INDOOR ENVIRONMENTAL QUALITY

Indoor environmental quality (IEQ) refers to the quality of a building’s environment in relation to the health and wellbeing of those who occupy space within it. IEQ is determined by many factors, including lighting, air quality, and damp conditions. Workers are often concerned that they have symptoms or health conditions from exposures to contaminants in the buildings where they work. One reason for this concern is that their symptoms often get better when they are not in the building. While research has shown that some respiratory symptoms and illnesses can be associated with damp buildings, it is still unclear what measurements of indoor contaminants show that workers are at risk for disease. In most instances where a worker and his or her physician suspect that the building environment is causing a specific health condition, the information available from medical tests and tests of the environment is not sufficient to establish which contaminants are responsible. Despite uncertainty about what to measure and how to interpret what is measured, research shows that building-related symptoms are associated with building characteristics, including dampness, cleanliness, and ventilation characteristics.

Indoor environments are highly complex and building occupants may be exposed to a variety of contaminants (in the form of gases and particles) from office machines, cleaning products, construction activities, carpets and furnishings, perfumes, cigarette smoke, water-damaged building materials, microbial growth (fungal, mold, and bacterial), insects, and outdoor pollutants. Other factors such as indoor temperatures, relative humidity, and ventilation levels can also affect how individuals respond to the indoor environment.

Understanding the sources of indoor environmental contaminants and controlling them can often help prevent or resolve building-related worker symptoms. Practical guidance for improving and maintaining the indoor environment is available.

Workers who have persistent or worsening symptoms should seek medical evaluation to establish a diagnosis and obtain recommendations for treatment of their condition.

Indoor Environmental Quality Topic Links
Dampness and Mold in Buildings	Building Ventilation
Construction and Renovation	Chemicals and Odors

NIOSH Resources

Building Air Quality

Building Air Quality Action Plan
DHHS (NIOSH) Publication No. 98-123 (June 1998)
The Building Air Quality Action Plan is intended to be used in concert with the more comprehensive Building Air Quality: A Guide for Building Owners and Facility Managers (BAQ). (See below.) This resource meets the needs of building owners and managers who want an easy-to-understand path for taking their building from current conditions and practices to the successful institutionalization of good IEQ management practices.

Building Air Quality: A Guide for Building Owners and Facility Managers
DHHS (NIOSH) Publication No. 91-114 (December 1991)
In recognition of the need for practical indoor air quality advice for building owners and facility managers, EPA and NIOSH worked jointly to produce this written guidance on preventing, identifying, and correcting indoor air quality problems.

Health Hazard Evaluations

NIOSH conducts investigations of possible health hazards in the workplace. These investigations, called Health Hazard Evaluations (HHEs), are conducted under the authority of the Occupational Safety and Health Act of 1970 and the authority of the Mine Safety and Health Act of 1977, which authorize the Secretary of Health and Human Services, following a written request from employees, authorized representative of employees, or employers, to determine whether any substance normally found in the place of employment has potentially toxic effects in such concentrations as used or found.

Some recent HHE reports related to indoor air quality have been listed below, but for a comprehensive listing, please search the HHE Database.

NIOSHTIC-2 Search

NIOSHTIC-2 search results on Indoor Environmental Quality
NIOSHTIC-2 search results on IEQ and Mold
NIOSHTIC-2 is a searchable bibliographic database of occupational safety and health publications, documents, grant reports, and journal articles supported in whole or in part by NIOSH.