Applications / Automotive / Emission Regulations


EVAL™ enables to produce lighter fuel tanks with very low evaporative emissions.

Emission Regulations

United States Emission Regulations

As environmental policies continue to evolve, several efforts have been made to improve the air quality

Emission regulations for fuel tanks in the United States started in 1990 with the passage of the Clean Air Act.  This Congressional Act was passed as part of a sweeping effort to improve the quality of air by limiting pollution from all sources.  Two agencies then crafted regulations for industries to follow in an effort to comply.

The Environmental Protection Agency (EPA) is a federal agency whose regulations have become the minimum standard for the entire country.  The state of California, being the most severely polluted in the US, crafted stricter regulations of their own (enacted by California Air Resources Board or CARB) and now hold precedent over EPA regulations in that state.


The LEV I, II, III Initiatives in the United States

Other states are free to adopt either the EPA regulations or any other regulation that is more stringent. As a result of this, several states in the northeast have adopted either CARB’s regulations or some variation of it. The CARB regulations are called LEV (low emission vehicle) and were first enforced in 1994.  LEV I was in effect until 2003.  From 2003-2010, LEV II were in effect. With LEV II standards, an average 2010 vehicle produces 10 pounds of smog, compared to a LEV I vehicle that produces an average of 50 pounds. In 2012, LEV III criteria was agreed upon and began being enforced in 2015. These amendments include more stringent standards for both criteria pollutants and greenhouse gases for passenger vehicles. A notable change with LEV III, in regard to fuel tanks, was the standard test fuel. This meant, all LEV III must be certified on E10 (10% ethanol) gasoline.

The EPA Tier Regulations

The EPA regulations are known as Tier regulations. Tier 1 was enforced up to 2004. Tier 2 began in 2004, and is still in effect. At least 45 states follow these regulations. In 2017, Tier 3 will set new vehicle emissions standards. The Tier 3 initiatives reduce both tailpipe and evaporative emissions for passenger vehicles, light-duty trucks, and some heavy-duty trucks.


Evaporative emission regulations

EVOH solution

European Emission Regulations

For many years, the only fuel vapor emission standard used throughout most of Europe was found in ECE R34. This was related only to fuel tank permeation. The test required to meet ECE R34 consisted of placing a partially filled fuel tank in an enclosed chamber at 40°C for 24 hours. The total weight loss could not be more than 20 grams. This is close to the permeation levels of some untreated tanks.

Based upon US regulations, the European Economic Community (EEC) required vehicles to pass a SHED-type evaporative emission test. This test measured emissions from the entire vehicle while it was subjected to a diurnal (1 hour 16-30°C) and hot-soak (1 hour 23-31°C) emission. The limit value of 2 grams per vehicle cycle applies to the entire vehicle and the sum total of all hydrocarbons. More information can be found in Directive 70/220/EEC, updated versions 94/12/EC and 96/69/EC.

Starting in 2000, the European Community required vehicles to meet new regulations which are known as EURO III (or EURO 2000). Euro III, specified in Directive 98/69/EC was introduced from 1st of January 2000 and became fully effective, for the majority of vehicles, on 1st January 2001. The limit value of 2 grams per test cycle was retained, but the duration of testing for tank permeation losses was extended from 1 hour to 24 hours (24 hour 20-35°C diurnal & hot-soak 1 hour 23-31°C). Hence, as with the US regulations, fuel permeation is an important component of the overall evaporative emissions. Euro III legislation is quite close to the enhanced evaporative emission regulations that have been introduced in the US under EPA Tier 1.

However, only a one day diurnal test and not two- and three-day diurnals such as those used in the US test are mentioned and no running loss determination is required. The emission cycle test was also modified for Euro III (and Euro IV) to include measurements of pollutants from the moment the engine starts. In the previous test, measurement commenced after the engine had started and idled for 40 seconds. The new limits, shown below, represent a 30% reduction over Euro II, even though this is not obvious from the figures, due to the more severe test.

Local pollutant emissions from new cars are measured and must comply with strict EU vehicle emission standards (Euro standards). Four of the emissions are covered by the Euro standards: carbon monoxide, hydrocarbons, nitrogen oxides and also (for diesel cars) particulate matter.

Euro IV limits, also specified in Directive 98/69, which started 1st January 2005 and became fully effective on 1st January 2007.

A proven track record

EVAL™ EVOH products are commercially used in multilayer plastic fuel tanks, lines and filler pipes. Over 250 million cars have been produce to date using EVAL™ with no known fuel systems failures related to the EVAL™ product.