UPRIGHT SOUNDINGS. Certains soundings in this chart are compiled from old and smaller scale surveys. Mariners are warned to navigate with extra caution when in the vicinity of the areas, see Source Classification Diagram.

PERUMAN TEGAK. Sesetengah peruman di carta ini disusun daripada pengukuran lama dan berskala lebih kecil. Amaran diberi kepada pelaut supaya berwaspada semasa memanduarah di perairan berkenaan, lihat Gambarajah Pendarjahan Sumber.