The California Air Resources Board (Cal ARB) is a part of the California Environmental Protection Agency, an organization which reports directly to the Governor's Office in the Executive Branch of California State Government. The Mission of the Cal ARB is to promote and protect public health, welfare and ecological resources through the effective and efficient reduction of air pollutants.

On July 26, 2007, the Air Resources Board (ARB) adopted the In-Use Off-Road Regulation to reduce diesel particulate matter (PM) and oxides of nitrogen (NOx) emissions from existing off-road heavy-duty diesel vehicles in California. Such vehicles are used in construction, mining, and industrial operations.

This page will provide links to regulations, articles and public comments submitted by interested parties and will be updated as new information becomes available. If you have items you would like posted on this page, contact Dick Dressler (414-298-4132).