Nuclear Submarines and Aircraft Carriers

Nuclear submarines and aircraft carriers are powered by onboard nuclear reactors.

      Heat from the nuclear reaction makes the steam needed to power the submarine.

      When a nuclear vessel is taken out of service, its radioactive parts are disposed of and monitored.

About Nuclear Submarines and Aircraft Carriers

In 1954, the U.S. Navy launched the first submarine that used radioactive material as a power source. Before
then, submarines used diesel engines and had to go into port for fuel. Nuclear power provided submarines with
about twenty years of power without having to stop for fuel. Food supplies became the only limit on a nuclear
submarine's time at sea. Since then, similar technologies have been developed to power aircraft carriers.

Nuclear submarines and aircraft carriers are powered by onboard nuclear reactors. Atoms in the nuclear
reactor split, releasing energy as heat. This heat is used to create high-pressured steam. The steam turns
propulsion turbines that provide the power to turn the propeller. Additional turbines also make electricity for the
ship. As the steam cools and condenses back into water, the water is routed back through pipes and the
process starts again.

The nuclear reactor compartment is shielded to protect the crew from the radiation the reactor releases.
Reactor engineers wear radiation monitors that are checked regularly. They follow strict safety procedures,
work in shifts and carefully plan the work to limit their time in the reactor compartment.

Rules and Guidance


The Navy operates all nuclear submarines and aircraft carriers. The Navy is in charge of properly disposing of
nuclear vessels that are no longer used. The nuclear fuel is removed from the reactor and sent to the Naval
Reactors Facility in Idaho for processing. The nuclear reactor compartments are cut out, carefully sealed and
taken to an approved disposal site. After the vessel's hazardous materials are properly removed and disposed
of, the ships are stored at Puget Sound  Naval Shipyard in Bremerton, Washington. They are eventually cut up
and the various metals are recycled.

When submarine and aircraft carrier nuclear reactors are no longer being  used, the compartments are shipped
to the final disposal site on barges. During shipment, the Coast Guard or the U.S. Navy will provide an escort
vessel to ensure the security of the barge. The Coast Guard may periodically inspect the barges.


DOE disposes of some types of contaminated reactor parts from nuclear vessels at the Hanford facility in
Washington State. These contaminated reactor parts are stored in specially designed waste storage cells.
  United States Environmental Protection Agency | Office of Radiation and Indoor Air (6608T) | EPA 402-F-14-037 | August 2014 | p. 1


The Navy must comply with DOT regulations when shipping the reactor compartments. Radiation levels must
not exceed DOT limits. These limits are in place to protect workers, the public and the environment while
shipping and managing the reactor compartments and components.


EPA's Superfund is the federal government's hazardous waste cleanup program. Hanford, Washington, where
contaminated nuclear vessel parts are housed, is a Superfund site. EPA,  DOE, and the State of Washington
developed an action plan addressing Superfund and Resource Conservation and Recovery Act (RCRA) issues
at the Hanford site.

Oregon's Department of Energy works with the U.S. Navy to ensure the safe passage of barges carrying
nuclear waste. Washington State's Department of Ecology, Nuclear Waste Program works to oversee all
Hanford nuclear waste activities.

What you can do

Radiation safeguards for nuclear vessels are extremely thorough and strict. There is no reason civilians should
ever encounter any exposure risk from nuclear submarines or the disposal sites that store the dismantled
reactor compartments.
Respect Safety Zones: Safety zones are often established around contaminated sites. These zones limit
public access to hazardous materials that may cause adverse health effects. The people working  inside of the
safety zone are trained professionals who are educated in safety procedures and potential hazards.

Where to  learn more

You can learn more about nuclear submarines and aircraft carries by visiting the resources available on the
following webpage:
  United States Environmental Protection Agency | Office of Radiation and Indoor Air (6608T) | EPA 402-F-14-037 | August 2014 | p. 2