Guidance for Biodiesel Producers and
   Biodiesel Blenders/Users
United States
Environmental Protection

                   Guidance for Biodiesel  Producers  and
                            Biodiesel Blenders/Users
                              Transportation and Regional Programs Division
                                 Office of Transportation and Air Quality
                                 U.S. Environmental Protection Agency

                   This guidance does not necessarily represent final EPA decisions or
                   positions. It is intended to present technical analysis of issues using data
                   that are currently available. The purpose in the release of such guidance is
                   to facilitate the exchange of technical information and to inform the public of
                   technical developments.
United States                                          EPA420-B-07-019
Environmental Protection                                   .,    ,   .,
Agency                                              November 2007


The purpose of this document is to explain and clarify EPA's regulatory
requirements for biodiesel producers and biodiesel blenders/users.  While the
term biodiesel generally has a broad interpretation, as used in this guidance
document, its meaning  is directed specifically to biodiesel-ester.


Use of renewable fuels, such as ethanol and biodiesel, in motor vehicle fuels has
been growing rapidly for a variety of reasons. Biodiesel usage has been
increasing particularly rapidly. This widespread increase in biodiesel usage has
highlighted a need to promote adherence to the primary industry standard for
biodiesel (B100 blendstock used to produce biodiesel blends), ASTM
International (ASTM) D 6751, and consider new ASTM standards for blends of
biodiesel and conventional petroleum-based diesel. EPA is also currently
coordinating significant additional testing to resolve issues related to the effect of
biodiesel on vehicle emissions performance.

Biodiesel is a fuel made from plant or animal feedstocks, and may be used in
conventional diesel engines.  Biodiesel is comprised of specific chemical
components defined by ASTM as "mono-alkyi esters of long chain fatty acids
derived from vegetable oils or animal fats."  In the United States, most biodiesel
is made from soybean oil. However, canola oil, sunflower oil, recycled cooking
oils, palm oil, animal fats, and other oils are also used as feedstocks.

Biodiesel is typically manufactured through a process called "trans-esterification."
This process uses an industrial alcohol (typically methanol, sometimes ethanol)
and a catalyst (sodium methylate, can be sodium hydroxide) to convert the base
plant oil or animal fat into a fatty-acid mono-alkyl ester fuel (biodiesel), with
glycerin as a byproduct. Biodiesel in its pure form is known as B100, but it can
be blended with conventional diesel fuel.  The most common blends are B5 (5
percent biodiesel and 95 percent conventional diesel) and B20 (20 percent
biodiesel and 80 percent conventional diesel).

Biodiesel is registered with the U.S. Environmental Protection Agency (EPA) as a
motor vehicle diesel fuel and motor vehicle diesel fuel additive. It is registered for
use at any blend level up to B100 in highway diesel vehicles.

Biodiesel, as discussed in this document, does not include renewable diesel.
Renewable diesel is a non-ester based diesel blend derived from non-petroleum
resources, such as plant oil or animal fats or wastes.  Because renewable diesel
is processed in a refinery along with petroleum stocks, it  becomes

indistinguishable from petroleum diesel, and does not need to be blended
downstream of the refinery.

Neat vegetable oils and recycled greases (also called waste cooking oil or yellow
grease) that have not been processed into mono-alkyl esters are not biodiesel.
These raw oils, used as fuel extenders or fuel substitutes, are not registered with
EPA and are not legal to use as a motor vehicle fuel. Furthermore, cooking oil is
physically and chemically different than  diesel fuel and its use in conventional
engines will generally cause negative effects on emissions and engine durability.

Because of the potential for increased emissions, it is considered unlawful
tampering to convert a vehicle designed for diesel fuel to operate on waste oil
without EPA certification. To date, EPA has not certified any conversions for
waste oils. Even with EPA certification,  conversions may violate the terms  of the
vehicle warranty.  For more information  on the certification process, please visit
EPA's Web site at: www.epa.aov/otag/cert/dearmfr/cisd0602.pdf (22 pp, 152 K,
About PDF)

EPA Requirements for Biodiesel Producers under 40 CFR Part 79 and Part

Section 211  of the Clean Air Act provides EPA with the authority to regulate fuels
and fuel additives in order to obtain information about emissions and health
effects related to fuels and their additives, and where appropriate to reduce the
risk to public health from exposure to their emissions.  In part, regulations
implementing this authority are codified  in Part 79 of the Code of Federal
Regulations  (40 CFR Part 79), which requires that each manufacturer or importer
of motor vehicle gasoline, motor vehicle diesel fuel, and their additives, have their
product registered by EPA prior to its introduction into commerce. Registration
involves providing a chemical description of the product and certain technical,
marketing and health-effects information. This allows EPA to identify the likely
combustion and evaporative emissions.  In many cases,  health-effects testing is
required for a product to maintain its registration  or before a new product can be
registered. EPA uses this information to identify  products whose emissions may
pose an unreasonable risk to public health, warranting further investigation
and/or regulation.

Producers of biodiesel for highway use are manufacturers of motor vehicle fuel or
fuel additive.  As part of EPA's registration process for fuel manufacturers,
biodiesel producers must complete and  submit EPA registration form 3520-12
(Fuel Manufacturer Notification for Motor Vehicle Fuel, available at
http://www.epa.qov/otaq/reqs/fuels/ffarsfrms.htm), and also provide the following

   1.  The feedstocks used to produce  biodiesel.
   2.  A description of the manufacturing process used to produce biodiesel.

   3.  Emissions and health effects testing on the manufacturer's biodiesel, or
      alternatively proof of registration with the National Biodiesel Board (NBB)
      showing access to the Tier 1 and Tier 2 emissions and health effects
      testing data.
   4.  Test results from a representative sample of the manufacturer's biodiesel
      demonstrating compliance with the parameters specified in ASTM D 6751.

Since emissions and health effects testing for biodiesel is very expensive,
biodiesel producers normally arrange for access to "group data" on the testing of
biodiesel which is representative of all products in that group. NBB has provided
EPA with the required group data on biodiesel that met the nationally accepted
biodiesel standard at the time of testing, which was 1998. This standard has
since  been adopted as ASTM D 6751, and continues to undergo refinements.
Thus,  a biodiesel producer may meet EPA's emissions and health effects testing
requirement for biodiesel by reaching an agreement with NBB for access to
NBB's registration data, and making a certification to EPA that the producer has
notified  NBB of the use of NBB's data and reimbursed NBB for the use of their
data.  Any biodiesel producer who does not have access to NBB's data must
provide EPA with its own emissions and health effects test data as part of the
registration process.

In addition to registering with EPA under 40 CFR Part 79, biodiesel producers
are also required to register under 40 CFR Part 80 as a refiner. This applies to
both highway and nonroad biodiesel.  Under 40 CFR Part 80, diesel fuel
producers must complete and submit EPA registration forms 3520-20A (Fuels
Programs Company/Entity Registration) and 3520-20B1 (Diesel Programs
Facility Registration). Both of these forms are available at

Highway and nonroad biodiesel producers must also comply with all of EPA's
regulatory requirements for diesel fuel producers  in 40 CFR Part 80, Subpart  I.
The primary standard for diesel fuel producers in  Subpart I is the 15 ppm sulfur
standard, which will be phasing in for all diesel fuel from now through 2014.
Although biodiesel typically contains less than 15 ppm sulfur, biodiesel producers
are still required to test each of their biodiesel batches for sulfur and
appropriately designate their product as required  by Subpart I. Subpart I also
contains diesel fuel standards for minimum cetane index (40), or a maximum
aromatics content (35 volume percent), which biodiesel typically meets. Lastly,
Subpart I contains reporting and recordkeeping requirements for diesel fuel

EPA Guidance for Biodiesel Blenders/Users

Although the Part 79 registration is for biodiesel use at any blend level up to
B100  in highway  diesel vehicles, ASTM D 6751 points out that a considerable
amount of experience exists with blends containing 20 percent biodiesel and 80

percent conventional diesel (B20).  Thus, ASTM D 6751  recommends that
biodiesel blends containing more than 20 percent biodiesel should be evaluated
on a case-by-case basis. ASTM D 6751 also recommends that biodiesel users
consult the equipment manufacturer owner's manual regarding the suitability of
using biodiesel or biodiesel blends in a particular engine or application. Many
engine manufacturers currently limit warranty coverage to diesel fuel containing
no more than 5 percent biodiesel.

Consumers should be careful only to buy biodiesel from  a reputable dealer.
Improperly processed biodiesel may contain unreacted or partially reacted oils or
fats (measured by the total glycerin), which can cause the fuel to gel at higher
than expected temperatures.  ASTM D 6751 specifies maximum allowable
concentrations of free glycerin and total glycerin.  Also, consumers should be
careful that they are not inadvertently purchasing straight vegetable oil instead of
biodiesel.  One method  of ensuring quality biodiesel is to buy from producers or
marketers that are certified in the voluntary national  biodiesel accreditation BQ
9000 program (see for details).

Requirements for handling and using biodiesel may  differ from requirements for
petroleum-based diesel. For example, biodiesel can gel at low temperatures and
may require special handling in cold climates during winter.  Other possible
problems that may be caused by B100 use include degradation of some fuel
lines and gaskets (e.g. those made from nitrile and natural rubber) and reduced
power or fuel  economy. Consumers should check with their vehicle
manufacturers for recommendations about biodiesel use or consult the
information available on the NBB web site at under 'Engine Manufacturers'.

Engine manufacturers have expressed concern about degradation of biodiesel
due to long storage times, which may cause biodiesel to exceed the limits in
ASTM D 6751 for acid number, viscosity or sediment. For example, NBB
recommends  that B100 be stored for no more than 6 months before usage. The
Department of Energy document "Biodiesel Handling and Use Guidelines"
(available at contains
a detailed discussion on the stability of B100 and B20 and is a good source of
information on biodiesel in general.

Current Activities Regarding Biodiesel

Emissions Performance

Having an accurate assessment of biodiesel effects  on diesel engine emissions
is critical to state, regional and national  organizations for making informed
decisions regarding biodiesel use.  EPA's 2002 review of then available test data
entitled "A Comprehensive Analysis of Biodiesel Impacts on Exhaust Emissions"
concluded that biodiesel improves HC, CO and particulate emissions while

slightly increasing NOx.  However, the magnitude of biodiesel NOx impact still
remains controversial. EPA has recently shown experimentally that this impact is
proportional to test cycle load. Using this information and working in cooperation
with the stakeholders, EPA has developed a proposal for a Collaborative
Biodiesel Emission Test  Program to address the NOx issue. The funding for this
test program is currently  uncertain.  However,  we continue to believe that a well-
designed study such as this is necessary to accurately determine the effect of
biodiesel on emissions.  In addition, EPA is currently updating the 2002 biodiesel
study using test data which have become available in recent years.

Standards Harmonization

EPA is also working with several standard-setting organizations,  both nationally
and internationally, and other government organizations in a general effort to
harmonize standards for biofuels produced from a variety of feedstocks and
blended in petroleum-based fuels at various concentrations.  EPA's regulations
codifying the Renewable Fuel Standard Program established in the Energy
Policy Act of 2005 (EPAct) were recently finalized in 40 CFR Part 80, Subpart K,
and provide significant flexibility for biofuels producers, refiners and importers to
properly account for the large volumes of renewable fuels that  must be blended
into gasoline or diesel fuel under EPAct. Since EPAct does not mandate where
biofuels must be produced or blended into gasoline or diesel fuel, EPA
encourages other standard-setting organizations, particularly state governments,
to allow biofuels producers and biofuels blenders the flexibility  to decide where
biofuels can be most economically produced and blended into  gasoline or diesel
fuel.  EPA is promoting standards that will result in nationally accepted,
consistent, biodiesel quality  levels and blend rates.

EPA is also participating in several ongoing ASTM activities regarding biodiesel
quality and standards. ASTM recently added a stability specification to ASTM D
6751 and expanded the applicability of ASTM  D 6751  to all diesel fuels (ASTM D
6751 was previously applicable to just highway diesel fuel). EPA's renewable
fuels program regulations, recently finalized in 40 CFR Part 80, Subpart K,
require biodiesel producers to meet all specifications in the most recent version
of the standard (ASTM D 6751-07) for biodiesel to be considered a renewable
fuel, and included in compliance calculations under Subpart K  (see 40 CFR
80.1101 (h)(3) and 80.1115(b)). ASTM is also considering whether to expand
their standard for petroleum-based diesel fuel  (ASTM D 975) to include diesel
blends that contain up to 5 volume percent biodiesel, and is developing a
standard for B6 to B20.

Enforcement Activities

EPA also plans to increase enforcement efforts to ensure that biodiesel
producers are complying with EPA's standards, in  particular ensuring that all
biodiesel meets ASTM D 6751.  Section 211 (a) of the Clean Air Act gives the

Administrator of the EPA regulatory authority to "...designate any fuel or fuel
additive... and... no manufacturer or processor of any such fuel or fuel additive
may sell, offer for sale, or introduce into commerce such fuel or additive unless
the Administrator has registered such fuel or additive...." This is codified in
EPA's regulations at 40 CFR 79.4(a)(1), which state that "no manufacturer of fuel
designated under this part shall  ... sell, offer for sale, or introduce into commerce
such fuel unless the Administrator has registered such fuel."

ASTM D 6751 was first published in 2002 (ASTM D 6751-02). Since then it has
been periodically revised and updated. EPA's routine practice has been to
register biodiesel that meets the version of ASTM D 6751 in effect at the time of
registration. Because most biodiesel has been registered with EPA since 2002,
EPA expects that most biodiesel will meet either ASTM D 6751-02, or later
versions of ASTM D 6751. For biodiesel registered since 2002, any biodiesel
that does not meet the version of ASTM D 6751 in effect at the time of
registration will be considered an unregistered fuel  subject to the penalty
provisions in 40 CFR 79.8 (civil penalties of up to $32,500 per day per violation).
Biodiesel registered prior to 2002 must meet the ASTM D 6751 specifications
contained in its registration application, which are generally equivalent to ASTM
D 6751-02.  For biodiesel registered prior to 2002, any biodiesel that does not
meet the ASTM D 6751 specifications contained in its registration application will
be considered an unregistered fuel subject to the penalty provisions in 40 CFR
79.8 (civil penalties of up to $32,500 per day per violation).

In addition to the provisions covering violations under 40 CFR Part 79, violations
of EPA's diesel fuel standards in 40 CFR Part 80, Subpart I are covered in 40
CFR 80.610 through 80.615. EPA regulations at 40 CFR 80.4 also provide
authority to EPA inspectors, who present appropriate credentials, to enter the
premises of any fuel manufacturer, importer, carrier or distributor and make
inspections, take samples, obtain information and records, and conduct tests to
determine compliance with all of EPA's fuels regulatory requirements in 40 CFR
Part 80. Any person who violates these regulations is  liable to the United States
for a civil penalty of up to $32,500 per day per violation (see 40 CFR 80.5).