Evaluating Volatile Organic Compound Emissions from Cross-Laminated Timber Bonded with a Soy-Based Adhesive

Michael Yauk,Kevin Van Den Wymelenberg,Jason Stenson,Micah Donor

doi:10.3390/buildings10110191

Michael Yauk, Kevin Van Den Wymelenberg + Show 2 more

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https://doi.org/10.3390/buildings10110191

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Journal: Buildings	Publication Date: Oct 22, 2020
Citations: 7	License type: CC BY 4.0

Affiliation: University of Oregon

Abstract

Volatile organic compound (VOC) emissions from indoor sources are large determinants of the indoor air quality (IAQ) and occupant health. Cross-laminated timber (CLT) is a panelized engineered wood product often left exposed as an interior surface finish. As a certified structural building product, CLT is currently exempt from meeting VOC emission limits for composite wood products and confirming emissions through California Department of Public Health (CDPH) Standard Method testing. In this study, small chamber testing was conducted to evaluate VOC emissions from three laboratory-produced CLT samples: One bonded with a new soy-based cold-set adhesive; a second bonded with a commercially available polyurethane (PUR) adhesive; and the third assembled without adhesive using dowels. A fourth commercially-produced eight-month-old sample bonded with melamine formaldehyde (MF) adhesive was also tested. All four samples were produced with Douglas-fir. The test results for the three laboratory-produced samples demonstrated VOC emissions compliance with the reference standard. The commercially-produced and aged CLT sample bonded with MF adhesive did not meet the acceptance criterion for formaldehyde of ≤9.0 µg/m3. The estimated indoor air concentration of formaldehyde in an office with the MF sample was 54.4 µg/m3; the results for the soy, PUR, and dowel samples were all at or below 2.5 µg/m3.

Highlights

The effects of the indoor air quality (IAQ) on human health have received an increasing amount of attention in recent years [1]
To characterize Volatile organic compound (VOC) emissions from exposed Cross-laminated timber (CLT) in an indoor environment, and to compare the impacts of adhesives used in the fabrication of CLT on IAQ, small-chamber testing at an accredited facility following a standardized method was employed to test the emissions from four CLT samples with different bonding types
Target VOCs have allowable concentrations following the California Department of Public Health (CDPH) method and are one-half the Chronic Reference Exposure Limit (CREL) adopted by Cal EPA/OEHHA, except for formaldehyde, where the allowable concentration is the full CREL value of 9 μg/m3 [36,39]

Summary

Introduction

The effects of the indoor air quality (IAQ) on human health have received an increasing amount of attention in recent years [1]. Poor IAQ can adversely impact physiological markers of health, such as respiratory ailments, the risk for allergies, chronic disorders, and cancer, and has been shown to negatively affect cognition [2,3,4]. IAQ can be affected by various sources, including chemicals, gases, volatile organic compounds (VOCs), and biological particulates, such as bacteria, fungi, and pollen [1,5]. As energy efficient building strategies are becoming commonplace, a lack of attention to building IAQ can result in those energy efficient building strategies impairing

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