Which device is required by 2007 engines to control emissions?

Which device is required by 2007 engines to control emissions?

• A. Exhaust Gas Recirculation System
• B. After Treatment Device (ATD)
• C. Diesel Oxidation Catalyst
• D. Emission Control Module

Answer: (B)

Diesel engines built to meet 2007 emissions standards rely on cleaning exhaust after combustion, so an After Treatment Device is required to reduce pollutants before the exhaust leaves the vehicle. This ATD is the broad category that covers the actual devices that treat exhaust, such as DOCs, DPFs, and SCR systems. In contrast, an Exhaust Gas Recirculation system works inside the engine to lower NOx by recirculating some exhaust back to the intake, but it isn’t the exhaust aftertreatment device the standards require. A Diesel Oxidation Catalyst is one specific type of ATD, so it fits under the broader category but the key point is that the required component is the After Treatment Device. The Emission Control Module is an electronic controller, not the device that directly treats emissions.

Diesel engines built to meet 2007 emissions standards rely on cleaning exhaust after combustion, so an After Treatment Device is required to reduce pollutants before the exhaust leaves the vehicle. This ATD is the broad category that covers the actual devices that treat exhaust, such as DOCs, DPFs, and SCR systems. In contrast, an Exhaust Gas Recirculation system works inside the engine to lower NOx by recirculating some exhaust back to the intake, but it isn’t the exhaust aftertreatment device the standards require. A Diesel Oxidation Catalyst is one specific type of ATD, so it fits under the broader category but the key point is that the required component is the After Treatment Device. The Emission Control Module is an electronic controller, not the device that directly treats emissions.