It is known in this industry that when it comes to emissions trucks are number one. The marine and industrial markets are actually running about 10 years behind. Trucks use an always developing system in which emits clean air from the exhaust pipe through the process of oxidation. This is created by generating various heat ranges throughout a component known as a DPF or diesel particulate filter and DOC or diesel oxidation catalyst. This process is known as an active, passive or stationary re-gen. Between 2007 and 2010, with a healthy ECM calibration update the engineers were forced to continue their quest for cleaner air. The outcome was an addition to the already technically frustrating DPF after-treatment system, an SCR catalyst. SCR or Selective Catalytic Reduction is a flow-through catalyst with a pulse width modulated injector controlled by the ECM. The fluid injected is sent to tackle most any air exhaust impurities exiting the DPF. The process is said to reduce NOx by 70-90%. All this sounds great to the environmentalist, but I can say myself as a tech… I have learned a lot and seen some interesting results of failure, but if I am not up to date on factory training I can say all is lost. As far as the maritime field goes, I feel this technology that is used everyday in the trucking industry will overwhelm the marine technicians and boat owners alike in the near future. All we can do is get ready and gear up!