The Environmental Protection Agency (EPA) is announcing a 30- day public comment period associated with release of the document, Protocol for the Vanadium and Compounds (Inhalation) IRIS Assessment. This document communicates the rationale for conducting the Integrated Risk Information System (IRIS) assessment of vanadium and compounds (inhalation), describes screening criteria to identify relevant literature, outlines the approach for evaluating study quality, and describes the methods for dose-response analysis.