AK SB253

Limits sulfur content in marine fuel to 0.1% by weight within the North American Emission Control Area and 0.5% by weight outside the emission control area for vessels operating in Alaska's coastal waters

Exempts vessels during ocean-going voyages that pass through Alaska waters without stopping at two or more ports, as well as vessels making unplanned stops due to emergencies, distress, or rescue operations

Exempts vessels owned or operated by the United States or foreign governments from all requirements

Authorizes the Department of Environmental Conservation to grant exemptions for vessels using alternative technologies that achieve equivalent or lower total sulfur output than 0.1% sulfur fuel

Excludes alternative fuels including natural gas, propane, ethanol, methanol, hydrogen, electricity, and fuel cells from the definition of regulated marine fuel