An Appropriate Theoretical Model for Developing Ambient Air Quality Standard in Iran Based on Standard Setting Approaches of Different Parts of the World

Background & objectives: Environmental standards are quantitative criteria for protecting the environment from pollution and degradation. One of the solutions to improve air quality status is to use reasonable limits to prevent excessive release of airborne contaminants from their various sources. On the other hand, these standards are effective in evaluating air pollution reduction strategies. Methods: In this study, we reviewed different standard setting frameworks using a theoretical analysis. First of all, we studied the ambient air quality guidelines and standards which developed by the World Health Organization(WHO), the United States Environmental Protection Agency, the European Air Quality Management Agency, the Australian National Council for Medical and Health Research and the Canadian federal government. In addition, a framework to set the national air quality standards in Iran was proposed according to international efforts and national-specific conditions. Results: By investigating the status of standards and guidelines in some parts of the world, it was found that all of them have reasonable and rational methods for standards setting, despite some different in standard setting methods across organizations. All these standards were set on epidemiologic studies and the effects of air pollutants on human health. Except WHO, other organizations had used a quantitative risk assessment methodology to develop their own standards. Also, for developing national standards based on its guideline, WHO has recommended considering the economic, social, and health conditions. Conclusion: The results of this study indicate that for developing ambient air quality standards in Iran, a rational and scientific framework is needed.