The military conducted live-fire training and combat operations at sea for centuries, and some Department of Defense operational ranges impacted the sea and other water bodies. Following international practices at the time, the U.S. military and militaries of other nations disposed of excess, obsolete and unserviceable munitions at sea prior to 1970. Because of this, munitions may be encountered anywhere, not just in charted hazard areas.

While diving or snorkeling, you could encounter munitions, especially if you are exploring in an area that was part of a former range or a wartime wreck. Munitions encountered should be considered dangerous.

Help protect yourself and other divers or snorkelers, and make underwater adventures safe from explosive hazards by following the 3Rs of Explosives Safety and warning those with you to do the same: