Unlike in the aviation and marine sector, fuel specification in the on-road transportation sector are varied depending on the countries. Globally, the countries are going towards ultra-low sulfur fuels. In developed countries including in EU and the U.S., ultra-low sulfur fuels have been used since 2005-2006. In Asia, Japan lead the region with less than 10 ppm sulfur fuels introduced into the market in January 2005. More than a decade later, fuels with high sulfur content are still sold in most countries in Asia, Africa, the Middle East and Pacific. Facing pressure from environmentalists, these countries are focusing on sulfur reduction in their conventional fuels, along with improvement in their conventional fuels, along with improvement in their vehicle emission standards. On the other hand, in more advanced countries where they already have the cleanest possible conventional fuels, alternative fuels vehicles including electric vehicles are getting more attentions. Governments of developing countries are setting higher fuel quality standards to enable the implementation of more stringent vehicle emission standards. However, lack of fuel quality monitoring system in those countries results in the use of off-spec fuels. SGS worldwide market data delivers many examples. In the Philippines, 83% of premium plus gasoline samples have RON of 93 - 96.5 against the minimum requirement of 97 in the period of 2011-2017. Another example: 11.28 vol.% of methanol was found in a gasoline sample in 2016-2017 in the Philippines despite the specifications do not allow methanol to be present. One more example from Pakistan: the Manganese presence in all gasoline samples with concentration from 0.1 to 104 mg/kg in 2003-2017. Prolonged use of off-spec fuels will deteriorate exhaust emissions, damage the vehicles and worsen air quality. Therefore, a good understanding of fuel specifications and implementation of a good fuel quality monitoring system are needed to avoid severe productivity loss due to stalled vehicles on the road