Sustainable Facilities Tool

IEQ occupant surveys are a cost effective and valuable resource for identifying areas of discomfort or dissatisfaction to address during renovation projects. Occupant surveys should be unbiased and encompass all components of indoor environmental quality, including air quality, thermal and lighting comfort, and acoustical privacy. The occupants’ perspective on comfort can help identify lingering issues such as excessive noise or space cleanliness. Responses to these surveys should be the focus of any renovation project, regardless if its primary goal is IEQ related, and could save wasted energy from over-lit or over-conditioned spaces. Surveys and feedback cycles should occur periodically over the life cycle of the facility to ensure the desired quality is upheld. Explore Berkeley’s Center for the Built Environment Occupant Survey.

Occupant comfort can be optimized by providing high levels of individual or group controllability with regard to ambient air, lighting, and sound. Thermal conditions, including air temperature, humidity, and speed, should be designed to allow for personalized adjustments through integration of individual thermostat controls, localized diffusers, or operable windows. Similarly, implementing task lighting strategies at workstations creates flexibility for occupants to alter their illuminated environment. Acoustic controllability can be difficult as the distractions, such as coworker conversations, are often out of the hands of the occupant. However, providing mobility (for example laptop computers) and separate acoustic zones allow occupants to seek out ambient conditions beneficial to their current task.

The way occupants interact with and utilize the building space has a direct effect on overall IEQ as many times it is humans that introduce harmful airborne particulates or distracting acoustics. Environmental Tobacco Smoke (ETS) is a known carcinogen in humans, therefore smoking should be prohibited within the building and near any doors, windows, or air intake vents. Implementing an entryway mat or grate systems by exterior doors can further help remove dust that would otherwise be spread throughout the space simply by occupants walking around.

Consider creating an open acoustic policy outlining areas where team and spontaneous discussions are encourages and areas where privacy should be respected. Providing acoustical zoning in the space with corresponding signage reminding occupants of these courtesy policies and procedures will assist in limiting distractions arising from occupant behavior.

Studies have demonstrated likely productivity gains attributed to increased occupant comfort of 0.5 – 5% from direct improvements in the quality of the office indoor environment. These productivity gains in tasks such as typewriting, learning performance, reading speed, and word memory, correlate to $20-160 billion savings annually.¹ See the Financial Impact section.

1. Fisk, W.J,”Health and Productivity Gains from Better Indoor Environments and Their Relationship with Building Energy Efficiency.” Annual Rev. Energy Environ. 25 (2000): 537-66

Ventilation, filtration, and the associated indoor air quality affect how people function within their environment. Providing ventilation rates at or above minimum rates prescribed in current U.S. building codes and in ASHRAE Standard 60.1-2007 - Ventilation for Acceptable Indoor Air Quality has demonstrated promising impacts on increased worker productivity and reduced absenteeism. In a large office study, a 35% decrease in short term absence was associated with a doubling of ventilation rate from 25 to 50 cfm/person.¹ Increasing ventilation rates replaces contaminated indoor air with fresh air from the outdoors. This air needs to be brought to temperature and distributed, however, which may require additional energy. Discuss optimal ventilation rates at the Integrative Process table to identify strategies that reach desired goals across all aspects of the project.

1. Milton, D.K., P.M. Glencross, and M.D. Walters, "Risk of sick leave associated with outdoor air supply rate, humidification, and occupant complaints". Indoor Air, 2000. 10(4): p. 212-21.

Temperature studies have found that performance of office work tasks is maximized when air temperature is approximately between 70 °F to 73 °F, with a peak at 71°F. As indoor air temperatures fluctuate from this range, estimates put performance decreases at 0.37% and 0.43% per each degree decrease or increase, respectfully.¹ To optimize worker performance, treat indoor air temperature to remain within these ranges. Further providing thermal controls to allow workers customization of their working environment may lead to even greater performance results.

1. http://www.iaqscience.lbl.gov/performance-temp-office.html

Providing daylight access and views for occupants is important in reaching performance goals as part of the IEQ strategy. According to a study done by the Light Right Consortium, lighting designs that provided direct and indirect lighting, wallwashing, and occupant dimming controls were rated as comfortable by 91% of the occupants. In the same study, significantly fewer occupants (69-71%) reported their working space as comfortable when only 2x4 downlight troffers were provided. Daylight provides an engaging and visually stimulating work environment that can lead to significant gains in productivity.

Additional studies have demonstrated that workers with better outdoor views at their workstations, compared to baseline occupants with no outdoor views, performed 16% better in memory tests.¹

1. Heschong Mahone Group, Windows and offices: a study of office workers performance and the indoor environment. 2003, Prepared for California Energy Commission: Fair Oaks, CA.

It is no surprise that our physical and mental well-being is directly impacted by our environment: the air we breathe, the temperatures we feel, and the things we hear and see. A successful IEQ strategy is essential in creating a healthy office space that promotes occupant prosperity.

Poor indoor air quality resulting from dusts, molds, and air particulates like VOCs can lead to dizziness, skin irritations, shortness of breath, and other respiratory illnesses. These conditions can become amplified after prolonged exposure to create serious health effects, especially among the population with allergies and asthma. Estimates suggest that integrating IEQ best practices into office facilities may result in up to a 25% decrease in allergy symptoms among the 53 million allergy sufferers and 25 million asthmatics.¹

Molds, which spawn from moisture and excessive humidity in the building, release spores that when inhaled can cause inflammation in respiratory tissue or inhibit the immune system. Studies have demonstrated an 87% increase in respiratory symptoms where mold levels in chair dust were elevated.² More toxic molds can produce chemicals called mycotoxins that may lead to more serious conditions such as tremors, loss of coordination, and cell death.

1. http://www.epa.gov/iaq/2. http://www.iaqscience.lbl.gov/dampness-risks-office.html

Sick Building Syndrome (SBS) are symptoms that affect a person within the building, primarily office spaces, but improve when away from the building. SBS symptoms begin quickly and can include eye, nose, and throat irritation, headache, fatigue, and coughing. These adverse health effects could be reduced 20-50%, or by 16-37 million avoided cases of common cold or influence, with conscious IEQ strategies.¹ Regarding ventilation alone, EPA’s Building Assessment Survey and Evaluation (BASE) study found that 20-30% fewer occupants reported SBS symptoms in study spaces with ventilation rates above 20 to 25 cfm/person, compared to study spaces with lower rates between 10 to 20 cfm/person.