Research Projects

Project at a Glance

Project Status: complete

Title: Study of in-use emissions from diesel off-road equipment

Principal Investigator / Author(s): Durbin, Thomas

Contractor: UC Riverside

Contract Number: 08-315

Research Program Area: Emissions Monitoring & Control

Topic Areas: Mobile Sources & Fuels


Gaseous and particle emissions from construction engines are an important fraction of the total air pollutants emitted into the atmosphere and are gaining increasing regulatory attention. Quantification of NOx and PM is necessary to inventory the contribution of construction equipment to atmospheric loadings, particularly for those projects in non-attainment or maintenance areas. It is also important how construction emissions might vary between different types of equipment or different types of operation. Although the development of portable emissions measurement systems (PEMS) has led to more studies of construction equipment emissions, these data are still much more limited than that available for on-road vehicles.

The goal of this research program was to obtain additional construction equipment emissions data from a test fleet of new construction equipment. An important element of this program was the use of one of the first PEMS systems to be fully compliant with the Code of Federal Requirements (CFR) for both gaseous and PM PEMS, the AVL M.O.V.E. Gas PEMS analyzer and the AVL Micro Soot Sensor (MSS). Emissions measurements were made for 27 in-use pieces of construction equipment. The equipment included 4 backhoes, 6 wheel loaders, 4 excavators, 2 scrapers (one with 2 engines), 6 bulldozers, and 4 graders. The engines ranged in model year from 2003 to 2012, in rated horsepower from 92 to 540 hp, and from 24 to 17,149 hours of operation. The emissions measurements were made on a second-by-second basis using a portable emissions measurement system (PEMS) to develop relationships between NOx and PM and other emissions and fuel use and engine brake horsepower.


For questions regarding this research project, including available data and progress status, contact: Heather Choi at (916) 322-3893

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