Due to the very heavy sea traffic and many large coastal settlements, the Kattegat has been designated as a Sulphur Emission Control Area as part of the Baltic Sea since 2006.
The benchmark for sulphur in fuels was recently lowered to 0.1%, to be effectuated from 1 January 2015.

Several larger areas of the Kattegat are designated as Natura 2000 and under various bird protections such as the Ramsar Convention.
The remaining larger shallow reefs are among the protections, as they are important spawning and feeding grounds for fish and marine mammals and they support a thriving but threatened biodiversity.
Protected areas includes:
Denmark
Grenen
The Bay of Aalborg, comprising a 1,774 km² (685 sq mi) shallow sea area.

Beach meadows on Læsø and the stony reefs south of the island
Anholt and the sea north of the island.

Sweden
The Nordre älv estuary north of Gothenburg.
An important spot for migratory birds and fish.

The Vrångö archipelago (Swedish: Vrångöskärgården), part of the Archipelago of Gothenburg.
An important reproduction area for seabirds and seals.

Kungsbacka Fjord.
A shallow water fjord between Gothenburg and Varberg, including important salt marshes.

Hovs Hallar
Kullaberg Nature Reserve
Due to the very heavy sea traffic and many large coastal settlements, the Kattegat has been designated as a Sulphur Emission Control Area as part of the Baltic Sea since 2006. The benchmark for sulphur in fuels was recently lowered to 0.1%, to be effectuated from 1 January 2015.
Several larger areas of the Kattegat are designated as Natura 2000 and under various bird protections such as the Ramsar Convention. The remaining larger shallow reefs are among the protections, as they are important spawning and feeding grounds for fish and marine mammals and they support a thriving but threatened biodiversity. Protected areas includes:
Denmark
Grenen
The Bay of Aalborg, comprising a 1,774 km² (685 sq mi) shallow sea area.
Beach meadows on Læsø and the stony reefs south of the island
Anholt and the sea north of the island.
Sweden
The Nordre älv estuary north of Gothenburg. An important spot for migratory birds and fish.
The Vrångö archipelago (Swedish: Vrångöskärgården), part of the Archipelago of Gothenburg. An important reproduction area for seabirds and seals.
Kungsbacka Fjord. A shallow water fjord between Gothenburg and Varberg, including important salt marshes.
Hovs Hallar
Kullaberg Nature Reserve
Kattegat