In fact, there are several different methods and governmental agencies worldwide that rate the capacity of a life raft based on the following criteria: usable floor area, inflated buoyancy, their concept of how long someone might be in the raft before rescue, and how big that agency thinks users might be on average. In addition, consideration needs to be put into how you find yourself to be there, i.e. from a sinking vessel or a ditched aircraft. In general, a life raft's capacity is defined by its total size in floor area and inflated buoyancy. How many "people" that translates into depends upon your usage; your typical passengers, your boating location and, most importantly, how long you might be in it before rescue.
A raft that might safely support 6 or 8 people in an emergency for 24 hours will seem a lot smaller for a transoceanic passage where rescue might be weeks in coming. The longer amount of time that is, and the bigger your passengers, the smaller the raft will seem.
Additionally, a life raft that is rated as a 6-person life raft by ISAF standards may be considered an 8-person life raft by FAA/TSO standards. It all depends on who is asking the question. See a detailed description of capacity specifications from different organizations below. Each specification has been established by various governmental personnel's ideas of how long you might be in the raft until rescue.
At Switlik, we believe that, as a responsible boater or aviator, it is your responsibility to determine the appropriate size needs of your emergency flotation equipment, not some bureaucrat or marketer.
So we provide you with the total floor area and the total inflated buoyancy of our life rafts and let you determine its "capacity" based upon where you will go, who you usually have on board and how long you might go missing.
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