This section focuses on blending B100 with petroleum diesel to make B6 to B20 blends, but the approach is similar for other blend levels such as B2 or B5. As discussed in the previous sections, the performance properties of B100 can be significantly different from those of conventional diesel. Blending biodiesel into petroleum diesel can minimize these property differences and retain some of the benefits of B100. B20 is popular because it represents a good balance of cost, emissions, cold weather performance, materials compatibility, and ability to act as a solvent. B20 is also the minimum blend level that can be used for EPAct compliance for covered fleets.