Audio gauge / Ultrasound Audio Gauge, Material Thickness Gauging Do you need a report which includes the thickness and extent of corrosion of the hull material? Our Ultrasonic gauging equipment will accurately measure the hull thickness and the extent of corrosion of metal, (steel, aluminum, and fiberglass.) This option is especially important in evaluating the seaworthiness of a steel or aluminum hull. Hull surface preparation before gauging is a must. Please note our protocol requirements for audio gauge work. The vessel must be hauled, completely power washed, and any corroded or oxidized coatings must be removed prior to audio gauging. All audio gauge equipment requires either a smooth metal surface or a smooth painted surface without the presence of any oxides which may cause inaccurate readings. When there are areas of the surface with multiple coatings the surface must be made smooth and free from pits or corroded coatings. The audio gauge contractor does not scrape paint or remove surface coatings. Appropriate staging must be in place prior to the start of work. The above are industry standard control items.