INDOOR ENVIRONMENTAL QUALITY FAQS
WHAT ARE SOME COMMON AIRBORNE CONTAMINANTS?
Some of the most common indoor air contaminants are:
- Moisture. You may not think of this as a contaminant, but moisture can create an atmosphere for the growth and generation ofbio-aerosols such as bio-organisms and mold.
- Pollen
- Gaseous contaminants for example, ammonia, carbon monoxide and carbon dioxide.
- Volatile organic compounds (VOC)
There are guidelines for environmental emissions offered by the U.S. Environmental Protection Agency, especially on the subject of air pollution due to product emissions.
WHAT ARE SOME DESIGN STRATEGIES FOR CREATING VISUAL COMFORT?
Designing spaces for visual comfort is in part practical, in part aesthetic, and includes artificial lighting, day lighting, and the creation of visually interesting environments. There are a number of lighting strategies that you can employ to create a high quality visual environment. Some recommendations are:
- Provide lighting controls that optimize the balance between day lighting and artificial lighting.
- You can increase the perceived space brightness by lighting vertical surfaces—one idea is the use of sconces.
- Balance the quantity of light with the quality of light in all work areas, in other words carefully plan the placement of lighting fixtures.
- Control ceiling lighting glare and provide user-controlled task lighting at workstations.
- Remember lighting needs change over time, so design lighting with flexibility in mind.
Whenever possible integrate natural lighting into your plans. Studies have shown that natural lighting affects people's mood and as well as their comfort levels. So provide as much daylight as possible without impacting thermal comfort.
Overlaying all of these principles is the need for aesthetics—designing for visual interest. So, whenever possible provide a view of outdoors as well as access to outdoors. Try to include natural environments between the interior and exterior—bring a little nature to the indoors. Balance the use of such elements as scale, color, texture and pattern, as well as artwork and plants to create visual interest. Conversely, don’t be boring: avoid uniformity and avoid visual chaos—keep designs clean and simple.
What is the standard for thermal comfort?
There are a few standards for thermal comfort in buildings that have been set over the years by building and design industry organizations. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 55 presents detailed information on why building occupants complain about thermal conditions in a building. Air temperature and humidity, as you might imagine, is high on the list—but there’s a great deal more. Radiant temperature surfaces such as walls and ceilings—too hot; too cold—cause complaints, as well as floor temperature. Vertical temperature differences and drafts, causing convective heat transfer- add to the list. Secondary factors include daily and seasonal change in temperature and humidity. In addition, the age of the occupant plays a role and even the adaptability of individuals to change.
What standards address acceptable indoor air quality in buildings?
There are a few standards for thermal comfort in buildings that have been set over the years by building and design industry organizations. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 55 presents detailed information on why building occupants complain about thermal conditions in a building. Air temperature and humidity, as you might imagine, is high on the list—but there’s a great deal more. Radiant temperature surfaces such as walls and ceilings—too hot; too cold—cause complaints, as well as floor temperature. Vertical temperature differences and drafts, causing convective heat transfer- add to the list. Secondary factors include daily and seasonal change in temperature and humidity. In addition, the age of the occupant plays a role and even the adaptability of individuals to change.
What are ways to achieve acoustical comfort?
There are five goals to providing a superior acoustic environment.
- Reduce sound reverberation time—the echo factor.
- Limit airborne noise—sound transmission from space to space.
- Limit sound transmission through ceilings. Often common plenums are to blame.
- Reduce impact noise.
- Minimize background noise.
What is indoor environmental quality?
Indoor environmental quality (IEQ), a concept often overlooked in building designs of the past, has only recently become an area of focus for the design community. With the recent growth of the sustainable design movement, many factors aimed at improving the health and wellbeing of the building occupant are gaining momentum. Architects and building owners are beginning to realize that healthier and more comfortable building occupants are happier and more productive. As a result, many of today’s sustainable building designs take the issue of indoor environmental quality that includes comfort into consideration. To achieve IEQ designers focus on comfort from a thermal, acoustical and visual perspective, as well as addressing indoor air quality.