Boatswain's Mate 3rd Class Constance Grant, left, assists Operations Specialist 3rd Class Howard Tokheim in donning his MCU-2P gas mask during a chemical, biological, and radiological training exercise aboard the aircraft carrier USS George H.W. Bush (CVN 77). George H.W. Bush is conducting training and carrier qualifications in the Atlantic Ocean. (U.S. Navy photo by Mass Communication Specialist 2nd Class Tony D. Curtis)