Indoor air pollution ranked among the top five environmental risks to public health in the U.S. Environmental Protection Agency’s 1990 report “Reducing Risk: Setting Priorities and Strategies for Environmental Protection.” Despite the efforts of EPA and other private and public groups to conduct research on indoor environmental issues and to communicate the findings of that research, many Americans don’t have a clear sense of the significant health risks of indoor pollution. They also don’t know what they can do to reduce risk for asthma, cancer and other serious diseases that exposure to indoor pollutants can cause.
Americans spend about 90% of their time indoors, where concentrations of pollutants often are much higher than those outside. Thousands of chemicals and biological pollutants are found indoors, many of which are known to have significant health effects. Impacts on human health and methods for reducing exposure to indoor air pollution and the associated risk vary by building type, use and activity. Commercial and industrial environments are typically more challenging than other types of buildings because of the processes and materials used in normal operations.
EPA challenges industry
A variety of products and materials emit indoor air pollutants, especially volatile organic compounds (VOCs).Some VOC, such as benzene, carbon tetrachloride and chlororoform, are known as suspected carcinogens and can adversely affect human health. For many years scientists have been developing methods for characterizing these emissions and, in some cases, have discovered that VOC from source surfaces can be absorbed on sink surfaces and later re-emitted. The unique characteristic of VOCs in the environment is their volatility, which makes the study of VOCs more challenging than other types of contaminants.
EPA recognizes that the products, materials and technologies used inside buildings are a potential source of indoor environmental problems. A key component for achieving building improvements is using building materials that produce low levels of any potentially harmful emissions. EPA has encouraged manufacturers of building materials to use reliable emissions-testing systems to establish consensus-based guidelines and standards to assist in evaluating the materials. The Resilient Floor Covering Institute recognized the need to develop a program of emissions testing for resilient floor coverings to meet the needs of specifiers and building owners in selecting low-VOC emitting floors.
VOC emissions research
Much of the early emissions research was done by European scientists and concentrated on measuring the total VOC (TVOC) emitted from a product and establishing a threshold for the maximum allowable emissions. However, 10 years later, these same scientists agree that measuring TVOC wasn’t a good indicator of potential health problems because of a lack of reliable health risk data on the mixtures or synergistic chemical effects. Some of the early emissions test programs established in the United States (Carpet and Rug Institute Green Label Program and the Greenguard IAQ Program) were based on TVOC emissions.
In reviewing the developments in VOC emission testing, the Resilient Floor Covering Institute concluded that future IAQ testing programs need specific and rigorous requirements to be widely accepted in the marketplace. These include a focus on:
- Individual VOC and not TVOC
- VOC emission limits established by a governmental agency and based on health risk assessments
- Testing by recognized independent laboratories, certification by an independent third party
- Transparent procedures available to the public.
These requirements for an IAQ program for hard-surface flooring suggested that it would be best to base the program on the “Standard Practice for the Testing of Volatile Organic Emissions from Various Sources Using Small-Scale Environmental Chambers.” This product-testing protocol, commonly referred to as “California Section 01350,” was developed by the California Department of Health Services IAQ research staff with input from other environmental scientists. The standard practice evaluates the acceptability of the estimated concentrations relative to Chronic Reference Exposure Level (CREL) guidelines for chronic, non-cancer exposures of the general population to airborne toxicants. CRELs are developed by the California Office of Environmental Health Hazard Assessment and are the pollutant concentrations that pose no significant health risks to individuals, including sensitive subpopulations, who are indefinitely exposed to these levels. CRELs are based solely on health considerations using the best available data in the scientific literature.
FloorScore certification program introduced
The Resilient Floor Covering Institute, in conjunction with Scientific Certification Systems (SCS), introduced the FloorScore Certification program in May 2005. It tests and certifies hard-surface flooring products for compliance with IAQ requirements developed and adopted in California. SCS is an internationally recognized third-party evaluation, testing and certification organization. A flooring product that bears the FloorScore seal has been independently certified by SCS to comply with the VOC emissions criteria of the California Section 01350 program. Before the FloorScore program was introduced, there were no emissions testing programs focusing exclusively on hard-surface flooring—an integral part of any building.
By initiating an extensive emissions-testing program of flooring materials and subsequently introducing FloorScore, the resilient flooring industry has gone far beyond any regulatory requirements in offering a voluntary certification program that allows building owners to select hard-surface flooring materials that meet specific criteria with respect to emissions of VOC. The program covers a broad range of flooring materials, including linoleum, vinyl, rubber, cork, laminate, wood and ceramic. More information on the FloorScore program including those flooring products certified can be found at www.rfci.com.
Strategies for improving IAQ
Many interactive factors affect indoor air quality, most which can be controlled by the building owner. These include the operation and maintenance of the building and HVAC systems, the occupants of the building and their activities, the building contents (including furnishings), the outdoor environment and the building fabric (interior and exterior surface and finishes). The five basic strategies a building owner has for improving indoor air quality are:
- Good HVAC system design and maintenance
- Adequate ventilation with clean air
- Filtration/cleaning of the air
- Scheduling of activities (maintenance and remodeling work)
- VOC source control
Take into account both the flooring material and the adhesive system when considering IAQ as it relates to resilient floor covering. Vinyl composition flooring is generally considered to produce low levels of VOC emissions, whereas flooring adhesives, by their very nature, tend to be high emitters. But water-based flooring adhesives can provide significant reduction in VOC emissions potential as compared to solvent-based formulations.
Managing indoor air quality during and after installation requires you to determine the application and installation conditions and the ventilation available. If water-based adhesives can’t be used, increase the ventilation rates (using clean outside air) during installation and drying to improve indoor air quality.
Floor maintenance and IAQ
It’s well known that the potential for VOC emissions from flooring maintenance can be many times greater than that from the flooring material itself when you consider routine cleaning over the life of the flooring. However, this situation is changing because resilient flooring manufacturers are offering high-performance coatings on floors to reduce the need for floor maintenance chemicals. In addition, manufacturers of floor cleaners and finishes now produce lower-VOC emitting products without sacrificing the performance characteristics.
Prepare and follow written floor maintenance procedures that detail proper use, storage and purchase of cleaning materials. Be aware that floor-care products and equipment can be potential irritants or have other IAQ effects. Purchase the safest available floor maintenance products that meet your cleaning needs. Finally, educate your maintenance staff about the proper use of floor-cleaning materials, materials storage and disposal.
Bill Freeman is a technical consultant at the Resilient Floor Covering Institute, Rockport, Me. Contact him at [email protected] and (207) 236-8181.