The music is currently used as a second line of defence and is broadcast when initial calls from armed security guards on board fail to deter the pirates. The speakers can be aimed solely at the pirates so as not to disturb the crew. “They’re so effective the ship’s security rarely needs to resort to firing guns," — says Rachel.
Steven Jones, of the Security Association for the Maritime Industry, said the US police and military were the first to use music to quell rioters.
Security industry is well aware of the power of music — and is cautious not to exceed humane limits. Justin Bieber, for example, is not used, because officials are wary of violating Geneva Conventions."
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