Three “Environmental Classes” of diesel fuel were introduced in Sweden:
- Environmental Class 1 (EC1) of maximum sulfur content of 10 ppm (wt.)
- Environmental Class 2 (EC2) of maximum sulfur content of 50 ppm (wt.)
- Environmental Class 3 (EC3), equivalent to the European EN 590 diesel
The EC1 grade has been supported by tax incentives compared to the EN 590 grade. Due to this tax policy, the EC1 grade has reached nearly full market penetration in Sweden. At the time of its introduction, back in 1991, the EC1 diesel was the first ultra low sulfur diesel fuel in the world.