What you see above is only a mockup, but the first production vest should be ready by the end of 2017. And no, the first test won't involve humans. The Orion mission should fly with an AstroRad strapped to a torso dummy to see how much radiation it absorbs, with an unprotected dummy serving as a reference point.

If successful, the vest could be crucial to both Mars missions and any other trip into deep space. At the moment, specially sheltered areas are the best defense against gamma rays. AstroRad wouldn't necessarily give crews the freedom to operate as usual during solar storms and other gamma ray events, but they might not have to beat a hasty retreat in the right circumstances.