784050.1 Expanding Foam Duct Sealant
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Revision 0
Apr 10, 2001
1.0 Scope
This specification applies to a two component urethane foam packaged in a single aerosol can. The foam shall be suitable for application without the use of special tools or connections. The District's primary use of this product will be to seal electrical ducts, with and without cables in them, against the passage of water.
2.0 Material
The material shall consist of a two part urethane foam containing diphenylmethane 4,4-diisocyanate (MDI) designed for use where water and damp conditions are present. The material shall be compatible with, i.e., shall not damage, steel, fiberglass or PVC conduits and polyethylene or PVC cable insulations. When used as directed by the manufacturer the material shall have the following properties:
| Permanent Color | Light hue |
| Yield | 600 cu in/l3 fl oz can |
| Temperature Stability of Cured Foam | -40 °F to +l75 °F |
| Density | 1.87 pcf |
| Cell Structure | Over 80% closed |
| Compression Strength | 8.5 psi |
| Thermal Insulation | R Factor 8.0/inch |
| Flammability | Flame spread index: 25 Smoke density: 2l0 Class I: fire rating construction |
| Shelf Life | 9 months |
3.0 Application
The foam shall be applied with a rigid plastic actuator nozzle (dispensing tube) mounted to two tapping stems on top of the can which assure that each component is delivered in the proper proportion.