!
HH-I-521F
September 4, 1980
SUPERSEDING
Fed, Spec. HH-I-521E
~U~)f 24, 1972
FEDEU L SPECIFICATION
INSULATION BLANKETS, THERML (MINEWL FIBER, FOR AMBIENT TEMPEWTURES)
This specification was approved by *O Commissioner,
Federal Supply Service, General service a
Administration, for tie use of all Federal agencies.
1. SCOPE AND CLASSIFICATION
1. 1 Stove.
Thic specification covers mineral fiber thermal incubation bknketc for use in housing and
other framed buildings at ●mbient temperatures.
While productc that comply with thio epecffication may
be used in various construction, they are adaptable primarily,
but not exclusively, to wood joist,
rafters, and stud construction.
1.2 Classification.
1.2, 1 Types and claooes.
Thermal insulation blankets shall be of the following types and classes as
specified (see 6. 2):
Type I -
Blankets with no membrane coverings.
Type II -
Blankets with a nonreflective vapor barrier membrane covering one principal face.
Class A -
Membrane with flame spre-d of 25 or less.
Class B -
Membrane with flame propagation resistance
- Critical radiant flux of O. 12 W/cm2 or greater
class c -
Membrane not r-ted for flame propagation resistance; for use in non-exposed
sppli cation only.
Type III -
Blankets with a reflective vapor barrier membrane covering one principal face,
Class A -
Membrane with fAame spread of 25 or les e,
Class B -
Membrane with flame propagation resistance
- Critical radiant flux of O. 12 W/cmz or greater.
Clans C -
Membrane not rated for flame propagation resist-ce; for US@ in non-eqosed
applications only.
1. 2.2 Sizes and thermal resistance (R) values.
Sizes and thermal resistance (R) vaiues of the bAankete
shall be in accordance with table 1, as specified (Cee 6. 2)0
TABLE L Sizee 1/ and tiermal resistance (R) valueo
Type
R valuea 2/
Width (inches) excluding flanges
Length
I, 11, III 11, 13, 19, 22
11, 15, 16, 19, 23, 24
Lengths of 100 incheo or
30, and 38
less in precut pieces,
Lengths over 100 inchee in
rolls.
~/ All sizes listed
● re not available from all manufacturer~.
For other sizes and R values consult
manufacturers.
~i Insulation blankets of the same R value, but from different manufacturers, mmy vary appreciably in
thickness [see 6, 3).
For R values other than those listed consult manufacturer,
Thermal resis-
tance (R) values apply to the mineral fiber only, so defined in 3.5. 1.
I
I
.,
[
I
FSC 5640
Downloaded from http://www.everyspec.com
