Underwater acoustic characterisation of unexploded ordnance disposal using deflagration

Stephen P Robinson; Lian Wang; Sei-Him Cheong; Paul A Lepper; Francesca Marubini; John P Hartley

doi:10.1016/j.marpolbul.2020.111646

Underwater acoustic characterisation of unexploded ordnance disposal using deflagration

Mar Pollut Bull. 2020 Nov:160:111646. doi: 10.1016/j.marpolbul.2020.111646. Epub 2020 Sep 22.

Authors

Stephen P Robinson¹, Lian Wang², Sei-Him Cheong², Paul A Lepper³, Francesca Marubini⁴, John P Hartley⁴

Affiliations

¹ National Physical Laboratory, Hampton Road, Teddington TW11 0LW, UK. Electronic address: stephen.robinson@npl.co.uk.
² National Physical Laboratory, Hampton Road, Teddington TW11 0LW, UK.
³ Loughborough University, Loughborough LE11 3TU, UK.
⁴ Hartley Anderson Ltd, Aberdeen AB11 5BE, UK.

PMID: 33181928
DOI: 10.1016/j.marpolbul.2020.111646

Abstract

The seabed off North West Europe contains much unexploded ordnance (UXO), posing a hazard to offshore developments such as windfarms. The typical removal method is through high-order detonation of a donor charge placed adjacent to the UXO. This method poses a risk of injury or death to marine mammals and other fauna from the high sound levels produced. This paper describes a controlled field experiment to compare the sound produced by high-order detonations with a low-order disposal method called deflagration, which uses a shaped charge of modest size, is less energetic, and offers reduced environmental impact from lower acoustic output. The results demonstrate a substantial reduction over high order detonation, with the peak sound pressure level and sound exposure level being more than 20 dB lower for the deflagration, and with the acoustic output depending only on the size of the shaped charge (rather than the size of the UXO).

Keywords: Acoustic; Deflagration; Noise; Pollution; UXO.

MeSH terms

Acoustics*
Europe
Sound*