Underwater surveys are performed using magnetic, electromagnetic, acoustic and seismic methods. The sensors are placed as close to the water bed as required to achieve the desired detection and performance (target). Whichever device is used for taking the measurements and for navigation, it must be ensured that there is no risk of contact with explosive ordnance. Furthermore, operatives must ensure compliance with general safety measures required for waterborne operations, such as the provision of life-saving equipment on watercraft. Please also refer to the accident prevention regulation “Diving operations” (BGV C23).
Clearance of suspected ordnance under water is performed by divers, who must be certified according to § 20 of the German Explosives Act (SprengG). In current flowing waters, explosive ordnance clearance can only be performed safely by divers up to a current of 0.6 m/sec. If the speed of the current is greater than 0.6 m/sec, it is necessary to deploy current flow protection technology, such as antimagnetic protective tubes or flow protection shields.
All procedures must comply with the provisions of the BGI 833 safety guidelines.