Chapter 35 provides a robust framework for understanding air contamination mechanisms and ventilation strategies. It aligns with standards like ASHRAE Standard 62.1 to specify minimum outdoor air requirements for various building types.

At the heart of the Fundamentals volume lies (Chapter 1). The psychrometric chart, arguably the handbook’s most iconic tool, graphically represents the thermodynamic properties of moist air. The handbook not only provides the chart but also explains the underlying equations for humidity ratio, enthalpy, specific volume, and dew point. This section enables engineers to visualize and calculate air conditioning processes such as heating, cooling, dehumidification, and evaporative cooling.

This section lays the groundwork. It covers thermodynamics, heat transfer (conduction, convection, and radiation), and fluid mechanics. While many engineers learn these concepts in university, the handbook provides the specific applications relevant to buildings—such as heat transfer through building envelopes and fluid flow in pipes and ducts.

It also addresses Indoor Air Quality (IAQ), providing data on ventilation rates required to dilute contaminants and maintain a healthy environment. This section serves as the basis for ASHRAE Standard 62.1, the benchmark for ventilation design.

Note: The specific chapter numbers referenced (e.g., Chapter 1, 18) are based on the 2021 ASHRAE Handbook—Fundamentals structure, which remains generally consistent across recent editions.