World Travel: The Fuel Challenge

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Scope:
Recent model European and USA market diesel trucks

Challenge:
Non-Euro/USA market fuel not compatible with recent model Euro/USA market diesel trucks

Summary:
Overlanders seeking to travel outside the EU and North America using recent model trucks face potentially engine and pollution control system damaging/destroying effects from developing country fuel.

Background:
Over the last 20 years, the EU and the USA & Canada have implemented a series of ever-tighter emission controls on diesel trucks. In order to meet these requirements various changes have been made in the formulation of the diesel fuel sold in those markets.

Current model diesel trucks sold in the EU and the USA/Canada require diesel fuel with extremely low levels of sulphur. This special, low sulphur diesel fuel is available in very limited areas outside of the EU/USA/Canada markets.

While the USA, Canada and Mexico generally follow the USA emissions and fuel standards, the rest of the world is aligning with EU standards, albeit at a much slower pace.


Implications:

• Current model year European and USA/Canada market trucks require 15ppm sulphur diesel fuel.
  [*]You must use a 2007 model year or older USA/Canada market truck if you are traveling outside North America.

USA & EU Diesel Fuel Requirements:

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US Diesel Fuel Grades

Historically, the quality of automotive fuels in the USA was governed by ASTM standards. Diesel fuels are covered by the ASTM D 975-04a specification, which describes seven grades of diesel:

Table 1
Diesel Fuel Grades

Heavier fuel oils Grade 5 and 6 (residual), which are used primarily for heating purposes, are described by ASTM D 396.

The Sxxx designation was first adopted in the D 975-04 edition of the standard to distinguish grades by sulfur content. The S5000 grades correspond to the “regular” sulfur grades, the previous No. 1-D and No. 2-D. S500 grades correspond to the previous “Low Sulfur” grades (D 975-03). S15 grades are commonly referred to as “Ultra-Low Sulfur” grades or ULSD.

Further ASTM specifications exist for marine diesel fuels. While some marine diesel engines use No. 2 distillate, additional ASTM specifications identify four kinds of marine distillate fuels: DMX, DMA, DMB, and DMC (see also ISO marine fuel specifications):
• DMX is a special light distillate intended mainly for use in emergency engines.
&#8226; DMA (also called marine gas oil, MGO) is a general purpose marine distillate that must be free from traces of residual fuel. DMX and DMA fuels are primarily used in Category 1 marine engines (< 5 liters per cylinder).
&#8226; DMB (marine diesel oil, MDO) is allowed to have traces of residual fuel, which can be high in sulfur. This contamination with residual fuel usually occurs in the distribution process, when using the same supply means (e.g., pipelines, supply vessels) that are used for residual fuel. DMB is produced when fuels such as DMA are brought on board the vessel in this manner. DMB is typically used for Category 2 (5-30 liters per cylinder) and Category 3 (&#8805; 30 liters per cylinder) engines.
&#8226; DMC is a grade that may contain residual fuel, and is often a residual fuel blend. It is similar to No. 4-D, and can be used in Category 2 and Category 3 marine diesel engines.
&#8226; Residual (non-distillate) fuels are designated by the prefix RM (e.g., RMA, RMB, etc.). These fuels are also identified by their nominal viscosity (e.g., RMA10, RMG35, etc.).

With the growing importance of alternative diesel fuels, specifications are also being developed for biodiesel fuels and their blends.

Sulfur Content
Since the 1990's, fuel quality has been increasingly more regulated by the US EPA under the authority of the Clean Air Act. In the context of the increasingly more stringent diesel emission standards, the most important fuel property regulated by the EPA became the sulfur content. Historically, the sulfur content in diesel fuels for highway and nonroad vehicles was limited to 0.5% (wt.) by ASTM specifications. The milestones in US environmental regulations limiting sulfur levels in diesel fuels can be summarized as follows:

Highway Diesel Fuel
&#8226; 500 ppm: Sulfur limit of 500 ppm = 0.05% (wt.) became effective in October 1993. This fuel, commonly referred to as the low sulfur diesel fuel, was introduced to facilitate sulfate particulate emission reductions, which were necessary for meeting the 1994 emission standards for heavy-duty highway engines.
&#8226; 15 ppm: Diesel fuel of maximum sulfur level of 15 ppm will be available for highway use beginning in June 2006. This fuel, referred to as the ultra low sulfur diesel (ULSD), was legislated by the EPA to enable catalyst-based emission control devices, such as diesel particulate filters and NOx adsorbers, which will be necessary for meeting the 2007-2010 emission standards for heavy-duty engines, as well as the Tier 2 light-duty standards.

Nonroad Diesel Fuels
&#8226; 500 ppm: Sulfur limit of 500 ppm becomes effective in June 2007 for nonroad, locomotive and marine fuels.
&#8226; 15 ppm: Sulfur limit of 15 ppm (ULSD) becomes effective in June 2010 for nonroad fuel, and in June 2012 for locomotive and marine fuels. The ULSD has been legislated for nonroad engines to enable advanced emission control systems for meeting the Tier 4 nonroad emission standards.

The above sulfur limits do not apply to heavy oils used in Category 2 and 3 marine diesel engines.

Source: http://www.dieselnet.com/standards/us/fuel.php


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EU Diesel Fuel

The quality of automotive fuels in the European Union is specified by standards developed by the European Standards Organization (CEN). The first set of standards for automotive fuels, ratified by CEN on 16 March 1993, became mandatory in all Member States by September 1993. Three standards cover automotive fuels quality: the EN 590 for diesel fuel, the EN 228 for gasoline, and EN 589 for automotive LPG. The standards are periodically updated to reflect changes in specifications, such as the mandatory reductions in sulfur content.

To provide options for different climates, the EN 590 standard specifies six Temperature Climate Grades of diesel fuel (Grade A...F) which differ in the CFPP value. In addition, there are five Arctic Classes of diesel fuel (Class 0...4) characterized by different properties. Each country shall detail requirements for a summer and winter grade, and may also include intermediate or regional grades as justified by national climate conditions.

Mandatory environmental fuel specifications are introduced by EU Directives.

The following are the most important steps in the evolution of EU diesel fuel specifications:
&#8226; Effective 1994.10, a maximum sulfur limit of 0.2% (wt.) was introduced for all gas oils, including diesel fuel. The minimum cetane number was 49.
&#8226; 1996.10: A maximum sulfur limit of 0.05% (wt.) = 500 ppm for diesel fuel.
&#8226; 2000.01: A maximum sulfur limit of 350 ppm and cetane number of 51 for diesel fuel.
&#8226; 2005.01: A maximum sulfur limit of 50 ppm for diesel fuel. &#8220;Sulfur-free&#8221; 10 ppm sulfur diesel fuel must be available for highway vehicles.
&#8226; 2009.01: A maximum sulfur limit of 10 ppm (&#8220;sulfur-free&#8221 for diesel fuel for highway and nonroad vehicles.

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Sample Diesel Fuel Requirements:

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Mexico Diesel

Motor vehicle fuels in Mexico are distributed exclusively by the national oil company Petrleos Mexicanos (PEMEX). Regulation NOM-086-SEMARNAT-SENER-SCFI-2005 defines two grades of diesel fuel:
&#8226; Automotive diesel (PEMEX) for use in on-road vehicles, and
&#8226; Marine and agricultural diesel.
The low sulfur automotive diesel grade (first introduced as Diesel Sin) replaced the earlier standard diesel of 5000 ppm (0.5%) sulfur.
The regulation sets automotive diesel fuel sulfur levels at 500 ppm with a scheduled reduction to 15 ppm. The following is the phase-in schedule for ultra-low sulfur (15 ppm) on-road diesel:
&#8226; February 2007&#8212;Northern frontier region that borders the USA,
&#8226; February 2009&#8212;Metropolitan regions of Guadalajara, Monterrey and the Valle de Mxico,
&#8226; September 2009&#8212;Nationwide.

Diesel fuel for marine and agricultural applications is colored and has an upper sulfur limit of 5000 ppm.

Source: http://www.dieselnet.com/standards/mx/fuel.php


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India Diesel Fuel

India has been adopting European regulations for both fuels and vehicle emissions. The Euro requirements are first introduced in Delhi and other major cities, following nationwide implementation. The evolution of diesel fuel quality is summarized in Table 1.

Table 1

Diesel Fuel Quality in India

More details on the implementation schedule of European specifications is given in the article on vehicle emission standards.

Source: http://www.dieselnet.com/standards/in/fuel.php


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Australia Diesel Fuel


The quality of automotive fuels in Australia has been regulated by a number of legal instruments, including the Fuel Quality Standards Act 2000, the Fuel Quality Standards Regulations 2001 and the Fuel Standard (Automotive Diesel) Determination 2001. The fuel quality standards are administered by the Department of the Environment and Heritage.

Two groups of standards are applicable to diesel fuels:
&#8226; Environmental Standards regulate fuel parameters that have a direct impact on the environment.
&#8226; Operability Standards address those parameters of diesel that do not have a direct impact on emissions but, if not controlled, can have adverse impacts on the efficient operation of the engine.

The environmental and operability standards for diesel fuels are summarized in the Table 1.

Table 1

Diesel Fuel Standards

Source: http://www.dieselnet.com/standards/au/fuel.php

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Fuel Availability:

The availability of various grades and sulphur levels of diesel fuel varies widely by region.

Source: http://www.unep.org/pcfv/index.asp

 

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The availability of diesel fuel also varies within countries and by where they are at in their implementation of tighter pollution standards.

 

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Diesel fuel sulphur levels are driven by pollution standards.

The two major sets of pollution standards are USA/Canada and EU. In general, countries outside the USA/Canada/Mexico are either adopting or patterning their standards after the EU.


European Standards - Passenger Cars and Light Duty Trucks

Background
European Union emission regulations for new light duty vehicles (cars and light commercial vehicles) are specified in the Directive 70/220/EEC. This basis Directive was amended a number of times, some of the most important amendments including:
• Euro 1 standards (also known as EC 93): Directives 91/441/EEC (passenger cars only) or 93/59/EEC (passenger cars and light trucks)
• Euro 2 standards (EC 96): Directives 94/12/EC or 96/69/EC
• Euro 3/4 standards (2000/2005): Directive 98/69/EC, further amendments in 2002/80/EC
• Euro 5/6 standards (2009/2014): Euro 5/6 “political” legislation

[Regulation 715/2007] of 20 June 2007; the implementing part of the regulation (which will cover test procedures, deterioration factors and, if agreed by Member States, revised PM requirements) is to be finalized by 2 July 2008

Fuels.
The 2000/2005 standards were accompanied by an introduction of more stringent fuel regulations that require minimum diesel cetane number of 51 (year 2000), maximum diesel sulfur content of 350 ppm in 2000 and 50 ppm in 2005, and maximum petrol (gasoline) sulfur content of 150 ppm in 2000 and 50 ppm in 2005. “Sulfur-free” diesel and gasoline fuels (≤ 10 ppm S) must be available from 2005, and become mandatory from 2009.

Emission Testing.
Emissions are tested over the NEDC (ECE 15 + EUDC) chassis dynamometer procedure. Effective year 2000 (Euro 3), that test procedure was modified to eliminate the 40 s engine warm-up period before the beginning of emission sampling. This modified cold start test is referred to as the New European Driving Cycle (NEDC) or as the MVEG-B test. All emissions are expressed in g/km.

The draft Euro 5/6 implementing legislation adopts a new PM mass emission measurement method (similar to the US 2007 procedure) developed by the UN/ECE Particulate Measurement Programme (PMP) and adjusts the PM mass emission limit to account for differences in results using the old and the new method. The legislation also introduces a particle number emission limit at the Euro 5/6 stage (PMP method), in addition to the mass-based limits. At the time of adoption of the Euro 5/6 regulation, its mass-based PM emission limits could only be met by closed particulate filters. Number-based PM limits would prevent the possibility that in the future open filters are developed that meet the PM mass limit but enable a high number of ultra fine particles to pass.

Emission Standards
Emission standards for passenger cars and light commercial vehicles (vehicle categories M1 and N1, respectively) are summarized in the following tables. Since the Euro 2 stage, EU regulations introduce different emission limits for diesel and gasoline vehicles. Diesels have more stringent CO standards but are allowed higher NOx. Gasoline vehicles are exempted from PM standards through the Euro 4 stage. Euro 5/6 regulations introduce PM mass emission standards, numerically equal to those for diesels, for gasoline cars with DI engines.

All dates listed in the tables refer to new type approvals. The EC Directives also specify a second date—one year later (unless indicated otherwise)—which applies to first registration (entry into service) of existing, previously type-approved vehicle models.

Table 1

EU Emission Standards for Passenger Cars (Category M1*), g/km

* At the Euro 1..4 stages, passenger vehicles > 2,500 kg were type approved as Category N1 vehicles
† Values in brackets are conformity of production (COP) limits
a - until 1999.09.30 (after that date DI engines must meet the IDI limits)
b - 2011.01 for all models
c - and NMHC = 0.068 g/km
d - applicable only to vehicles using DI engines
e - proposed to be changed to 0.003 g/km using the PMP measurement procedure


Table 2

EU Emission Standards for Light Commercial Vehicles, g/km

† For Euro 1/2 the Category N1 reference mass classes were Class I ≤ 1250 kg, Class II 1250-1700 kg, Class III > 1700 kg.
a - until 1999.09.30 (after that date DI engines must meet the IDI limits)
b - 2011.01 for all models
c - 2012.01 for all models
d - applicable only to vehicles using DI engines
e - proposed to be changed to 0.003 g/km using the PMP measurement procedure
f - and NMHC = 0.068 g/km
g - and NMHC = 0.090 g/km
h - and NMHC = 0.108 g/km


Particle Number Emissions.
Under the draft implementing legislation, a particle number emission limit of 5 × 1011 km-1 (PMP method, NEDC test) becomes effective at the Euro 5/6 stage for all categories of diesel vehicles (M, N1, N2). The particle number limit must be met in addition to the PM mass emission limits listed in the above tables.

The particle number emission limit is not applicable to gasoline vehicles.

Durability.
Useful vehicle life for the purpose of emission regulations is:
• Euro 3 stage—80,000 km or 5 years (whichever occurs first); in lieu of an actual deterioration run, manufacturers may use the following deterioration factors: 1.2 for CO, HC, NOx (gasoline) or 1.1 for CO, NOx, HC+NOx and 1.2 for PM (diesel).
• Euro 4 stage—100,000 km or 5 years, whichever occurs first.
• Euro 5/6 stage—in-service conformity: 100,000 km or 5 years; durability testing of pollution control devices for type approval: 160,000 km or 5 years (whichever occurs first).

Other Provisions.
The regulations include several additional provisions, such as:
• EU Member States may introduce tax incentives for early introduction of vehicles that comply with future emission standards.
• Requirement for low temperature emission test (-7°C) for gasoline vehicles effective 2002 [Directive 2001/100/EC]. The limits for cars are 15 g/km for CO and 1.8 g/km for HC, measured over the urban part of the test only.
• Onboard diagnostic (OBD) requirements for emission systems.

OBD Requirements

Starting from the Euro 3 stage, vehicles must be equipped with an onboard diagnostic system for emission control. Driver must be notified in case of a malfunction or deterioration of the emission system that would cause emissions to exceed mandatory thresholds, as listed in Table 3 (Euro 4 limits are proposed). The thresholds are based on the NEDC (cold start ECE+EUDC) test. To distinguish from the US OBD, the European limits are also referred to as the EOBD (European OBD).

Table 3

European OBD Threshold Limits, g/km

A number of OBD issues were clarified in the Directive 1999/102/EC. Dates of OBD application to gas fueled (LPG or NG) vehicles are given in Directive 2001/1/EC.


Source: http://www.dieselnet.com/standards/eu/ld.php

 

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European Standards - Heavy Trucks

Regulatory Framework

European emission regulations for new heavy-duty diesel engines are commonly referred to as Euro I ... VI. Sometimes Arabic numerals are also used (Euro 1 ... 6). We will use Roman numerals when referencing standards for heavy-duty engines, and reserve Arabic numerals for light-duty vehicle standards.

The emission standards apply to all motor vehicles with a “technically permissible maximum laden mass” over 3,500 kg, equipped with compression ignition engines or positive ignition natural gas (NG) or LPG engines.

The regulations were originally introduced by the Directive 88/77/EEC, followed by a number of amendments. In 2005, the regulations were re-cast and consolidated by the Directive 05/55/EC. Beginning with the Euro VI stage, the legislation will be simplified, as “directives”—which need to be transposed into all of the national legislations—will be replaced by “regulations” which are directly applicable. The following are some of the most important rulemaking steps in the heavy-duty engine regulations:
• Euro I standards were introduced in 1992, followed by the introduction of Euro II regulations in 1996. These standards applied to both truck engines and urban buses, the urban bus standards, however, were voluntary.
• In 1999, the EU adopted Directive 1999/96/EC, which introduced Euro III standards (2000), as well as Euro IV/V standards (2005/2008). This rule also set voluntary, stricter emission limits for extra low emission vehicles, known as “enhanced environmentally friendly vehicles” or EEVs.
• In 2001, the European Commission adopted Directive 2001/27/EC which prohibits the use of emission “defeat devices” and “irrational” emission control strategies, which would be reducing the efficiency of emission control systems when vehicles operate under normal driving conditions to levels below those determined during the emission testing procedure.
• Directive 2005/55/EC adopted by the EU Parliament in 2005 introduced durability and OBD requirements, as well as re-stated the emission limits for Euro IV and Euro V which were originally published in 1999/96/EC. In a “split-level” regulatory approach, the technical requirements pertaining to durability and OBD—including provisions for emission systems that use consumable reagents—have been described by the Commission in Directive 2005/78/EC.
• In December 2007, the Commission published a proposal for Euro VI emission standards [COM(2007) 851]. The new emission limits, comparable in stringency to the US 2010 standards, would become effective from 2013/2014. The proposal represents the political part of the regulation. In the “split-level” approach, the technical details will be developed by the Commission at a later date.

Emission Standards

The following table contains a summary of the emission standards and their implementation dates. Dates in the tables refer to new type approvals; the dates for all type approvals are in most cases one year later (EU type approvals are valid longer than one year).

Table 1

EU Emission Standards for HD Diesel Engines, g/kWh (smoke in m-1)

† Proposal (2008.12.16)
a - for engines of less than 0.75 dm3 swept volume per cylinder and a rated power speed of more than 3000 min-1

Since the Euro III standard (2000), the earlier steady-state engine test ECE R-49 has been replaced by two cycles: the European Stationary Cycle (ESC) and the European Transient Cycle (ETC). Smoke opacity is measured on the European Load Response (ELR) test. The following testing requirements apply:

Compression ignition (diesel) engines:
• Euro III:
Conventional diesel engines: ESC/ELR test
Diesel engines with “advanced aftertreatment” (NOx aftertreatment or DPFs) and EEVs: ESC/ELR + ETC
• Euro IV and later: ESC/ELR + ETC
Positive ignition gas (natural gas, LPG) engines, Euro III and later: ETC cycle
Emission standards for diesel engines that are tested on the ETC test cycle, as well as for heavy-duty gas engines, are summarized in Table 2.

Table 2

Emission Standards for Diesel and Gas Engines, ETC Test, g/kWh

† Proposal (2008.12.16)
a - for gas engines only (Euro III-V: NG only; Euro VI: NG + LPG)
b - not applicable for gas fueled engines at the Euro III-IV stages
c - for engines with swept volume per cylinder < 0.75 dm3 and rated power speed > 3000 min-1
d - THC for diesel engines

Euro VI Proposal. Additional provisions of the Euro VI proposal include:
• An ammonia (NH3) concentration limit of 10 ppm applies to diesel (ESC + ETC) and gas (ETC) engines.
• A particle number limit, in addition to the mass limit, is to be introduced no later than 1 April 2010. The number limit would prevent the possibility that the Euro VI PM mass limit is met using technologies (such as “open filters”) that would enable a high number of ultra fine particles to pass.
• The world-harmonized test cycles—WHSC and WHTC—will be used for Euro VI testing. WHSC/WHTC based limit values will be introduced once correlation factors with the current ESC/ETC tests are established, but no later than 1 April 2010.
• A maximum limit for the NO2 component of NOx emissions may be defined at a later time.

Emission Durability.
Effective October 2005 for new type approvals and October 2006 for all type approvals, manufacturers should demonstrate that engines comply with the emission limit values for useful life periods which depend on the vehicle category, as shown in the following table.


Table 3

Emission Durability Periods

Effective October 2005 for new type approvals and October 2006 for all type approvals, type approvals also require confirmation of the correct operation of the emission control devices during the normal life of the vehicle under normal conditions of use (“conformity of in-service vehicles properly maintained and used”).

Early Introduction of Clean Engines. EU Member States are allowed to use tax incentives in order to speed up the marketing of vehicles meeting new standards ahead of the regulatory deadlines. Such incentives have to comply with the following conditions:
• they apply to all new vehicles offered for sale on the market of a Member State which comply in advance with the mandatory limit values set out by the Directive,
• they cease when the new limit values come into effect
• for each type of vehicle they do not exceed the additional cost of the technical solutions introduced to ensure compliance with the limit values.

Early introduction of cleaner engines can be also stimulated by such financial instruments as preferential road toll rates. In Germany, road toll discounts were introduced in 2005 which stimulated early launch of Euro V trucks.

Under the Euro VI proposal, incentives can also be given for scrapping existing vehicles or retrofitting them with emission controls.

source: http://www.dieselnet.com/standards/eu/hd.php

 

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US Light Duty Tier 1

Introduction

Two sets of standards have been defined for light-duty vehicles in the Clean Air Act Amendments (CAAA) of 1990:
• Tier 1 standards, which were published as a final rule on June 5, 1991 and phased-in progressively between 1994 and 1997.
• Tier 2 standards, which were adopted on December 21, 1999, with a phase-in implementation schedule from 2004 to 2009.

Tier 1 standards applied to all new light-duty vehicles (LDV), such as passenger cars, light-duty trucks, sport utility vehicles (SUV), minivans and pick-up trucks. The LDV category included all vehicles of less than 8500 lb gross vehicle weight rating, or GVWR (i.e., vehicle weight plus rated cargo capacity). LDVs were further divided into the following sub-categories:
• passenger cars
• light light-duty trucks (LLDT), below 6000 lbs GVWR
• heavy light-duty trucks (HLDT), above 6000 lbs GVWR

FTP Emission Standards
The Tier 1 emission standards are summarized in Table 1. Car and light truck emissions are measured over the Federal Test Procedure (FTP 75) test and expressed in g/mile.

Table 1

EPA Tier 1 Emission Standards for Passenger Cars and Light-Duty Trucks, FTP 75, g/mi

1 - Useful life 120,000 miles/11 years for all HLDT standards and for THC standards for LDT
† - More relaxed NOx limits for diesels applicable to vehicles through 2003 model year

Abbreviations:
LVW - loaded vehicle weight (curb weight + 300 lbs)
ALVW - adjusted LVW (the numerical average of the curb weight and the GVWR)
LLDT - light light-duty truck (below 6,000 lbs GVWR)
HLDT - heavy light-duty truck (above 6,000 lbs GVWR)

SFTP Emission Standards
In addition to the FTP 75 test, a Supplemental Federal Test Procedure (SFTP) was phased-in between 2000 and 2004. The SFTP includes additional test cycles to measure emissions during aggressive highway driving (US06), and also to measure urban driving emissions while the vehicle’s air conditioning system is operating (SC03).

The Tier 1 SFTP standards, which applied to NMHC+NOx and CO emissions, are summarized in Table 2. The NMHC+NOx standards are weighted, while CO standards are standalone for US06 and SC03 with an option for weighted standard. Weighting for NMHC+NOx and optional weighting for CO is SFTP = 0.35 × FTP + 0.28 × US06 + 0.37 × SC03. Intermediate life (50,000 mi) standards are shown in parentheses.

Table 2

EPA Tier 1 SFTP Standards

National LEV Program
On December 16, 1997, EPA finalized the regulations for the National Low Emission Vehicle (NLEV) program [63 FR 926, 7 Jan 1998]. The NLEV was a voluntary program that came into effect through an agreement by the northeastern states and the auto manufacturers. It provided more stringent emission standards for the transitional period before the introduction of Tier 2 regulations. Starting in the northeastern states in model year 1999 and nationally in model year 2001, new cars and light light-duty trucks had to meet tailpipe standards that were more stringent than EPA could legally mandate prior to model year 2004. However, after the NLEV program was agreed upon, these standards were enforceable in the same manner as any other federal new motor vehicle program.

The National LEV program harmonized the federal and California motor vehicle standards and provided emission reductions that were basically equivalent to the California Low Emission Vehicle program. The program was phased-in through schedules that required car manufacturers to certify a percentage of their vehicle fleets to increasingly cleaner standards (TLEV, LEV, ULEV). The National LEV program extended only to lighter vehicles and did not include the Heavy LDT (HLDT, GVWR>6,000 lbs) vehicle category.

Source: http://www.dieselnet.com/standards/us/ld.php

 

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US Light Duty Tier 2

Introduction

The Tier 2 regulation introduced more stringent numerical emission limits relative to the previous Tier 1 requirements, and a number of additional changes that made the standards more stringent for larger vehicles. Under the Tier 2 regulation, the same emission standards apply to all vehicle weight categories, i.e., cars, minivans, light-duty trucks, and SUVs have the same emission limit.

In Tier 2, the applicability of light-duty emission standards has been extended to cover some of the heavier vehicle categories. The Tier 1 standards applied to vehicles up to 8500 lbs GVWR. The Tier 2 standards apply to all vehicles that were covered by Tier 1 and, additionally, to “medium-duty passenger vehicles” (MDPV). The MDPV is a new class of vehicles that are rated between 8,500 and 10,000 lbs GVWR and are used for personal transportation. This category includes primarily larger SUVs and passenger vans. Table 1 outlines and defines the vehicle categories used in the EPA Tier 2 standards. Engines in commercial vehicles above 8500 lbs GVWR, such as cargo vans or light trucks, continue to certify to heavy-duty engine emission standards.

Table 1

Vehicle Categories Used in EPA Tier 2 Standards

1 - LVW (loaded vehicle weight) = curb weight + 300 lb
2 - ALVW (adjusted loaded vehicle weight) = average of GVWR and curb weight
3 - Manufacturers may alternatively certify engines for diesel fueled MDPVs through the heavy-duty diesel engine regulations

The same emission limits apply to all vehicles regardless of the fuel they use. That is, vehicles fueled by gasoline, diesel, or alternative fuels all must meet the same standards. Since light-duty emission standards are expressed in grams of pollutants per mile, vehicles with large engines (such light trucks or SUVs) have to use more advanced emission control technologies than vehicles with smaller engines in order to meet the standards.

The EPA Tier 2 program uses a three-tiered compliance strategy. Pre-production evaluation is used to certify vehicles prior to sale. A production evaluation is used on the assembly line for early evaluation of production vehicles. Finally in-use evaluation is used to verify properly maintained vehicles after several years of use.

The Tier 2 regulation brought new requirements for fuel quality. Cleaner fuels are required by advanced emission aftertreatment devices (e.g., catalysts and particulate filters) that are needed to meet the regulations.
• Sulfur Levels in Gasoline—The program requires that most refiners and importers meet a corporate average gasoline sulfur standard of 120 ppm and a cap of 300 ppm beginning in 2004. Since 2006, the average standard has been reduced to 30 ppm with an 80 ppm sulfur cap. Temporary, less stringent standards applied to some small refiners through 2007. In addition, temporary, less stringent standards applied to a limited geographic area in the western USA for the 2004-2006 period.
• Diesel Fuel Quality—Diesel fuel of maximum sulfur level of 15 ppm (known as the ultra low sulfur diesel, ULSD) was made available for highway use beginning in June 2006. The reduction of sulfur content in diesel fuel was legislated by the EPA as a part of the 2007-2010 emission regulation for heavy-duty engines.


Tier 2 Certification Bins

The Tier 2 emission standards are structured into 8 permanent and 3 temporary certification levels of different stringency, called “certification bins”, and an average fleet standard for NOx emissions. Vehicle manufacturers have a choice to certify particular vehicles to any of the available bins. When fully implemented in 2009, the average NOx emissions of the entire light-duty vehicle fleet sold by each manufacturer has to meet the average NOx standard of 0.07 g/mi. The temporary certification bins (bin 9, 10, and an MDPV bin 11) with more relaxed emission limits are available in the phase-in period and expire after the 2008 model year.

Tier 2 vehicles are those meeting the requirements of one of the available bins and that are used to meet the requirement that a percentage of the fleet have average NOx emissions of 0.07 g/mile. During the phase-in period, the rest of the fleet not used to comply with the 0.07 g/mile NOx average are referred to as interim non-Tier 2 vehicles. They must still meet the requirements of one of the available bins but have more relaxed fleet average requirements.

The emission standards for all pollutants (certification bins) when tested on the Federal Test Procedure (FTP) are shown in Table 2. Where intermediate useful life exhaust emission standards are applicable, such standards are applicable for five years or 50,000 miles, whichever occurs first. The vehicle “full useful life” period for LDVs and light LDTs has been extended to 120,000 miles or ten years whichever occurs first. For heavy LDTs and MDPVs, it is 11 years or 120,000 miles whichever occurs first. Manufacturers may elect to optionally certify to the Tier 2 exhaust emission standards for 150,000 miles to gain NOx credits or to opt out of intermediate life standards. In such cases, useful life is 15 years or 150,000 miles, whichever occurs first. For interim non-Tier 2 LDV/LLDTs, the useful life is 10 years or 100,000 miles, whichever occurs first.

Table 2

Tier 2 Emission Standards, FTP 75, g/mi

* for diesel fueled vehicle, NMOG (non-methane organic gases) means NMHC (non-methane hydrocarbons)
† average manufacturer fleet NOx standard is 0.07 g/mi for Tier 2 vehicles

a - Bin deleted at end of 2006 model year (2008 for HLDTs)
b - The higher temporary NMOG, CO and HCHO values apply only to HLDTs and MDPVs and expire after 2008
c - An additional temporary bin restricted to MDPVs, expires after model year 2008
d - Optional temporary NMOG standard of 0.195 g/mi (50,000) and 0.280 g/mi (full useful life) applies for qualifying LDT4s and MDPVs only
e - Optional temporary NMOG standard of 0.100 g/mi (50,000) and 0.130 g/mi (full useful life) applies for qualifying LDT2s only
f - 50,000 mile standard optional for diesels certified to bins 9 or 10

It may be noted that bin 5 has a NOx limit of 0.07 g/mi, which is equal to the fleet average NOx standard. Therefore, NOx emissions from vehicles certified to bins higher than bin 5 must be offset by selling a sufficient number of vehicles certified to bins lower than bin 5.

The EPA bins cover California LEV II emission categories, to make certification to the federal and California standards easier for vehicle manufacturers.
Tier 2 Emission Standards Phase-In

The Tier 2 standards are phased-in between 2004 and 2009, as shown in Table 3. For new passenger cars (LDVs) and LLDTs, Tier 2 standards phase-in begins in 2004, with full implementation in the 2007 model year. For HLDTs and MDPVs, the Tier 2 standards are phased in beginning in 2008, with full compliance in 2009.

Up through and including model year 2008, manufacturers must calculate separate fleet average NOx emissions for the portion of their fleet of LDV/LLDT and HLDT/MDPV Tier 2 vehicles being phased-in. Both must comply with the 0.07 g/mile standard (equivalent to bin 5) for the required phase-in percentage for that year.

During the phase-in period, vehicles not used to meet the Tier 2 FTP phase-in requirements must still comply with the full useful life and intermediate useful life FTP exhaust emission standards for one of the available bins listed in Table 2 (i.e., at least bin 10 for LDV/LDTs and bin 11 for MDPVs).

During the period 2004-2007, all passenger cars (LDVs) and LLDTs not certified to the primary Tier 2 standards (i.e., the 0.07 g/mile fleet average NOx) must meet an interim average standard of 0.30 g/mi NOx, equivalent to bin 9 and the NLEV standards for LDVs.

During the period 2004-2008, HLDTs and MDPVs not certified to the final Tier 2 must meet an interim average standard of 0.20 g/mi NOx (equivalent to bin 8) following the schedule in Table 2. Those vehicles not covered by the phase-in requirements are still subject to the emission standards listed in Table 1 (i.e., bin 10, 0.6 g/mi NOx, for HLDTs and bin 11, 0.9 g/mi NOx, for MDPVs).

Through model year 2007, a manufacturer may opt to certify diesel engines for MDPVs through the heavy-duty diesel engine requirements instead of the entire vehicle through the light-duty regulations. These vehicles cannot be used for compliance with phase-in requirements for interim non-Tier 2 MDPVs.

Table 3

Phase-In Percentages for Tier 2 Requirements

a - Percentage of LDV/LLDTs that must meet Tier 2 requirements
b - Percentage of HLDT/MDPVs that must meet Tier 2 requirements
c - Percentage of non-Tier 2 HLDT/MDPVs that must meet interim non-Tier 2 fleet average NOx requirements


Supplemental Exhaust Emission Standards

In addition to meeting the FTP cycle requirements of Table 2, certification of a vehicles requires that it also meet supplemental exhaust emission standards (US06 and SC03 driving cycles). These must be met by LDV and LDTs but not MDPVs, alternative fueled LDV/LDTs, or flexible fueled LDV/LDTs when operated on a fuel other than gasoline or diesel. With some exceptions, manufacturers must comply with 4000 mile and full useful life SFTP (supplemental federal test procedure) standards. The 4000 mile SFTP standards for NMHC+NOx and CO are outlined in Table 4 and are based on vehicle weight classification only.

Table 4

4000 mile SFTP standards for Tier 2 LDVs and LDTs, g/mi

Full useful life
Tier 2 SFTP standards for NMHC+NOx, PM and CO are based on both vehicle weight classification and the certification bin applicable to that vehicle. They are equal to the Tier 1 SFTP standards minus 35% of the difference between the Tier 1 and Tier 2 FTP standards:

SFTP Standard = Tier 1 SFTP - [0.35 × (Tier 1 FTP - Tier 2 FTP)]

For example, an LDT4 certified to bin 10 would have the Tier 2 SFTP standards as shown in Table 5.

Table 5

Example SFTP Standards (LDT4, Bin 10), g/mi

a - Available from 40 CFR 86.1811-04
b - Sum of NOx and NMHC standards
c - Sum of NOx and NMOG standards
d - Tier 1 FTP standard

Full useful life SFTP compliance is determined by weighting the emission test results as follows:

0.35(FTP) + 0.28(US06) + 0.37(SC03)

and comparing the result with the calculated SFTP standard.

With the exception of HLDTs and bin 10 LDV/LLDTs, interim non-Tier 2 vehicles must meet Tier 2 SFTP requirements. Interim non-Tier 2 HLDTs need only meet 2002 SFTP requirements and interim non-Tier 2 bin 10 LDV/LLDTs can meet Tier 1 SFTP requirements. SFTP standards for PM are not applicable to interim non-Tier 2 LDV/Ts.

Gasoline fueled LDV/Ts and MDPVs must also meet cold temperature limits—measured on the FTP cycle at 20°F (-7°C)—for CO and certification short test limits for raw CO and HC concentrations that do not apply to diesels.

The maximum projected NOx emissions measured on the federal Highway Fuel Economy Test (HWFET) must not be greater than 1.33 times the applicable FTP NOx standard. This standard is not applicable to MDPVs.

The Tier 2 regulation also contains special in-use standards for:
• NOx and NMOG emissions that apply to apply to bin 5, 4, 3 and 2 LDV/LLDTs produced up through the 2008 model year and HLDT/MDPVs produced up through the 2010 model year,
• NOx and PM emissions for diesel vehicles certified to bin 10,
• High altitude NOx emissions for 2007-2009 model year diesel vehicles certified to bins 7 and 8.

Table 6 summarizes the different vehicle categories and their testing requirements.

Table 6

Vehicle Categories And Applicable Tests

1 - Manufacturers may alternatively certify engines for diesel fueled MDPVs through the heavy-duty diesel engine regulations
2 - Does not apply to interim Tier 2 vehicles

 

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Other Provisions

For Tier 2 and interim non-Tier 2 vehicles beginning with the 2004 model year, manufacturer’s must ensure that the complete exhaust system has been designed to facilitate leak-free (i.e. leakage is controlled so as not to lead to the emissions exceeding the limits) assembly, installation and operation for the full useful life of the vehicle. This covers all components from the engine block manifold gasket surface to a point sufficiently past the last catalyst and oxygen sensor in the system to assure that leaks beyond that point will not permit air to reach the oxygen sensor or catalyst under normal operating conditions.

No crankcase emissions are allowed to be discharged into the ambient atmosphere from any 2001 and later model year vehicles certified to these standards.

NOx Credits and Deficits. A manufacturer may generate Tier 2 or interm non-Tier 2 NOx credits or deficits depending on whether its fleet average NOx emissions exceed or are less than the fleet average standard. Credits may be banked for future use or traded to another manufacturer. If a manufacturer has a NOx deficit for a given model year, it must obtain sufficient credits from vehicles produced by itself or another manufacturer no later than three years after the year of the deficit. For example, if a manufacturer calculates that it has a NOx credit deficit for the 2008 model year, it must obtain sufficient NOx credits to offset that deficit from its own production or that of other manufacturers’ 2011 or earlier model year vehicles.

Interim non-Tier 2 NOx credits for LDV/LLDTs and HLDT/MDPVs must be generated, calculated, tracked, averaged, banked, traded, accounted for and reported upon separately from Tier 2 credits. They may not be used to meet the Tier 2 fleet average NOx standard and vise versa. Interim non-Tier 2 NOx credits from HLDT/MDPVs may not be used to meet the fleet average NOx standard for interim non-Tier 2 LDV/LLDTs, and vise versa.

Direct Ozone Reducing Devices. A manufacturer may obtain NMOG credit for use of direct ozone reducing devices in certifying to the exhaust NMOG standards and for use in complying with the in-use standards. This credit effectively allows the manufacturer to increase the exhaust NMOG emission standards by the amount of the applicable credit. For example, if the applicable NMOG credit was 0.01 g/mi, and the vehicle was being certified in Bin 5, exhaust NMOG emissions must be no greater than 0.10 g/mi, as opposed to the normal NMOG certification standard of 0.09 g/mi for Bin 5.


Soruce: http://www.dieselnet.com/standards/us/ld_t2.php

 

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US Heavy Duty

Applicability and Test Cycles

The following emission standards apply to new diesel engines used in heavy-duty highway vehicles. The current federal definition of a compression-ignition (diesel) engine is based on the engine cycle, rather than the ignition mechanism, with the presence of a throttle as an indicator to distinguish between diesel-cycle and otto-cycle operation. Regulating power by controlling the fuel supply in lieu of a throttle corresponds with lean combustion and the diesel-cycle operation (this allows the possibility that a natural gas-fueled engine equipped with a sparkplug is considered a compression-ignition engine).

Heavy-duty vehicles are defined as vehicles of GVWR (gross vehicle weight rating) of above 8,500 lbs in the federal jurisdiction and above 14,000 lbs in California (model year 1995 and later). Diesel engines used in heavy-duty vehicles are further divided into service classes by GVWR, as follows.
• Light heavy-duty diesel engines: 8,500 < LHDDE < 19,500 (14,000 < LHDDE < 19,500 in California, 1995+)
• Medium heavy-duty diesel engines: 19,500 ≤ MHDDE ≤ 33,000
• Heavy heavy-duty diesel engines (including urban bus): HHDDE > 33,000

Under the federal light-duty Tier 2 regulation (phased-in beginning 2004) vehicles of GVWR up to 10,000 lbs used for personal transportation have been re-classified as “medium-duty passenger vehicles” (MDPV - primarily larger SUVs and passenger vans) and are subject to the light-duty vehicle legislation. Therefore, the same diesel engine model used for the 8,500 - 10,000 lbs vehicle category may be classified as either light- or heavy-duty and certified to different standards, depending on the application.
Current federal regulations do not require that complete heavy-duty diesel vehicles be chassis certified, instead requiring certification of their engines (as an option, complete heavy-duty diesel vehicles under 14,000 lbs can be chassis certified). Consequently, the basic standards are expressed in g/bhp•hr and require emission testing over the Transient FTP engine dynamometer cycle (however, chassis certification may be required for complete heavy-duty gasoline vehicles with pertinent emission standards expressed in g/mile).

Additional emission testing requirements, first introduced in 1998, include the following:
• Supplemental Emission Test (SET): A steady-state test to ensure that heavy-duty engine emissions are controlled during steady-state type driving, such as a line-haul truck operating on a freeway. SET emission limits are numerically equal to the FTP limits.
• Not-to-Exceed (NTE) testing: Driving of any type that could occur within the bounds of a pre-defined NTE control area, including operation under steady-state or transient conditions and under varying ambient conditions. NTE emission limits are typically higher than the FTP limits.
These tests were introduced for most signees of the 1998 Consent Decrees between the EPA and engine manufacturers for the period 1998 - 2004. Federal regulations require the supplemental testing from all engine manufacturers effective 2007. In California, the tests are required for all engines effective model year 2005.

Model Year 1987-2003
Model year 1988-2003 US federal (EPA) and 1987-2003 California (ARB) emission standards for heavy-duty diesel truck and bus engines are summarized in the following tables. Applicable to the 1994 and following year standards, sulfur content in the certification fuel has been reduced to 500 ppm wt.

Table 1

EPA Emission Standards for Heavy-Duty Diesel Engines, g/bhp•hr

Table 2

California Emission Standards for Heavy-Duty Diesel Engines, g/bhp•hr

Useful Life and Warranty Periods
Compliance with emission standards has to be demonstrated over the useful life of the engine, which was adopted as follows (federal & California):
• LHDDE—8 years/110,000 miles (whichever occurs first)
• MHDDE—8 years/185,000 miles
• HHDDE—8 years/290,000 miles

Federal useful life requirements were later increased to 10 years, with no change to the above mileage numbers, for the urban bus PM standard (1994+) and for the NOx standard (1998+).

The emission warranty period is 5 years/100,000 miles (5 years/100,000 miles/3,000 hours in California), but no less than the basic mechanical warranty for the engine family.

Clean Fuel Fleet Program
Table 3 shows a voluntary Clean Fuel Fleet (CFF) emission standard. It is a federal standard that applies to 1998-2003 model year engines, both CI and SI, over 8,500 lbs GVWR. In addition to the CFF standard, vehicles must meet applicable conventional standards for other pollutants.

Table 3

Clean Fuel Fleet Program for Heavy-Duty SI and CI Engines, g/bhp•hr

* LEV - low emission vehicle; ILEV - inherently low emission vehicle; ULEV - ultra low emission vehicle; ZEV - zero emission vehicle

Model Year 2004 and Later
In October 1997, EPA adopted new emission standards for model year 2004 and later heavy-duty diesel truck and bus engines. These standards reflects the provisions of the Statement of Principles (SOP) signed in 1995 by the EPA, California ARB, and the manufacturers of heavy-duty diesel engines. The goal was to reduce NOx emissions from highway heavy-duty engines to levels approximately 2.0 g/bhp•hr beginning in 2004. Manufacturers have the flexibility to certify their engines to one of the two options shown in Table 4.

Table 4

EPA Emission Standards for MY 2004 and Later HD Diesel Engines, g/bhp•hr

All emission standards other than NMHC and NOx applying to 1998 and later model year heavy duty engines (Table 1) will continue at their 1998 levels.
EPA established revised useful engine lives, with significantly extended requirements for the heavy heavy-duty diesel engine service class, as follows:
• LHDDE—110,000 miles/10 years
• MHDDE—185,000 miles/10 years
• HHDDE—435,000 miles/10 years/22,000 hours

The emission warranty remains at 5 years/100,000 miles.

With the exception of turbocharged and supercharged diesel fueled engines, discharge of crankcase emissions is not allowed for any new 2004 or later model year engines.

The federal 2004 standards for highway trucks are harmonized with California standards, with the intent that manufacturers can use a single engine or machine design for both markets. However, California certifications for model years 2005-2007 additionally require SET testing, and NTE limits of 1.25 × FTP standards. California also adopted more stringent standards for MY 2004-2006 engines for public urban bus fleets.

Consent Decrees
In October 1998, a court settlement was reached between the EPA, Department of Justice, California ARB and engine manufacturers (Caterpillar, Cummins, Detroit Diesel, Volvo, Mack Trucks/Renault and Navistar) over the issue of high NOx emissions from heavy-duty diesel engines during certain driving modes. Since the early 1990’s, the manufacturers used engine control software that caused engines to switch to a more fuel efficient (but higher NOx) driving mode during steady highway cruising. The EPA considered this engine control strategy an illegal “emission defeat device”.

Provisions of the Consent Decree included the following:
• Civil penalties for engine manufacturers and requirements to allocate funds for pollution research
• Upgrading existing engines to lower NOx emissions
• Supplemental Emission Test (steady-state) with a limit equal to the FTP standard and NTE limits of 1.25 × FTP (with the exception of Navistar)
• Meeting the 2004 emission standards by October 2002, 15 months ahead of time


Model Year 2007 and Later
On December 21, 2000 the EPA signed emission standards for model year 2007 and later heavy-duty highway engines (the California ARB adopted virtually identical 2007 heavy-duty engine standards in October 2001). The rule includes two components: (1) emission standards, and (2) diesel fuel regulations.

The first component of the regulation introduces new, very stringent emission standards, as follows:
• PM—0.01 g/bhp-hr
• NOx—0.20 g/bhp-hr
• NMHC—0.14 g/bhp-hr

The PM emission standard will take full effect in the 2007 heavy-duty engine model year. The NOx and NMHC standards will be phased in for diesel engines between 2007 and 2010. The phase-in would be on a percent-of-sales basis: 50% from 2007 to 2009 and 100% in 2010 (gasoline engines are subject to these standards based on a phase-in requiring 50% compliance in 2008 and 100% compliance in 2009). Very few engines meeting the 0.20 g/bhp-hr NOx requirement will actually appear before 2010. In 2007, most manufacturers opted instead to meet a Family Emission Limit (FEL) around 1.2-1.5 g/bhp-hr NOx for most of their engines with a few manufacturers still certifying some of their engines as high as 2.5 g/bhp-hr NOx+NMHC.

In addition to transient FTP testing, emission certification requirements also include:
• SET test, with limits equal to the FTP standards, and
• NTE testing with limits of 1.5 × FTP standards for engines meeting a NOx FEL of 1.5 g/bhp-hr or less and 1.25 × FTP standards. for engines with a NOx FEL higher than 1.5 g/bhp-hr.

Effective for the 2007 model year, the regulation maintains the earlier crankcase emission control exception for turbocharged heavy-duty diesel fueled engines but requires that if they are emitted to the atmosphere, they be added to the exhaust emissions during all testing. In this case, the deterioration of crankcase emissions must also be accounted for in exhaust deterioration factors.

The diesel fuel regulation limits the sulfur content in on-highway diesel fuel to 15 ppm (wt.), down from the previous 500 ppm. Refiners will be required to start producing the 15 ppm S fuel beginning June 1, 2006. At the terminal level, highway diesel fuel sold as low sulfur fuel must meet the 15 ppm sulfur standard as of July 15, 2006. For retail stations and wholesale purchasers, highway diesel fuel sold as low sulfur fuel must meet the 15 ppm sulfur standard by September 1, 2006.

Refiners can also take advantage of a temporary compliance option that will allow them to continue producing 500 ppm fuel in 20% of the volume of diesel fuel they produce until December 31, 2009. In addition, refiners can participate in an averaging, banking and trading program with other refiners in their geographic area.

Ultra low sulfur diesel fuel has been introduced as a “technology enabler” to pave the way for advanced, sulfur-intolerant exhaust emission control technologies, such as catalytic diesel particulate filters and NOx catalysts, which will be necessary to meet the 2007 emission standards.

The EPA estimates the cost of reducing the sulfur content of diesel fuel will result in a fuel price increase of approximately 4.5 to 5 cents per gallon. The EPA also estimates that the new emission standards will cause an increase in vehicle costs between $1,200 to $1,900 (for comparison, new heavy-duty trucks typically cost up to $150,000 and buses up to $250,000).


Source: http://www.dieselnet.com/standards/us/hd.php

 

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US California Standards

Introduction
California emission standards have been traditionally more stringent than the EPA requirements, but their evolution and structure is similar to that of the federal legislation:
• Tier 1/LEV California emission standards extended through the year 2003.
• LEV II California regulations became effective in 2004.

A number of other states have adopted emission standards equivalent to the California LEV II legislation, including New York, Massachusetts, Maine and Vermont (adoption of California standards has been also considered by Connecticut, Rhode Island, Pennsylvania, New Jersey, Oregon, and Washington).

Low Emission Vehicle (LEV) Standards
These California emission standards, which applied through model year 2003, were expressed using the following emission categories:
• Tier 1
• Transitional Low Emission Vehicles (TLEV)
• Low Emission Vehicles (LEV)
• Ultra Low Emission Vehicles (ULEV)
• Super Ultra Low Emission Vehicles (SULEV)
• Zero Emission Vehicles (ZEV)

Car manufacturers were required to produce a percentage of vehicles certified to increasingly more stringent emission categories, according to schedules based on vehicle fleet emission averages for each manufacturer. After 2003, Tier 1 and TLEV standards were eliminated as available emission categories.

The same standards for gaseous pollutants applied to diesel- and gasoline-fueled vehicles. PM standards applied to diesel vehicles only. Emissions were measured over the FTP 75 test and are expressed in g/mile. The additional SFTP procedures were phased-in in California between 2001 and 2005.

Table 1

California Emission Standards for Light-Duty Vehicles, FTP 75, g/mi

a - NMHC for all Tier 1 standards

Abbreviations:
LVW - loaded vehicle weight (curb weight + 300 lbs)
LDT - light-duty truck
NMOG - non-methane organic gases
HCHO - formaldehyde


Emission standards for medium-duty vehicles are summarized in Table 2.

Table 2

California Emission Standards for Medium-Duty Vehicles, FTP 75, g/mi

a - NMHC for all Tier 1 standards

Abbreviations:
MDV - medium-duty vehicle (the maximum GVWR from 8,500 to 14,000 lbs). The MDV category is divided into five classes, MDV1 .. MDV5, based on vehicle test weight. The definition of “test weight” in California is identical to the Federal ALVW.
NMOG - non-methane organic gases
HCHO - formaldehyde

Low Emission Vehicle II (LEV II) Standards
On November 5, 1998 the California ARB adopted the LEV II emission standards which extend from the year 2004 until 2010.

Under the LEV II regulation, the light-duty truck and medium-duty vehicle categories of below 8500 lbs gross weight are reclassified and have to meet passenger car requirements, as shown in Table 3. As a result, most pick-up trucks and sport utility vehicles (old MDV4 and MDV5) are required to meet the passenger car emission standards. The reclassification was phased-in by the year 2007.

Under the LEV II standard, NOx and PM standards for all emission categories are significantly tightened. The same standards apply to both gasoline and diesel vehicles (under revisions adopted on November 15, 2001 gasoline vehicles are no longer exempted from the PM standard). Light-duty LEVs and ULEVs certify to a 0.05 g/mi NOx standard, phased-in starting with the 2004 model year. A full useful life PM standard of 0.010 g/mi is introduced for light-duty diesel vehicles and trucks less than 8500 lbs GVWR certifying to LEV, ULEV, and SULEV standards. The TLEV emission category has been eliminated. It is, therefore, believed that the LEV II emission standards can only be met by vehicles fitted with advanced emission control technologies, such as particulate filters and NOx reduction catalysts.


Table 3

California LEV II Emission Standards, Passenger Cars and LDVs < 8500 lbs, g/mi

Table 4

California LEV II Emission Standards, Medium Duty Vehicles, Durability 120,000 miles, g/mi

The LEV II standards also include an extension and tightening of the fleet average standards requiring automakers to reduce fleet emission levels each year through 2010, as well as tightening of evaporative emission standards.


Source: http://www.dieselnet.com/standards/us/ld_ca.php

 

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Crude oil, the source of diesel fuel, varys widely in the amount of sulfer it contains.

Oil sourced from Venezuala is among the world's highest in sulphur content. Higher sulphur crude oil is more expensive to refine into today's low sulphur content fuels.

Source: UNEP