The "Helly Hansen SeaAir" was introduced to the norwegian offshore worker a couple of years ago. It´s got some interesting features like, a mouthpiece connected to a breathing lung, splash hood and an integrated emergency beacon. I never tried it so I´m not able to make any comments. The suit seems to be purpose-built though.
With the splash hood pulled down.
Not my pictures, it´s taken from this article.
tu.no - Nye redningsdrakter i høyt tempo - Teknisk Ukeblad
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