Contaminant Control in High-Performance Buildings Project

Net-zero energy strategies have the potential to significantly impact the indoor air quality of buildings. This project is designed to better understand how strategies to achieve net-zero energy and sustainable buildings will impact the concentrations of high-priority indoor air contaminants and to support the development of effective low-energy solutions that also improve the health of indoor environments. Specific project outcomes include improved field test methods for measuring the generation and transport of ultrafine particles and formaldehyde in buildings, reference materials and standards for product emissions testing, and performance measures for low-energy ultrafine particle controls.

Objective:  To develop test methods, reference materials, and innovative low-energy contaminant control strategies, and enable their integration into building design and retrofit guidance, standards, codes, and building material emissions labeling programs by FY2014.

What is the new technical idea?  NIST is developing the measurement science required to support strategies that maintain or improve indoor air quality (IAQ) in high-performance buildings. Changes that are being made in the design, operation and furnishing of buildings to save energy and promote sustainability (e.g., building envelope insulation and tightening, alternative ventilation approaches and equipment, and installation of “green” building materials) have the potential to significantly alter the indoor environment, with the potential to adversely affect the health and productivity of building occupants.^[1],[2] NIST is focusing on how building and system designs impact contaminants of particular concern,^[3] specifically ultrafine particles (UFP) from indoor and outdoor sources, and formaldehyde and other volatile organic compounds (VOCs) and semi-VOCs (SVOCs) from building materials and products.

NIST is also developing new measurement tools needed to support the development of low-energy control solutions that can lead to reductions in building ventilation requirements. Specifically, the use of building materials with low VOC emissions may allow energy savings by lowering outdoor air ventilation requirements. To support improved labeling of low VOC products, NIST is developing reference materials with known contaminant emissions profiles and standard residential exposure scenarios to assess the installed impact of these products. Other energy-efficient contaminant control options that are being investigated include local exhaust, enhanced filtration, and building envelope designs to reduce exposure to ultrafine particles.

NIST researchers are assessing the performance of energy-efficient ultra-fine particle control technologies.

What is the research plan?  

The research plan is addressing two primary issues: 1) the potential introduction and/or increase of contaminant levels in net-zero energy, high performance buildings; and 2) the performance of IAQ controls for reducing contaminants and building energy requirements.

The research addressing the first objective has focused on two contaminants of national importance: ultrafine particles (UFP)^[4] and formaldehyde.^[5] In FY12 NIST conducted studies to better understand the transport of ultrafine particles in buildings. In FY13, this work will be expanded to examine UFP transport issues related to natural ventilation and source control. In FY12, NIST also added the capability to measure formaldehyde in real time and at low concentrations. In FY13, this new competency will be applied to the development of formaldehyde measurement methods related to product emissions testing. In FY13, NIST will also add the capability to measure another pollutant of national importance:  SVOCs. Of particular concern, is the unintended release of SVOCs from spray polyurethane foam (SPF), which is widely used to improve the energy performance of buildings. Microchamber equipment will be installed in FY13, in part to help support the development of future SPF emissions standard test methods.

The second part of the research plan addresses the removal of high priority contaminants. In FY12, NIST assessed the effectiveness of residential kitchen exhaust hoods to remove UFP during cooking. In FY13, additional UFP control strategies to be investigated will include filtration and envelope design. UFP control performance data will also be used to develop a generalized building model for assessing different options for building design and operation. For VOCs and formaldehyde, the most effective control strategy is to reduce emissions from building products and materials. To improve the reliability of emissions testing, NIST has been developing reference materials in collaboration with Virginia Tech and EPA. Next steps include preparing the VOC reference material for mass production, conducting a workshop to address issues with the formaldehyde prototype material, and working with ASTM Subcommittee D22.05 on Indoor Air to develop a standard guide for assessing emissions measurement uncertainty. Related activities within ASTM D22.05 will also include the development of standard residential exposure scenarios, and an update of the standard guide for using carbon dioxide to evaluate IAQ and ventilation. The former will allow manufacturers and designers to estimate indoor contaminant levels associated with different product choices, while the latter will provide tools to assess IAQ and ventilation in occupied buildings.

 

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[1] Fisk, W.J. and Rosenfeld, A.H. (1997). Estimates of Improved Productivity and Health from Better Indoor Environments, Indoor Air, Vol 7:3.

[2] Committee on the Effect of Climate Change on Indoor Air Quality and Public Health (2011). Climate Change, The Indoor Environment, and Health, National Academies Press, Washington, D.C.

[3] Logue, J.M., McKone, T.E., Sherman, M.H., Singer, B.C. (2011) Hazard Assessment of Chemical Air Contaminants Measured in Residences, LBNL Report Number 3650-E.

[4] National Science and Technology Council (2008), National Nanotechnology Initiative: Strategy for Nanotechnology-Related Environmental, Health, and Safety Research, Executive Office of the President: Washington, D.C.

[5] Formaldehyde Standards for Composite Wood Products Act, signed by the President on July 7, 2010.

 

Recent Results:

Outputs:

• 8 Publications: 4 journal articles and 4 conference proceedings
• 1 Workshop: Validation of volatile organic compound emissions testing: Reference materials and analytical check standards 
• Collaborations: Virginia Tech under an MSE research grant, EPA on formaldehyde reference sources
• Staffing: 3 guest researchers (The University of Texas at Austin, Tsinghua University)

Outcomes:

• New technical expertise/equipment: Formaldehyde measurement with FTIR and HPLC
• New Tools: Development of prototype reference material for measurement of formaldehyde in chamber emissions tests
• Draft of New Standard: Draft practice to assess the uncertainty associated with chamber emissions testing in ASTM approval process

Impacts:

• Draft U.S. EPA formaldehyde regulation inclusion of chamber testing reference materials for emissions testing validation.

Standards and Codes:

Project results will provide indoor air contaminant measurement protocols and control strategies to the development and revision of several indoor air quality standards including ASHRAE 62.1 and 62.2, the indoor environmental quality (IEQ) section of ANSI/ASHRAE/USGBC/IES 189.1, and ASTM material emissions and filtration standards under committee D22 Air Quality. The project investigators have the following key leadership positions: Cindy Reed is an officer on ASTM’s D22 Executive Committee and Secretary of ASTM D22.05; Andy Persily is vice-chair and the IEQ working group chair on Standard 189.1 and a consultant to ASHRAE 62.1.