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ISO-C1/2.5 Datasheet

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ISO-C1®/2.5 Polyisocyanurate Insulation

2.5 lb/ft³ (40 kg/m³) density

ISO-C1/2.5 is Dyplast Products’ 2.5 lb/ft³ polyisocyanurate rigid, closed cell, foam insulation. ISO-C1/2.5 is certified by independent laboratory to meet demanding Class 1 flame spread and smoke development requirements per ASTM E84. ISO-C1/2.5 is ideally suited for low temperature piping and refrigeration applications, and meets the demanding requirements of not only the current ASTM C591 but also CINI standards (the International Standard for Industrial Insulation). Dyplast Products offers ISO-C1/2.5 as variable-sized bunstock or as sheets and blocks with tolerances to 1/32 inch. Our extensive network of fabricators can provide special shapes for pipe, fittings, vessels, or other mechanical applications.

Polyisocyanurate exhibits the highest R-factor (insulating value) to thickness ratio of commercially available insulation, and our ISO-C1 product line provides higher R-factors and reduced thermal aging at lower temperatures. Ideal for low-temperature and cryogenic applications, ISO-C1 offers excellent performance when compared to polystyrene, polyurethane, phenolic, fiberglass, and even cellular glass alternatives. Our ISO-C1 product line is also available in 2, 3, 4, and 6 lb/ft³ densities, which each provide successively improved strength and other attributes for physically demanding applications.

ISO-C1/2.5 is produced as a continuous foam bunstock with the ability to custom size the bun in order to provide for customer fabrication to virtually any shape or size while reducing waste. For specific standard stock bun sizes contact the sales department at 1-800-433-5551 or logon to our website for ISO-C1 sizing. Our proprietary production process utilizes hydrocarbon blowing agents creating a portfolio of ISO-C1 products with physical properties superior to prior generation formulations.


ISO-C1/2.5 is designed for use where temperatures range from -297F to +300F, making it ideal for refrigeration and freezers, commercial HVAC and chill water systems, cryogenic processes such as LNG and LOX, panel insulation for transportation containers, duct and air plenum insulation, and core material for architectural and panel construction.


ISO-C1/2.5 has an exceptional WA of “zero” per ASTM D2842, the test method required by CINI (the International Standard for Industrial Insulation). It also has excellent resistance to water absorption (0.27) per ASTM C272, the test method required by ASTM C591, helping ensure long-term thermal performance. Note WA measurements per D2842 require a 96 hour immersion period, and per ASTM C272 a 24 hour period. The comparable cellular glass test per ASTM C240 requires a 2 hour immersion. Proper installation of vapor barriers can further improve performance of the complete ISO-C1/2.5 insulating system.


The International Mechanical Code defines Class 1 insulation as meeting the 25/450 flame spread/smoke development rating. ISO-C1/2.5 performs well within this range with a 25/350 rating. When comparing surface burning characteristics of alternative products, care must be taken to consider the installed insulation system as a whole, including sprinkler systems. For example, a well-designed ISO-C1 insulation system can improve overall fire/smoke performance of the polyiso insulation. On the other hand, an alternative insulation’s fire/smoke ratings may be compromised by the sealants or jacketing often recommended by suppliers. There is also the matter of insulation system integrity during a fire. ISO-C1/2.5 may be charred by flame, but maintains its integrity and continues to protect the insulated system.


High thermal insulation efficiency is achieved by infusing cells with gases having low thermal conductivity. All such rigid foam insulation (including polyurethanes and extruded polystyrene) thus lose a small amount of their insulating value over time as air displaces insulating gases. ISO-C1’s smaller, stronger cell structure and our proprietary cell-gas formulation work together to impede gas transfer across cell boundaries, thus reducing loss of thermal efficiency. It is important to note that ISO-C1/2.5’s service temperatures are normally well below 75°F, and that thermal aging is reduced considerably at lower operating temperatures. Thicker insulation, vapor barriers, and metal jacket constraints also limit gas diffusion.


Visit www.dyplast.com for easily accessible information on specifications in CSI format as well as installation, SDS, and other safety information. Relevant documents are retrievable within two clicks from our home page.