Chamber with temperature and humidity control

[queiry]

I have a metal chamber that is 43in x 29in (32in tall), where the bottom is covered with about 3in of sand to grow bacteria. I want to be able to control temperature (5-50C) and humidity (10-90%), and I need help in designing the system. I would also like to be able to cycle the changes throughout the day to mimic day/night conditions, e.g. low T high H at night, high T low H during the day.

Secondly, I need to have some UV lamps (UVA & UVB) in there, to approximate the effect of the sun since UV plays a role in bacterial growth.

Nothing needs to be precise, I’m just trying to replicate growing conditions in the desert. And I don’t have the budget to buy a fancy chamber, so I’m looking for a solution that I can throw together. If the unit(s) is small enough, it can live inside the chamber, otherwise I can set it outside.

My engineering training is more theoretical, so I have no experience in basic design/equipment.

I appreciate any feedback, even if it’s to say it can’t be done, or that I need to narrow my ranges.

Thanks!

 

[kenvlach]

queiry,
There are ASTM, ISO, SAE & UL tests for accelerated exposure testing of painted metals, plastics, etc. to UV, humidity, etc. Many cyclic tests similar tto your description. Look at some of the environmental testing chambers from these suppliers:

http://www.astm.org/cgi-bin/SoftCar...1+-P+TERM+D4587+searchresults_designation.frm

If you cannot afford new equipment, there are plenty of used equipment dealers, e.g.:
Los Angeles

http://www.lre.com/test/lre-mainpage/lre-mainpage.asp

Phoenix

http://www.asset-exchange.com/

MARKHAM, ONTARIO

http://www.labequip.com/

 

[queiry]

Thanks for the links. I hadn't considered used equipment.

Even if I don't find exactly what I need, I might find an environmental chamber, that I could modify for use with UV bulbs.

I'll look at the links more closely, and see if they're economically viable.

Thanks!

 

[queiry]

In the meantime, if anyone else has suggestions on modifying my current chamber (or even roughly building a new one), I welcome ideas.