US EPA

EPA announced the availability of the final report, Metabolically Derived Human Ventilation Rates: A Revised Approach Based Upon Oxygen Consumption Rates. This report provides a revised approach for calculating an individual's ventilation rate directly from their oxygen consumption rate. This approach will be used to update the ventilation rate information in the Exposure Factors Handbook, which serve as a resources for exposure assessors for calculating inhalation and other exposures.

The newly released, Metabolically Derived Human Ventilation Rates: A Revised Approach Based Upon Oxygen Consumption Rates Report is a companion book to the EPA Exposure Factors Handbook. In 1997, EPA originally published the Exposure Factors Handbook which included summaries of available statistical data on various factors that can impact an individual’s exposure to environmental contaminants. NCEA maintains the Exposure Factors Handbook and periodically updates the document using current literature and other reliable data made available through research. Many program offices within EPA, as well as state, local, and tribal health assessors, rely on the data from this handbook to conduct their exposure and risk assessments.

One important determinant of a person's exposure to contaminants in air is the ventilation rate, or the volume of air that is inhaled by an individual in a specified time period. Ventilation rate is also known as breathing or inhalation rate. This report, Metabolically Derived Human Ventilation Rates: A Revised Approach Based Upon Oxygen Consumption Rates Report presents a revised approach which calculates ventilation rates directly from an individual’s oxygen consumption rate, and applies this method to data provided from more recent sources including the 1999-2002 National Health and Nutrition Examination Survey (NHANES) and EPA's Consolidated Human Activity Database (CHAD). The revised approach was developed to replace previous approaches that were limited by their dependence on a ventilatory equivalent which in turn relied on a person’s fitness level.

This work was conducted as part of the Office of Research and Development’s Exposure Factors Program. This program provides summaries of available statistical data and recommendations for factors used to estimate human exposure to environmental contaminants. Example exposure factors include: age specific rates for drinking water consumption, food consumption, soil and dust ingestion, body weight, activity patterns, and information to estimate dermal absorption. The primary products of the program are the Exposure Factors Handbook (USEPA 1997) and the Child-Specific Exposure Factors handbook 9USEPA 2008). EPA's National Center for Environmental Assessment (NCEA) maintains the exposure factors handbooks and periodically updates those documents using current literature and other reliable data made available through research. This report on ventilation rates furthers understanding of those factors effecting human exposure.

In this report, EPA presents a revised approach in which ventilation rate is calculated directly from an individual's oxygen consumption rate.

U.S. EPA. Metabolically Derived Human Ventilation Rates: A Revised Approach Based Upon Oxygen Consumption Rates (Final Report, 2009). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/129F, 2009.