Sponge rubber classification chart – ASTM-D 1056
| TYPE | CLASS | GRADE NUMBERPounds per square inches (PSI) required to deflect a sample 25% of its height. | SUFFIXSuffix letters are used to indicate the tests met by the compounds. In a line callout, the numbers following the suffix letters indicate test parameters or the particular conditions related to the suffix. |
|---|---|---|---|
| 1 = open-cell 2 = closed-cell |
A = non oil‑resistant(e.g. EPDM) B = oil-resistant, low oil swelling (e.g. Nitrile) C = oil-resistant, medium oil swelling (e.g. Neoprene) D = resistant to extreme temperatures (e.g. Silicone) |
0 = < 2 PSI 1 = 2-5 PSI 2 = 5-9 PSI 3 = 9-13 PSI 4 = 13-17 PSI 5 = 17-25 PSI |
A = Heat Resistance B = Compression Set C = Ozone or Weather Resistance D = Compression-Deflection Resistance E = Fluid Resistance F = Low Temperature Resistance G = Tear Resistance J = Abrasion Resistance K = Adhesion L = Water Absorption M = Flammability Resistance N = Impact Resistance P = Staining Resistance R = Resilience W = Density Z = Special Requirements |
Complete data on physical properties of products are available upon request. This data and information are intended as guides only. Performance may vary within a rubber category depending on the compounds available.
Open-cell sponge rubber
Available in EPDM, neoprene and natural rubber, open-cell sponge rubber is very efficient for sealing against air, dust and moisture. Very resilient in nature, this type of rubber is excellent for shock absorption, and sound and vibration dampening. Its high resilience also makes it ideal for sealing irregular surfaces. This product provides good thermal insulation and non‑skid traction.
Closed-cell sponge rubber
Available in EPDM, neoprene, a EPDM-neoprene-SBR blend, silicone and a PVC‑nitrile blend, closed-cell sponge rubber is impermeable to air and water, and comes in varying degrees of density and hardness. This type of rubber offers an outstanding range of performance characteristics for a host of sealing, insulation, shock-absorbing and vibration-dampening applications. Many of these products are tested to the following standards:
- UL-94, HB-F, HF-1, V0
- UL50
- SMP 205
Contact your technical advisor for more information on the best product for your application.
