Interlaboratory Evaluation of the ASTM E 84-77A Tunnel Test Modified by the Consumer Product Safety Commission for Cellulosic Loose Fill Insulation. Final Report.
Interlaboratory Evaluation of the ASTM E 84-77A Tunnel
Test Modified by the Consumer Product Safety Commission
for Cellulosic Loose Fill Insulation. Final Report.
Lawson, J. R.
NBSIR 79-1922; 34 p. November 1979.
Sponsor:Consumer Product Safety Commission, Bethesda, MD
Order number: PB80-128317
thermal insulation; flame spread; test methods; tunnel
tests; interlaboratory evaluation
An interlaboratory evaluation was conducted to determine
precision estimates for repeatability and
reproducibility of the American Society for Testing and
Materials (ASTM) E 84-77a tunnel test as modified by the
Consumer Product Safety Commission for cellulosic loose
fill insulation. Six laboratories participated in this
study by running tunnel tests on eight cellulosic loose
fill materials. Each laboratory was surveyed during the
project to examine its conformance with the critical
details of the test apparatus and procedure. The
results of the survey showed that none of the tunnels
completely conformed with the specifications of the
modified ASTM E 84-77a standard. The within-laboratory
coefficients of variation for repeatability for the six
fire-retardant treated cellulosic insulations ranged
from 11 to 23 percent with an average of 16 percent.
The between-laboratory coefficients of variation for
reproducibility for the same materials ranged from 31 to
41 percent with an average of 35 percent. There would
be little assurance that different laboratories would be
able to distinguish between insulations which do and
which do not comply with the CPSC mandatory level (FSC
less than or equal to 25) on a consistent basis.