Description / Abstract:
This specification identifies all types of heavy layer or sound
barrier materials and their usage with sound absorbing or
dissipative materials for noise decoupling assemblies.
Material Description. Products qualified to
this specification shall be identified in two (2) parts. The first
part shall identify heavy layer sound barriers by class according
to density ranges. These heavy layer materials will be further
identified, in 1.1.4 and 1.1.5 as decoupler assemblies and/or dash
mats when used in conjunction with sound absorbing materials
identified in GMW14194 and GMW14196.
Classification. All heavy layer sound barrier
materials qualified to this specification shall be listed by
class.
Class 1 - (2.5 kg/m2 ± 0.50
kg/m²).
Class 2 - (3.5 kg/m2 ± 0.50
kg/m²).
Class 3 - (4.5 kg/m2 ± 0.50
kg/m²).
Class 4 - (5.5 kg/m2 ± 0.50
kg/m²).
Class 5 - (Barrier materials 2.0 kg/m² or
6.0 kg/m²).
Mass per unit area for Class 5 barrier materials must be
specified in math file and on print.
Some barrier materials may have densities which vary between two
(2) classes. If this is the case, the material shall fall into the
higher Class of material, (e.g, a material with density of 2.8 ±
0.3 shall be considered a Class 2 material).
All decoupler assemblies shall be identified by the proper class
of heavy layer and the specific type of sound absorbing material as
identified in GMW14194 or GMW14196.
Decoupler Identifications.
Fibrous Noise Decoupler Combinations. Material
is designated by "A"; Type refers to only those fibrous materials
outlined in GMW14194. Example designation: GMW14171 Class 2 Type
A4.
Polyurethane Foam Noise Decoupler Combinations.
"Material" is designated by "B"; Type refers to only those
materials referenced in GMW14196.