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ON HIGHWAY - Europe

European emission regulations for new heavy-duty diesel engines are commonly referred to as Euro I ... V. Sometimes Arabic numerals are also used (Euro 1 ... 5). We will use Roman numerals when referencing standards for heavy-duty engines, and reserve Arabic numerals for light-duty vehicle standards.
The heavy-duty engine 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. 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 or LPG engines.
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.

The Commission is expected to publish a proposal for Euro VI emission standards in 2006. In addition to introducing more stringent emission limits, the Commission is required to review the need to introduce new standards for pollutants that are as yet unregulated, which may be related to the usage of alternative fuels and additive-based emission control systems, and to investigate whether setting an additional limit for particle levels and size is necessary, and, if so, to include it in the proposals.

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).

Changes in the engine test cycles have been introduced in the Euro III standard (2000). The old steady-state engine test cycle 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 applied for type approval of new vehicles according to the Euro III standard (2000):

• Conventional diesel engines were tested over the ESC/ELR test.
• Diesel engines with “advanced aftertreatment” (NOx aftertreatment or DPFs) were tested on both tests, ESC/ELR + ETC.
• Gas engines were tested over the ETC cycle.

For type approval according to the Euro IV (2005) and later limit values and for EEVs, emissions have to be determined on both the ETC and the ESC/ELR tests for all types of diesel engines.
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.

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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.

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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.