Underwriters Laboratories Announces Position on Use of B5 Biodiesel Blends

Underwriters Laboratories Inc. (UL) has announced that products intended to use biodiesel blends up to B5 that are compliant with applicable ASTM International fuel standards will not require special investigation by UL. This is consistent with ASTM standards for heating oil and diesel fuel, which were recently updated to indicate that B5 blends may be considered the same as the conventional petroleum fuels under their scope.

In anticipation of the changes to the ASTM fuel standards, UL initiated a technical review of biodiesel fuel and technologies working closely with US Department of Energy, National Renewable Energy Laboratory, Brookhaven National Laboratory, Oak Ridge National Laboratory, and the National Biodiesel Board. UL also conducted performance testing of heating equipment using B5.

The findings indicated no adverse safety effects. It is acknowledged however that introduction of biodiesel may potentially affect fuel quality, mobilize contaminants in the fuel system, or increase the potential for microbial contamination. These performance issues are outside of the scope of UL standards and certification. Manufacturer instructions for use and maintenance of equipment should always be followed.

Use of biodiesel at levels above 5% may have a significant effect on materials, performance or combustion of some equipment. UL is in the process of finalizing product safety requirements for equipment specified for use with biodiesel (B100) and biodiesel blends up to B20.

UL is an independent, not-for-profit product safety certification organization. We remain committed to promoting safe living and working environments through the development of effective safety standards, product investigations and ongoing safety-based audits of products that bear the UL Mark. UL remains independent in this mission and does not endorse, recommend or favor one product over another.