Information about Family Naming Conventions for Vehicles and Engines

On this page:

• Overview
• Step 1. Find the applicable model year code
• Step 2: Determine your manufacturer code
• Step 3: Find your industry sector

Overview

A family is the basic unit that EPA uses to identify a group of vehicles or engines for certification and compliance purposes.

• Engine family;
• Test group;
• Vehicle family;
• Durability group; and
• Evaporative and/or permeation and/or refueling family.

A manufacturer should apply for new certificates and pay the appropriate certification fees for each family name that it intends to produce for sale in the United States.

A family name is a 12 character code that identifies all parts of that particular engine.

The typical naming convention is shown below, although some sectors have a slight variation.

* For dual or variable displacement families, enter the maximum displacement. If the displacement is given in liters, the decimal point count as a digit. In all cases, the displacement will be read in liters if a decimal point is included and it will be read in cubic inches or cubic centimeters if there is no decimal point.

Follow these steps to create your family name:

STEP 1: Find the applicable model year code.

From the table below, find the code for Position 1 of your family name.

STEP 2: Determine your manufacturer code.

This code is the 3-character, alpha-numeric code that EPA assigns to each company. Use this code for Positions 2-4 of your family name.

STEP 3: Find your industry sector.

Click on your industry sector to view specific instructions for determining Positions 5-12 of your family name.

Searchable/Sortable Table Instructions

The table default is to show all table entries.

For example, to change the number of entries shown in the image below, you would click the drop-down arrow next to "All."

The column with the blue arrow indicates which column your table is sorted by.
For example, if you saw the image below, the table would be sorted in ascending order on the "Technology Type" column.

To change which column your table is sorted by, click an arrow in another column.
For example, if you wanted to sort by descending order on the "Applicable for" column in the image below, you would click the down arrow.

You can filter the table using the Search box. Start typing in the search box and your table will automatically display only rows that contain what you entered in the search box.

table-sort-options.png

* This also includes heavy-duty highway vehicles at or below 14,000 pounds GVWR that are not tested on a chassis-dynamometer for certification under 40 CFR Part 1037 (i.e., certified to the requirements and standards of §1037.105, per §1037.104(f)).