New Emissions Standards in Agriculture and Forestry

While regulations for emissions standards have become more stringent, heavy equipment manufacturers have faced increasing changes. The U.S. Environmental Protection Agency (EPA) began by implementing Tier 4 requirements on new machinery in January of 2014. These federal air emissions standards applied to diesel engines that were used for off-road equipment.


Since the Tier 4 Final laws changed in January 2014 requiring a reduction of nitrogen oxides (NOx) by 90%, manufacturers have had to deal with finding the right technology for the job. Heat from forestry equipment can increase the chances of fires, so choosing the right technology is imperative. Engines are no longer using the same fuels, and are required to use ultra-low sulfur diesel fuel (ULSD). The overall purpose of these cleaner engines is to align with state and regional clear air acts.


Tier 5 requirements will be mandatory starting January 2019. The requirements for Tier 5 are meant to further reduce particulate matter, much of which is believed to be the cause of respiratory difficulties. The ultra-fine soot that many of these engines release into the air was addressed with diesel particulate filters (DPF), which were mandated in Tier 3. However, difficulty cleaning the DPFs led many companies to change their engines to serve customers better with more efficiency and less cleaning on smaller engines.


With larger engines, the DPFs will likely be necessary as Tier 5 draws nearer. The amount of soot these engines release will make using DPFs a necessity for both stationary and mobile units. Companies are looking at making the DPFs smaller, and incorporating direct oxide reduction (DOC) and selective catalytic reduction (SCR).


Cummins and other companies will be offering new engines to meet the new timeline, while John Deere has gradually eased into the new regulations. Overall, as companies begin to meet the standards, the air quality in the U.S. and Europe should gradually improve and see less particulate matter from these types of engines.