BISCO® 7430 Firm FR
BISCO® 7430 is a firm-grade closed-cell silicone sponge designed for flame resistant applications, with a density of 35 lb/ft³ and a compression force deflection of 14–22 psi at 25% per ASTM D1056, available in eight thicknesses from 0.063″ to 0.500″. The material has a temperature resistance range of -67°F to 400°F and meets BMS 1-60 Type 1 Grade C and FMVSS302. Tensile strength exceeds 200 psi and elongation is 250% per ASTM D412.
Key Properties
- Compression Force Deflection @ 25%: 14–22 psi (ASTM D1056)
- Tensile Strength: >200 psi (ASTM D412)
- Elongation: 250% (ASTM D412)
- Compression Set, 22 Hours @ 212°F: 35% (ASTM D1056)
- Density: 35 lb/ft³ (ASTM D1056)
- Temperature Resistance: -67°F to 400°F
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- Specifications
- Applications
- General Info
- FAQs
Physical Properties
| Property | Value | Test Method |
| Thickness | 0.063″, 0.094″, 0.125″, 0.188″, 0.25″, 0.313″, 0.375″, 0.500″ | — |
| Color | Gray | — |
| Material/Substrate | Silicone Sponge | — |
| Density | 35 lb/ft³ | ASTM D1056 |
Mechanical Properties
| Property | Value | Test Method |
| Compression Force Deflection @ 25% | 14–22 psi | ASTM D1056 |
| Compression Set, 22 Hours @ 212°F | 35% | ASTM D1056 |
| Water Absorption | <5% | ASTM D1056 |
| Tensile Strength | >200 psi | ASTM D412 |
| Elongation | 250% | ASTM D412 |
Thermal Properties
| Property | Value | Test Method |
| Temperature Resistance | -67°F to 400°F | — |
Flame & Fire Performance
| Property | Value | Test Method |
| FMVSS302 | Pass | — |
| BMS 1-60 Type 1, Grade C | Meets | — |
Environmental Performance
| Property | Value | Test Method |
| UV Resistance | Yes | — |
| Ozone Resistance | Yes | — |
Compliance
- FMVSS302 — Compliant (Pass)
- BMS 1-60 Type 1, Grade C — Compliant (Meets)
- Firm flame resistant gaskets and seals for aerospace assemblies requiring BMS 1-60 Type 1 Grade C compliance under high closure force conditions
- Automotive sealing and gasketing components requiring FMVSS302 flame compliance in a firm sponge format
- Environmental seals in enclosures and assemblies where higher mating flange loads require greater deflection resistance than medium or soft grades provide
- Flame resistant sealing in industrial and defense applications requiring a closed-cell sponge with tensile strength exceeding 200 psi
- High-closure-force flame resistant gasket applications across aerospace, automotive, and industrial markets requiring thicknesses up to 0.500″
Common industries: Aerospace, automotive, defense, industrial manufacturing.
BISCO® 7430 is a firm-grade closed-cell silicone sponge in the BISCO® flame resistant series, designed for applications requiring high closure force resistance combined with compliance to stringent aerospace and automotive flame standards.
Available in eight thicknesses from 0.063″ to 0.500″, it provides the highest CFD range and highest tensile strength (>200 psi) in the series, making it the appropriate selection for assemblies that require a firm, dimensionally stable sponge gasket under high mating flange loads. The material exhibits temperature independency and UV and ozone resistance across its service range.
Compression set is 35% at 22 hours, 212°F per ASTM D1056, and water absorption is <5% per ASTM D1056. The material passes FMVSS302 for automotive flame compliance and meets BMS 1-60 Type 1 Grade C for aerospace sealing applications. UV resistance and ozone resistance are both confirmed Yes.
Compliant with FMVSS302 and BMS 1-60 Type 1 Grade C.
What differentiates BISCO® 7430 from other grades in the BISCO® flame resistant silicone sponge series?
7430 is the firmest grade in the series with the highest CFD range of 14–22 psi at 25% and the highest tensile strength at >200 psi per ASTM D412. At the same 35 lb/ft³ density as 7330, its higher deflection resistance is the result of its closed-cell structure formulated for greater firmness. Unlike 7330, it does not carry DMS-1980 compliance, and its upper temperature resistance is 400°F versus 450°F for 7330. It is available in eight thicknesses up to 0.500", compared to twelve up to 1.00" for 7330.
Why is compression set critical for a firm flame resistant silicone sponge used in high-closure-force sealing?
Firm sponge grades are typically installed under higher flange loads than softer grades. Compression set determines whether the material maintains its geometry and sealing contact force over the service life of the assembly. In aerospace and automotive applications — where vibration, thermal cycling, and sustained mechanical loading are all present — a sponge that permanently flattens under clamp load no longer provides the gasket force needed to maintain the sealed joint. BISCO® 7430's compression set of 35% at 22 hours, 212°F per ASTM D1056 is the rated performance level for this grade within its BMS 1-60 and FMVSS302 specifications.
What is the temperature resistance range for BISCO® 7430?
The temperature resistance range is -67°F to 400°F as listed on the TDS.
Is BISCO® 7430 suitable for aerospace and automotive flame-rated environments?
Yes. BISCO® 7430 meets BMS 1-60 Type 1 Grade C for aerospace sealing applications and passes FMVSS302 for automotive flame compliance, as listed on the TDS.
How should BISCO® 7430 be specified?
Specify grade (7430SIL), thickness (from the eight available gauges), color (Gray), applicable compliance requirements (FMVSS302, BMS 1-60 Type 1 Grade C), dimensional tolerances, and finished format (sheet, slit roll, or die-cut component).
