Chapter 3 Overview

This chapter provides basic information on the ways in which radon enters a home and how the indoor and outdoor environments affect its behavior.

Chapter Outline

• Chapter 3: Entry and Behavior of Radon in Indoor Air
  • How Radon Gets Indoors
  • Radon Sources
    • Radon from Radium in Soils and Bedrock
    • Building Materials
    • Water
  • Radon Transport Mechanisms
    • Aquifer & Well Water
    • Concentration Gradient Diffusion (rock & soil)
    • Emanation from Building Materials
    • Pressure Driven Airflow
  • Radon Pathways
    • Foundations
    • Other Pathways
  • Factors Affecting Indoor Radon Levels
    • Dynamic Equilibrium
    • Diurnal Cycles
    • Seasonal Variations

Chapter Learning Objectives

• Identify the primary routes of radon entry into a building
• Identify (4) mechanisms that transport radon into a building
• Identify (3) ways in which Pressure Driven Airflow draws radon into a building
• Define the concept of stack effect
• Define the concept of neutral pressure plane.  List negative pressure sources (thermal bypasses) in a building
• Explain how a spike in radon levels inside the home can occur
• List six pathways for pressure driven transport
• Identify the five common foundations common in the US and define which are pathways for pressure driven airflow
• Explain how daily and seasonal variations effect radon concentrations.
• Describe the effect of ventilation on indoor radon concentrations.
• Identify the EPA Guideline for radon in water
• Identify the primary contribution to indoor air caused by radon in water
• Identify the primary sources of radon in water.
• Identify the primary contribution to a radon in air problem due to radon in water.
• List the typical water sampling methods.
• Identify the two methods of analyzing collected water samples.
• Name at least one pro and one con for each water sampling method.