"None of the vessels used as floating armouries has been purpose-built as an armoury; instead, they are adapted craft. As a result, vessels may not have safe and secure storage for arms and ammunition," the report said.
Andrew Smith, a spokesman for the UK-based organisation Campaign Against Arms Trade, said: "Unfortunately, it is characteristic of an illegitimate and immoral arms industry that receives very little scrutiny and oversight ... Putting more weapons into unstable environments can bring unforeseen and deadly consequences."
MNG Maritime, a London-based company, has a floating armoury based off Fujairah in the Gulf of Oman and another due to be deployed in the Red Sea next year.
Mark Gray, MNG's director, said he would welcome more transparency in the industry, and backed the idea of a new international safety standard. "Overall, the [Omega] report was completely fair. Companies must stop exploiting countries with 'black-classification', which means they can get away with the bar set very, very low for safety," he said.
"It would be very sensible to put this power in the hands of the International Maritime Organisation."
- Independent