Temperatures (both high and low) and wide fluctuations in humidity can be hazardous to certain goods. High ambient air temperatures and fluctuations affected by direct sunshine in vans, sheds,etc., or close proximity to heating systems and boilers can occur. A United States Government study of truck containers stored in the Arizona Desert indicated that inside air tempertures can be in excess of 150 F (65 C) for a short period of time, and in excess of 130 F (54 C) for up to 7 hours per day. Low temperatures may occur due to ambient air or transportation wind. Solar radiation or exposure to light (usually the ultra-violet region) can also be hazardous to certain goods by causing chemical property changes to sensitive parts. Radiation can also fade artwork printed on cartons, and weaken hydrogen bonds in paperboard cartons. It can also wrap wood shipping containers.