As a supercarrier of the United States Navy and the lead ship of its class, the USS Nimitz is one of the largest warships in the world. It was laid down by Newport News Shipbuilding in 1968 and was named after World War II Pacific fleet commander Chester W. Nimitz. Throughout its activity, the ship received numerous awards, including the National Defense Service Medal, the Meritorious Unit Commendation, and the Global War on Terrorism Expeditionary Medal. Asbestos is present aboard the USS Nimitz in tremendous amounts, particularly in insulation, which now places those who served on the ship at high risk of developing a serious disease as a result of exposure. For this reason, it is strongly advised that military personnel who were present on the USS Nimitz undergo regular medical examination, as diseases caused by asbestos exposure take between 20 and 50 years to develop. Currently, the ship is in active service as the oldest aircraft carrier in the world.