Lifejackets for rescue personnel should meet many requirements, and it is rarely that one lifejacket cover all. In surface operations, for example river rescue work, it is often recommended to use a PFD with fixed buoyancy around 70N with basic functionality as quick release D-ring on the back. Rescue crew in e.g. fire service often prefers such a PFD, but if the mission is to dive down to an accident at a depth of up to 10 meters, they prefer to use an inflatable ascent vest with about 100N buoyancy. This does not prevent you from diving and can be inflated and serve as support when bringing a person to the surface. In NSSR (Norwegian Society for Sea Rescue), a 275N lifejacket is used as safety equipment in daily operations. In a sharp rescue missions a PFD with fixed foam buoyancy is used.