The measurement of volatile organic compound (VOC) emissions from building products and materials by manufacturers and testing laboratories, and the use of the test results for labeling programs, continue to expand. One issue that hinders wide acceptance for chamber product testing is the lack of a reference material to validate test chamber performance. To meet this need, the National Institute of Standards and Technology (NIST) and Virginia Tech (VT) have developed a prototype reference material that emits a single VOC similar to the emissions of a diffusion-controlled building product source with a dynamic emissions profile. The prototype material has undergone extensive testing at NIST and a pilot interlaboratory study (ILS) with four laboratories. The next development step is an evaluation of the prototype source in multiple-sized chambers of 14 laboratories in seven countries. Each laboratory was provided duplicate specimens and a test protocol. Study results identified significant issues related to the need to store the source at a subzero Celsius temperature until tested and possible inconsistencies in large chambers. For laboratories using a small chamber and meeting all the test method criteria, the results were very encouraging with relative standard deviations ranging from 5% to 10% across the laboratories. Implications: Currently, the chamber performance of laboratories conducting product VOC emissions testing is assessed through interlaboratory studies (ILS) using a source with an unknown emission rate. As a result, laboratory proficiency can only be based on the mean and standard deviation of emission rates measured by the participating ILS laboratories. A reference material with a known emission rate has the potential to provide an independent assessment of laboratory performance as well as improve the quality of interlaboratory studies. Several international laboratories with different chamber testing systems demonstrated the ability to measure the emission rate of such a reference material within an acceptable measurement uncertainty.
[1]
Steve Cox,et al.
Inter-laboratory study approach to validate the performance of a prototype reference material for product emissions testing | NIST
,
2011
.
[2]
J C Little,et al.
Diffusion-controlled reference material for VOC emissions testing: proof of concept.
,
2010,
Indoor air.
[3]
Stephen A. Wise,et al.
Standard Reference Materials: Definitions of terms and modes used at NIST for value-assignment of reference materials for chemical measurements
,
2000
.
[4]
François Maupetit,et al.
Characterization of VOC and formaldehyde emissions from a wood based panel: results from an inter-laboratory comparison.
,
2010,
Chemosphere.
[5]
W. J. Youden,et al.
Graphical Diagnosis of Interlaboratory Test Results
,
1972
.
[6]
Stephen A. Wise,et al.
Definitions of Terms and Modes Used at NIST for Value-Assignment of Reference Materials for Chemical Measurements | NIST
,
2000
.
[7]
W. Horwitz,et al.
Nomenclature of interlaboratory analytical studies (IUPAC Recommendations 1994)
,
1994
.
[8]
Cynthia Howard-Reed,et al.
Diffusion-controlled reference material for volatile organic compound emissions testing: Pilot inter
,
2011
.
[9]
Vyt Garnys.
Test Method: ASTM D5116 "Standard Guide for Small-Scale Environmental Chamber Determinations of Organic Emissions from Indoor Material/Products".
,
2010
.
[10]
Zhe Liu,et al.
Assessing the shelf-life of a prototype reference material for product emissions testing | NIST
,
2011
.