I got very very sick when I went camping and had to "turtle" in the Hybrid or camp in spring or fall in the Cabin A. When I ran the same test on the Cabin A that FEMA and Sierra Club ran on the FEMA Trailers (I was ahving most of the same symptoms and already knew I was chemically sensative) When I got the results back, the formaldahydes were 5 times what they should be for a person like me with Asthma and chemical sensativities. Aliner, the maker of the Cabin A finally acknowledged that the formaldahydes were there and in large quantities. I had already bought a Fantastic Vent and paid to have it installed. This helped immensely in the Cabin A. Aliner sent me a check for more than I paid for the Vent and installation (not a lot more, but it almost paid for me getting a new vent fan and having it installed in the Bantam. I had the vent covers put back on, without the screens (blocks air flow). There is also another upside to the Fantastic Vent, if left on most of the time (I keep both trailers plugged up for Fridge and Vent fans), the trailers are virtually dust free, the dust gets trapped in the screen and then when the screen is popped out and washed, the dust goes down the drain (or back on the ground if I use the outside showers). If I use a plastic bag to surround the screen when I popup it off, there is little dust released back into the trailer. Dust is one of the things that get me also. I can now camp for days in the 2 trailers and NOT be sick.