 On February 14, 2008, the CDC published a preliminary report confirming that potentially hazardous levels of formaldehyde were found in many of the travel trailers and manufactured homes provided by FEMA.In July 2008, researchers conducting a federally funded analysis reported that the toxic levels of formaldehyde were found in 42% of the trailers tested, and that they were attributable to faulty construction practices and the use of substandard building materials.As a result, FEMA modified its specifications for emergency housing, requiring that units be larger and better ventilated.