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Interlaboratory Evaluation of the Cyclone Settled Density Test for Cellulosic Loose Fill Insulation. Final Report.
Published
Author(s)
James R. Lawson
Abstract
The cyclone settled density test for cellulosic loose fill insulation was evaluated in an interlaboratory test program. Seven laboratories tested seven cellulosic loose fill insulations manufactured for the home insulation market. The participating laboratories were surveyed to evaluate the test apparatus and test methodology used at each location. It was concluded that none of the apparatus used in the program completely met the prescribed dimensional requirements for the test. However, statistical analysis of the test results showed that the repeatability coefficient of variation ranged from 2.3 to 3.7 percent with a median of 2.9 percent, and the reproduciblity coefficient of variation ranged from 4.4 to 9.9 percent with a median of 8.4 percent. The median difference in density for the materials was 28 percent when blown density was compared to settled density. This study indicated that there is reasonable assurance that test results on the same material obtained at one laboratory can be reproduced in one of the other laboratories.
Lawson, J.
(1979),
Interlaboratory Evaluation of the Cyclone Settled Density Test for Cellulosic Loose Fill Insulation. Final Report., NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=107019
(Accessed October 20, 2025)