Unexploded ordnance

Unexploded ordnance (or UXOs) are explosive weapons (bombs, shells, grenades, etc.) that did not explode when they were employed, and still pose a risk of detonation, even after the battle in which they were used. Unexploded ordnance from as far back as World War I still pose a hazard in parts of the world. Today cluster bombs are especially problematic in this regard.

In the London Blitz, any unexploded bomb was referred to as a UXB. In artillery, especially on practice ranges, an unexploded shell is referred to as a blind.

Besides the explosive hazard, buried UXO also entails the risk of environmental contamination. In some heavily used military training areas, munitions-related chemicals such as explosives and perchlorate (a component of pyrotechnics and rocket fuel) can enter soil and groundwater. A prominent example exists at the Massachusetts Military Reservation (MMR) on Cape Cod, Massachusetts (USA), where decades of artillery training has contaminated the only drinking water for thousands of surrounding residents. An expensive UXO recovery effort is underway there.

See also

• land mine
• bomb disposal
• weapons decommissioning