[1] Testing by engine manufacturers and regulatory bodies have found the use of emissions control devices in conjunction with ULSD can reduce the exhaust output of ozone precursors and particulate matter to near-zero levels.
[2] In 1993 the European Union began mandating the reduction of diesel sulfur content and implementing modern ULSD specifications in 1999.
[3][4] The United States started phasing in ULSD requirements for highway vehicles in 2006, with implementation for off-highway applications, such as locomotive and marine fuel, beginning in 2007.
The processing required to reduce sulfur to 15 ppm also removes naturally occurring lubricity agents in diesel fuel.
[citation needed] This decrease in energy content may result in slightly reduced peak power and fuel economy.
The US government estimated that pump prices for diesel fuel increased between 5 and 25 cents per US gallon (1.3 and 6.6 ¢/L) as a result of the transition [citation needed] and, according to the American Petroleum Institute, the domestic refining industry has invested over $8 billion to comply with the new regulations.
[citation needed] TDI engines from 2009 and on are designed to use ULSD exclusively; biodiesel blends are reported to prevent that failure.
[13] 50 ppm sulfur content was first legislated by the South African Department of Minerals and Energy in early 2006, and has been widely available since then.
South Africa's Clean Fuels 2 standard, expected to have begun in 2017, reducing the allowable sulfur content to 1 ppm.
China has limited sulfur in diesel fuel to 150 ppm (equivalent to the Euro III standard).
[16] In July 2000, Hong Kong became the first city in Asia to introduce ULSD, with sulfur content of 50 parts per million (ppm).
[17][18] The shift was carried out directly from Euro-II to Euro-V.[19] Delhi first introduced 50 ppm sulfur diesel on 1 April 2010 as a step aimed at curbing vehicular pollution in the capital.
The Bharat Stage VI with ultra low sulfur content of less than 10 ppm will be standard across the country from April 2020.
In particular, the so-called EU accession countries (primarily in Eastern Europe), have been granted certain temporary exemptions to allow for transition.
Since 2003, a "zero" sulfur with very low aromatic content (less than 1% by volume) diesel fuel has been made available on the Swedish market under the name EcoPar.
It is used wherever the working environment is highly polluted, an example being where diesel trucks are used in confined spaces such as in harbours, inside storage houses, during construction of road and rail tunnels & in vehicles that are predominantly run in city centres.
Slightly different times for transition have applied to each of the countries, but most have been required to reduce the maximum sulfur content to less than 50 ppm since 2005.
For the designated Northern Supply Area, the deadline for reducing the sulfur content of diesel fuel for use in on-road vehicles was 31 August 2007.
It provided additional time to fully turn over the higher-sulfur diesel fuel inventory for on-road use in the distribution system.
The allowable sulfur content for ULSD (15 ppm) is much lower than the previous U.S. on-highway standard for low sulfur diesel (LSD, 500 ppm) which allowed advanced emission control systems to be fitted that would otherwise be damaged and or rendered ineffective by these compounds.
In Europe, diesel-engined automobiles have been much more popular with buyers than has been the case in the U.S. Additionally, the EPA has assisted manufacturers with the transition to tougher emissions regulations by loosening them for model year 2007 to 2010 light-duty diesel engines.
Other requirements effective June 1, 2006, including EPA-authorized language on Product Transfer Documents and sulfur-content testing standards, are designed to prevent misfueling, contamination by higher-sulfur fuels and liability issues.
The EPA deadline for industry compliance to a 15 ppm sulfur content was originally set for July 15, 2006 for distribution terminals, and by September 1, 2006 for retail.
As of December, 2006, the ULSD standard has been in effect according to the amended schedule, and compliance at retail locations was reported to be in place.
Grade 2 diesel fuel is available with 2 different sulfur levels depending on the population density of the location where it is retailed.
As of 2002, much of the former Soviet Union still applied limits on sulfur in diesel fuel substantially higher than in Western Europe.
Euro IV diesel in particular may be available at fueling stations selling to long-distance truck fleets servicing import and export flows between Russia and the EU.