Calculating Capacity and the Capacity Plate
The Capacity Plate
A boat operator should never take a boat on the water with too many people or too much gear on board. Boats loaded beyond their capacity will swamp or capsize more easily and will be more difficult to control.
- Look for a capacity plate near the operator's position or on the transom of the boat. This plate indicates the maximum weight capacity and/or the maximum number of people that the boat can carry safely in good weather.
- You should not exceed either the stated maximum weight capacity or the maximum number of people.
- Maximum weight is the combined weight of passengers, gear, and motors.
- In many states, it is a violation to exceed capacity.
- Federal law requires single-hull boats less than 20 feet in length to have a capacity plate. (However, PWC and sailboat manufacturers are not required to attach a capacity plate.) Always follow the recommended capacity found in the owner's manual and on the manufacturer's warning decal. Never exceed these capacity recommendations.
Example of a Capacity Plate
Although federal law requires capacity plates only on boats less than 20 feet in length, the National Marine Manufacturers Association (NMMA) requires a capacity plate on all boats less than 26 feet in order to be certified by NMMA.
Calculating Your Boat’s Capacity
On boats less than 20 feet in length with no capacity plate, use the following rule of thumb to calculate the number of persons (weighing 150 lbs. each, on average) the vessel can carry safely in good weather conditions.
Number of people = vessel length (ft.) x vessel width (ft.) ÷ 15
For example, for a vessel 18 feet long by 6 feet wide, the number of persons is 18 times 6 (or 108) divided by 15, which equals seven 150-lb. persons (or a total person weight of 7 x 150, or 1050 lbs.).