US Navy (USN) Damage Controlman Second Class (DC2) Ronnie Longoria uses a Portable Exothermic Cutting Unit (PECU) during a damage control training exercise aboard the USN Aircraft Carrier, USS NIMITZ (CVN 68). The PECU provides for more rapid access into areas of the ship where normal access is impaired during firefighting operations. It is also used to drain accumulated firefighting water from areas of the ship where the effects of the accumulated water will impair the ship's stability