Abstract: An impact sensor has a hollow container with a spring extending therethrough. A liquid is present in the cavity. The spring biases opposing valve balls to a closed position, preventing dye that is located exterior of the cavity from entering the cavity. When a force applied to the sensor exceeds a first predetermined value, the spring is compressed or displaced, allowing at least one of the valve balls to move from the closed position to an open position, thereby allowing the dye at the moving valve ball to pass into the cavity, mixing with the liquid and providing a visual indication of the exceeded force upon the sensor.