Built Environment

Indoor Environmental Quality

Indoor Environmental Quality

At its core, the built environment (office buildings, homes, public buildings such as courthouses, movie theatres and schools) is for human occupancy and our activities. As we spend more and more time indoors,we expect a better and healthier life supported by our indoor environment. It is then especially important to balance these expectations with our desire to save energy and decarbonize buildings and systems.

As building technologies such as sensors progress, we expect that our indoor space becomes more than just a place to shelter us from the elements and dangers. We expect that the indoor environment will also provide us with a “wellness” lifestyle so that we can achieve greater work productivity as well as a better life.

Real Impacts of IEQ Indicators on Human Health

It is well known that good indoor air quality as well as a comfortable thermal, acoustical and lighting environment, are some of the more obvious indicators that have been traditionally measured to evaluate the performance of the building and its systems. This is true even though their impacts or the synergy of their impacts on human health are still not entirely understood. More research needs to be done to quantify the relationships between the measured IEQ parameters and the thresholds between a ”good” and a “bad” indoor environment quality. The research should then be verified and the imbedded into ASHRAE standards such as ANSI/ASHRAE Standard 62.1, Ventilation for Acceptable Indoor Air Quality

Relations between of IEQ Indicators and Wellness

Currently, due to ongoing discussions between engineers and researchers, wellness is harder to define, particularly as a parameter to be evaluated in a building. One can argue that the lack of negative emotions such as anger and fear, or the presence of positive emotions such as happiness and trust can be, and should be, qualified as indicators of “wellness.” However, it is right to question: Is wellness as experience by building occupants all about physical, emotional and spiritual sensations? Currently, these sensations and their different levels are hard to quantify objectively. More research should be done to better quantify these emotions and how the measured IEQ parameters are interrelated to them. Finding the correlations between the IEQ parameters of building performance and the degree of wellness experienced by the building occupants should be included in ASHRAE guidelines and best practices in order to guide in the future those engineers involved with renovation and construction of buildings.

Impact of Building Systems Performances on Wellness

Lastly, but not least, ASHRAE should help to develop the methods used to monitor, validate and record these links between the building systems performances and the wellness of its occupants. These methods will help to inform the continuous improvement in buildings, and in the understanding of the role that building systems can be critical to the wellness of the building occupants.

Definitions (From ASHRAE Terminology)

Indoor environment quality: a perceived indoor experience of the building indoor environment that includes aspects of design, analysis, and operation of energy efficient, healthy, and comfortable buildings. Fields of specialization include architecture, HVAC design, thermal comfort, indoor air quality (IAQ), lighting, acoustics, and control systems.

Indoor air quality (IAQ): attributes of the respirable air inside a building (indoor climate), including gaseous composition, humidity, temperature, and contaminants

Thermal comfort: the condition of mind which expresses satisfaction with the surrounding thermal environment and is assessed by subjective evaluation. Thermal comfort is affected by heat conduction, convection, radiation, evaporative heat loss, and relative air motion.

Acoustic environment: characteristics of a room that determine the qualities of sound therein, relative to hearing.

General lighting: lighting that provides a substantially uniform level of illumination throughout an area. General lighting shall not include decorative lighting or lighting that provides a dissimilar level of illumination to serve a specialized application or feature within such area.