dishes or animals that require high humidity, seal the MDF with varathane, epoxy, enamel, or environmentally safe outdoor sealant. Melamine isn't as a high a risk, because most of the board is sealed with the melamine coating.

Sean Day
11-10-03, 01:56 PM
Thanks for the reply Invictus!

It will just be for a rack that the rubbermaids slide into, so no water would come into contact with it.

Would the heat tape heating it also make it let more gas out?

Thanks
Sean

Invictus
11-10-03, 02:34 PM
Yes, it would... because the heat tape also raises ambient humidity if the environment is closed off, such as in a rubbermaid bin. It doesn't have to come in contact with water - just moist air.

Go up to a board of MDF and give it a whiff. Does it smell like wood? A little bit... but mostly it smells like glue. This is the formaldehyde gas. Although I have not seen any kind of scientific data about the effects of this gas on reptiles (hobbyists have been using MDF and melamine for decades without a problem), I would personally side with caution for the MDF, but not necessarily for the melamine. I'd still recommend sealing the MDF.

Sean Day
11-10-03, 02:43 PM
OK thanks. Guess I will pull all the glass tanks out of the attic until I finish the melamine rack.
I HATE TANKS (LOL)

Sean

sapphire_moon
11-10-03, 09:19 PM
Invictus what type of enamel do you suggest? We have protective enamel (from rust-olem) now on the inside of our bp enclosure and it is STILL off gassing.

eyespy
11-10-03, 11:02 PM
The surgeons I work with notice an increased likelihood of kidney disease in animals housed in environments that expose them to longterm low levels of toxins such as formaldehyde, toluene, phenols, and aflatoxins, but have never done an actual study.

I'd play it safe and use a low-VOC epoxy or polyurethane sealant.

JonD
11-13-03, 01:41 PM
You could also use a counter top laminate on that mdf. Any countertop manufactor throws out lots of off cuts and old colors.

Invictus
11-14-03, 04:14 AM
Sapphire, I'm still thoroughly surprised about your paint having that much of a fume problem. I've never personally experienced that much offgassing with enamel-based paints, but then again, I've never subjected them to extreme heat as in a reptile enclosure.

If all you're doing is sealing in the MDF gases, even primer and water-based paint will form enough of a barrier that the formaldehyde can't get through. But this would only be good for a rack system - for the inside of a terrarium, epoxy is by far your best bet. I'm going to see if I have any kind of success with melamine paint as well, but as of this post I can't comment on its effectiveness, or its offgassing.