What do you do if you feel that your home or office is stuffy? There are some obvious benefits to opening a window. An open window helps provide a room with air changes, which means the air within a space is exchanged. Air from an open window can replace the stagnant room air, which may be contaminated with mold, bacteria or viruses that could cause illness. The increased ventilation can help decrease carbon-dioxide levels that build over time due to room occupants’ breathing. High levels of carbon dioxide can cause fatigue and headaches. Harmful chemicals that have off-gassed from paints, furniture, or cooking can also be removed with adequate air changes from an open window.
Heating, ventilating and air conditioning (HVAC) systems are often described as the "lungs" of a building1. They can range in size from small stand-alone units serving a single room to large centrally controlled systems that serve multiple rooms in a building. HVAC systems in modern public and commercial buildings can provide heating, cooling, filtered outdoor air and humidity control to maintain comfort conditions in the building2. However, not all HVAC systems are designed to accomplish all of these functions. Some buildings rely only on natural ventilation while others lack mechanical cooling equipment (air conditioning, AC), and many function with little or no humidity control. Thermal comfort is commonly maintained with heated or cooled air that is mechanically distributed throughout the building.
