UXO contamination concerns all types of unexploded ordnance, whether fired (artillery ammunition, mortars, rockets, missiles, torpedoes), dropped (bombs, submunitions, sea mines), thrown (grenades) or laid (landmines).
Due to the complexity of their firing mechanisms and usage conditions, a significant percentage of the ammunition used during conflicts did not detonate.
All or part of these UXOs are likely to be found on military ground, combat areas or more generally on any infrastructure of strategic interest during conflicts, such as railway areas, sea and river ports, airports, fuel depots etc.
The effects of time lead to the gradual deterioration of the components, increasing their lethal potential.