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Vehicle and Engine Certification

Permeation Families: Family Naming Conventions

To determine Positions 1-4 of your Permeation Family name, see:

Use the applicable table below to create Positions 5-12:

Small Spark-Ignition, Large Spark-Ignition, Marine Spark-Ignition or Portable Fuel Containers

Location in Family Name Code/Value Description or Instructions
Position 5 P Industry sector code for all "Permeation Families"
Positions 6-9 TANK Fuel tank permeation
PFCS Portable fuel container permeation
CAPS Fuel cap permeation
LINE Fuel line permeation
MDRN Marine diurnal
LDRN Large SI diurnal
VSSL Vessel
HHEQ Handheld equipment
NHEQ Nonhandheld equipment
Positions 10-12 *** Enter any combination of valid characters in order to provide a unique identification for your family name.

Off-Highway Motorcycles, All-Terrain Vehicles, Utility Vehicles

Location in Family Name Code/Value Description or Instructions
Position 5 P Industry sector code for all "Permeation Families"
Positions 6-10 METAL Metal fuel tank
Position 6 P Plastic
F Fiberglass
Position 7 0 No barrier
1 Inherently low/zero permeation material
2 Continuous multi-layer with permeation barrier
3 Non-continuous barrier platelets
4 Barrier surface treatment (e.g., fluorination, sulfonation)
5 Other permeation control technology
Positions 8-9 XX For tanks with no barrier (values of 0, 1, 4, 5 for Position 7 Control Strategy) :
  • Enter the least nominal tank wall thickness, rounded to the nearest millimeter (mm)
XX For tanks with a barrier (values of 2 or 3 for Position 7 Control Strategy) :
  • Enter the least weight percentage (wt.%) of barrier material within the group of fuel tanks
Position 10 B Blow-molded tank
T Thermoformed tank
R Rotational molded tank
J Injection molded tank
O Other production method
Positions 11-12 ** Enter any combination of valid characters in order to provide a unique identification for your family name.

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