Jan
20
2014
It’s been coming for a number of years, but the reprieve’s over. In 2014, anyone who purchases new off-road diesel-powered equipment, including farm equipment, will be required to use diesel exhaust fluid—also known as DEF—as part of the EPA’s stringent emission standards.
“Diesel-powered trucks and SUVs have been required to use DEF since 2010, and now it’s here for all off-road applications,” said Mick Calvin, business development manager for CountryMark. “It’s one more thing you’re going to have to manage, but with a little planning, it’s not that difficult.”

Calvin said that the use of DEF for off-road equipment was the latest step in the EPA’s continuing efforts to reduce emissions from diesel engines. In a nutshell, DEF is a non-toxic, urea-based liquid solution that is sprayed into the exhaust streams of diesel vehicles that utilize Selective Catalytic Reduction (SCR) technology. The urea in the DEF chemically reacts with nitrous oxide—a greenhouse gas—breaking it down to produce water and nitrogen. As a result, the air expelled from the tailpipe of a vehicle using DEF is actually cleaner than the air coming into the engine.
Calvin’s advice for proper management of DEF boiled down to three basic principles:
Store it properly. If stored in a shop or controlled environment, DEF can have a shelf life of up to two years. However if it is stored outside in direct sunlight, or in sustained temperatures of more than 86 degrees Fahrenheit, it will degrade much quicker. And while Calvin said that DEF below 12 degrees would “turn into Mr. Slushy,” much like liquid fertilizer, it will not degrade at that temperature and will quickly return to its normal state once its engine reservoir warms up. Calvin also said not to over-order DEF. “Given its shelf life, it doesn’t make sense to order a tote if you only need a drum, just to get a lower price per gallon.” Normal DEF usage runs about 3 percent of diesel fuel consumption.
Avoid contamination. Calvin said that DEF is easily contaminated, and that such contamination can affect a diesel engine’s injector nozzles or plug its fuel streams. Although DEF can be ordered in containers featuring a “closed” access system with a spring-loaded valve, most farmers will probably be using an “open” system utilizing caps or plugs on the container. “Make sure you’re putting those caps or plugs back in place as soon as possible,” said Calvin.
Buy DEF that is API certified. Calvin said that all Original Equipment Manufacturers (OEMs) only recommend the use of DEF that is API (American Petroleum Institute) certified by having met International Standards Organization (ISO) standard ISO-22241. Although non-certified DEF may be available at a lower price, Calvin urged producers to not take any chances and look for DEF products featuring the API logo.
According to Calvin, DEF is available from CountryMark through its branded dealers. “At this point, we don’t see any new related technology on the horizon. DEF is here to stay,” he said.