Columbia's FDA "white list" materials are formulated entirely from ingredients listed in the Federal Regulation Title 21 "Food and Drugs," CFR 177.2600, "Rubber Articles Intended for Repeat Use," and have batch traceability. Please note that the FDA does not "approve" rubber compounds. It is the responsibility of the manufacturer to compound with food-grade materials from the FDA list of ingredients, as with all applications, customer(s) should test all components for the appropriateness for their specific application.

Temperature Resistance
Silicones can withstand a wider range of temperature extremes than most other elastomers, remaining stable through temperature variations from -175°F to 482° F.

Chemical Resistance
Silicones will resist water and many chemicals, including some acids, oxidizing chemicals, ammonia, and isopropyl alcohol. Concentrated acids, alkalines, and solvents should not be used with Silicones.

Mechanical Properties
Silicone rubbers have high tear (to 250 ppi) and tensile (to 1500 psi) strength, good elongation (to 1250%) and flexibility, low compression set and durometer range of 5 to 80 Shore A.

Electrical Properties
Silicones exceed all comparable material in their insulating properties as well as their versatility for electrical applications.

Silicone is a semi-organic elastomer with outstanding resistance to extremes in temperature. Specially compounded, it can provide reliable service at temperatures as low as -175°F (-115°C) to as high as 482°F (250°C). Silicone also has a good resistance to compression set. Low physical strength and abrasion resistance combined with high friction, limits silicone to static seals. Silicone is used primarily for dry heat static seals. Although it swells considerably in petroleum lubricants, this is not detrimental in most static sealing applications.

Silicone materials are available with USP class VI certification for medical grade applications. Certifications are available upon request.

Advantages: Excellent at temperature extremes, Excellent compression set resistance

Fluorocarbon (Viton®) combines resistance to a broader range of chemicals than any of the other elastomers. It constitutes the closest available approach to the universal O-ring elastomer. Although most fluorocarbon compounds become quit hard at temperatures below -4º F (-20º C), they do not easily fracture, so they are serviceable at much lower temperatures. Fluorocarbon compounds provide a continuous 437º F (225º C), high temperature capability.

Viton materials can be formulated for FDA food grade complaint level medical applications.

Advantages: Excellent chemical resistance, Excellent heat resistance, Good mechanical properties, Good compression set resistance.

Disadvantages: Fair low temperature resistance

Ethylene-propylene compounds are prepared from ethylene and propylene and usually a third monomer. These compounds are used frequently to seal phosphate ester fire resistant hydraulic fluids such as Skydrol. They are also very effective in brake systems, and for sealing hot water and steam. Ethylene-propylene compounds have good resistance to mild acids, alkalis, silicone oils and greases, ketones, and alcohols. They are not recommended for petroleum oils or diester lubricants. Ethylene-propylene has a temperature range of -67º F to 302º F (-555º C to 150º C). It is compatible with polar fluids that adversely affect other elastomers.

EPDM materials can be formulated for FDA food grade complaint level medical applications.

Advantages: Excellent weather resistance, Good low temperature flexibility, Excellent chemical resistance, Good heat resistance.

Disadvantages: Poor petroleum oil and solvent resistance.