Safe Loading - Testing For Capacity

How to test a boat to determine safe load and number of passengers.

If you came to this page first, go to Safe Loading, weight capacity and person capacityand read how weight and persons capacity is determined.

The slide show depicts how a boat is tested for maximum weight capacity. These were taken at the US Coast Guard's testing facility in Solomon's Island Maryland during a training session for Coast Guard employees, the contractor that performs the testing, and the contractor that conducts visits to boat manufacturers.

Boat Testing Slideshow

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The boat is suspended over the test tank
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The boat is suspended over the test tank
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The boat is suspended over the test tank
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The boat is suspended over the test tank
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The boat is suspended over the test tank
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All openings are sealed. Here a plug is put in the fuel tank fill opening.
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The fuel tank vent is sealed to prevent water from entering the tank. Weights are added to simulate the weight of a full tank.
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Before the test the amount of weight required is calculated using the capacities on the label.
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Straps are attached so that part of the weight is supported by the crane and part by the water and so the boat does not roll over.
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Loading of weights into the boat.
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Loading of weights into the boat.
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Weights are distributed so that the boat does not heel or tilt
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Weights are distributed so that the boat does not heel or tilt
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Placement of weights is crucial. The load must be balanced so weights must be distributed through out the boat
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Placement of weights is crucial. The load must be balanced so weights must be distributed through out the boat.
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The boat is slowly lowered until water comes in or the boat floats with no water coming in.
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If water enters, weights are re-distributed until it stops. If it cannot be stopped by moving weights, the boat fails.
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Again the boat is slowly lowered until water comes in or the boat floats with no water coming in.
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The boat is slowly lowered until water comes in or the boat floats with no water coming in.
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The boat is slowly lowered until water comes in or the boat floats with no water coming in.
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The boat is slowly lowered until water comes in or the boat floats with no water coming in.
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The boat is slowly lowered until water comes in or the boat floats with no water coming in.
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If no water comes in with all the weights in the boat, it passes. If water comes in, weights are slowly removed until it passes. The remaining weight determines the maximum weight capacity.


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Revised 05/14/2023  © newboatbuilders.com 2010 All rights reserved.

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