GAS MIXTURES As a leading supplier of custom specialty gas mixtures, advanced order management, sophisticated software, proven analytical instrumentation and reliable production equipment are only a few of the systems employed in the quality control and assurance that provides products to meet the demands of our customers. Custom mixtures are currently prepared by either volumetric or gravimetric techniques. GT Industries, Inc. clearly states the methods utilized to prepare custom mixtures under "Standard Specifications". The virtually unlimited possible combination of components and concentrations makes the ordering of a custom mixture a crucial process in obtaining the appropriate mixture for the user's satisfaction. Possible steps to help customers through this process are outlined below. 1. Determine the component and their concentrations. 2. Determine the particular component to be added as the balance material. Note: If the balance material has an actual requested concentration the sum of all component concentrations should equal 100%. 3. Determine the required "Make Tolerance" and "Certification Accuracy" from the standard "Mixture Tolerances" table or state your own required tolerances. 4. State the unit of measure for your component concentrations (i.e. weight percent, mole percent, or liquid volume percent). 5. Determine the desired cylinder size or indicate the desired quantity of product. Should you have difficulty in determining any of the above, contact us and we will be glad to assist you. EPA Protocols: Enviromental compliance standards for monitoring of regulated emissions. Refinery standards: Refinery Gas Standards, ASTM D3710, ASTM D2887, Hydrogen Sulfide standards, and other mixtures useful in the gasoline refinery. Petrochemical standards: An unlimited combination of components and concentrations make a comprehensive listing of calibration mixtures utilized in the laboratory and process control impossible. A partial listing of components and concentrations follows: Propylene standards: Percent to part per million Methane, Ethane, Propane, Hydrogen, Carbon Dioxide, Carbon Monoxide, Hydrogen Sulfide, Carbonyl Sulfide, Methyl Acetylene, Propadiene, Cyclopropane, and other minor components. Ethylene standards: Percent to parts per million Methane, Ethane, Oxygen, Nitrogen, Hydrogen, Carbon Dioxide, Carbon Monoxide, and other minor components. 1,3-Butadiene standards: Percent to parts per million Methane, Ethane, Ethylene, Propylene, Cis 2 Butene, Trans 2 Butene, 1 Butene, Isobutylene, 1,2 Butadiene, Methyl Acetylene, Propadiene, Vinyl Acetylene, and other minor components. Natural gas standards: GPA Reference, Calorimetric, BTU Reference, High Ethane, Natural gas processing and custom gas and liquid mixtures. Liquid standards: Percent to parts per million Benzene, Toluene, Ethyl Benzene, Xylenes, Cumene, MTBE, TAME, Styrene Alcohols, Ethers, and Ketones. ASTM D3710, ASTM D2887, ASTM D5399 and other ASTM calibration mixtures including Piston Cylinder mixtures. Sulfur standards: Percent to parts per million Hydrogen Sulfide, Carbonyl Sulfide, Methyl Mercaptan, Ethyl Mercaptan, Methyl Sulfide, Dimethyl Sulfide, Ethyl Sulfide, and Thiophene. Fugitive emission standards: Methane in Air and Hexane in Air, HRVOC mixtures. Air monitoring standards: Percent to parts per million Nitric Oxide, Sulfur Dioxide, Oxygen, Nitrogen Dioxide, and Total Hydrocarbons.