Reducing Radon in Schools: A Team Approach.

This document presents the process of radon diagnostics and mitigation in schools to help educators determine the best way to reduce elevated radon levels found in a school. The guidebook is designed to guide school leaders through the process of measuring radon levels, selecting the best mitigation strategy, and directing the efforts of a multidisciplinary team in improving the overall indoor-air quality of the school. The book focuses on using a team approach, because effective radon mitigation requires specialized knowledge in several disciplines. EPA has extensively researched two highly successful radon-control strategies: (1) mitigation using active soil depressurization (ASD); and (2) mitigation using the school's ventilation system. Chapters 1 and 2 review what radon is, why it is a concern, and the mechanisms by which it enters and accumulates in a building. Chapters 3 and 4 outline the initial investigation process, in which the condition of the ventilation system is examined to determine whether restoring the ventilation to its intended operating condition could reduce radon levels to below the Environmental Protection Agency's (EPA's) action level. The option of retesting is discussed in the fifth chapter. Chapter 6 discusses the detailed investigation phase that may be necessary if premitigation levels are too high or improving the ventilation system did not sufficiently reduce radon levels. Active subslab depressurization systems are described in chapter 7. The eighth and ninth chapters outline the process of making postmitigation measurements and discuss steps to ensure the long-term effectiveness of the mitigation strategy. Information regarding building codes and worker protection is offered in chapter 10. One table and 21 figures are included. Appendices contain a glossary and list of acronyms, a list of resource organizations, references, metric conversion factors, mitigation cost information, and two case studies based on the experience of EPA's research team. (LMI)