Ships of the desert. Camels were domesticated more than 3,000 years ago, and to this day, humans depend on them for transport across arid environments. They can easily carry an extra 200 pounds (90 kilograms) while walking 20 miles (32 kilometers) a day in the harsh desert.
Definition - What does Permissible Exposure Limit (PEL) mean? Permissible exposure limit (PEL) is the legal limit in the U.S. for maximum concentration of any chemical in the air to which a worker may be exposed continuously for eight hours without any danger to health and safety. PEL is established by the Occupational Safety and Health Administration (OSHA).
The annual occupational whole body dose limit (DDE) is 5000 millirem. The annual eye dose limit (LDE) is 15000 millirem. The annual shallow dose limit (SDE) is 50000 millirem. For information on the dose limits and definitions of terms used in this report, the client is referred to Part 20 of Title 10 of the Code of Federal Regulations (10CFR20).