|Item / Material||Temperature Range||1Chemical Resistance||Tear Resistance||2Durometer||General Information|
|Nitric Acid||Phosphoric Acid||Sodium Hypochlorite||Chlorine||Fats/Oils|
|Buna-N||-40 to 225 F||Poor||Good||Good||Poor||Excellent||Good||72||Standard Dairy & Food industry gasket. High volume equates to lowest cost. Does not hold up well to Nitric based CIP cleaners. Std. black, also white.|
|EPDM||-60 to 300 F||Good||Excellent||Good||Fair||Good||Fair||70||Good general Dairy and Food gasket. Better overall chem. resistance than Buna – not quite as good fat/oil. Std. black, also white.|
|Viton||-20 to 350 F||Excellent||Excellent||Excellent||Excellent||Excellent||Good||80||Best overall chem. resistance of common rubber gaskets. Highest price point. Std. black, also white.|
|Silicone||-80 to 450 F||Good||Fair||Good||Poor||Good||Fair||70||More common in pharmaceutical than dairy. Good overall chem. resistance. Excellent temp range. Softer durometer. Generally white or red color.|
|Teflon||-40 to 450 F||Excellent||Excellent||Excellent||Excellent||Excellent||Excellent||56||Excellent chem. & temp resistance. Very hard durometer can make sealing difficult in pipeline gasket application. Std. white, also blue.|
|TufSteel||-100 to 500 F||Excellent||Excellent||Excellent||Excellent||Excellent||Excellent||68||Passivated SS & Teflon blended in molten state (prior to molding). Highest chem. & temp resistance. Hard durometer. Highest price point. Gray color.|
|Metal Detectable||As base rubber||As base rubber||As base rubber||As base rubber||As base rubber||As base rubber||As base rubber||As base rubber||Ferrous powder mixed with rubber in molten state (prior to molding). Has same general characteristics as base rubber. Std. in Silicone & Buna. Generally red or white color.|
|Color Coded||As base rubber||As base rubber||As base rubber||As base rubber||As base rubber||As base rubber||As base rubber||As base rubber||Color code by area or date changed. Has same general characteristics as base rubber. Std. Buna. Others with minimum.|
|Teflon Envelope||-40 to 450 F||Excellent||Excellent||Excellent||Excellent||Excellent||Excellent||65-75||A “sandwich”. Teflon wrapped around Buna. Gives some better sealing than std. Teflon, but still not as good as rubber.|
|1Information from Robinson Rubber Specification Guide & Rosemount Analytical Chemical Resistance Chart. Phosphoric Acid 20%; Nitric Acid Dilute; Chlorine Wet.
2Typical – actual may vary depending on manufacturer.