Oxygen

Linde Austria Sauerstoff 5.0 lists 99.999% purity, nitrogen ≤5 ppm and water ≤3 ppm by ideal volume fraction. Linde Switzerland's O₂ 6.0 lists 99.9999 mol.% minimum, nitrogen ≤0.5 ppm and water ≤0.5 ppm. Compare the full impurity limits and use the specified oxygen-compatible equipment and cleanliness requirements. Linde Austria, Sauerstoff 5.0 Linde Switzerland, Oxygen 5.0/6.0 Product Specification

Identity and physical properties

Industrial oxygen (O₂, CAS 7782-44-7) uses UN1072 for compressed gas and UN1073 for refrigerated liquid. Specify industrial grade and supply form for the actual process. Air Liquide, Gas Encyclopedia: Oxygen

Retain temperature, pressure and phase when using these figures. A cylinder's internal volume, its equivalent gas contents and a volume of liquid oxygen are different quantities. The physical-property table is not a cylinder fill specification, pressure setting or universal liquid-to-gas conversion. Air Liquide, Gas Encyclopedia: Oxygen.

Supply form and grade

Linde describes compressed-gas cylinders and liquid supply, with bulk deliveries and on-site air separation for higher-volume users. It also distinguishes ordinary and higher-purity production routes. Choose the supply arrangement and delivered specification together; the chemical name alone does not define pressure, vaporization capacity or impurity limits. Linde, Oxygen: Supply Modes and Purities.

Linde Austria’s Sauerstoff 5.0 also limits argon to 2 ppm and hydrocarbons and CO₂ to 0.2 ppm each, by ideal volume fraction. Linde Austria, Sauerstoff 5.0

Linde Switzerland’s MS-27414, version 6, effective 3 January 2024, also limits argon in O₂ 6.0 to 1.0 ppm and hydrocarbons, CO₂ and CO to 0.1 ppm each. Its O₂ 5.0 column has different limits. Linde Switzerland, Oxygen 5.0/6.0 Product Specification

Air Products' SDS lists 100% nominal oxygen but directs users to product specifications for exact composition. This hazard-communication entry does not establish an impurity-free supply. Air Products South Africa, Oxygen SDS 097A, revision 6, February 2026, section 3.

Cutting and welding roles

In oxyfuel cutting, the fuel/oxygen flame heats the metal, while a concentrated cutting-oxygen stream oxidizes hot metal and removes reaction products from the cut. These are distinct functions even when supplied from the same oxygen source. Linde's guide limits conventional oxyfuel cutting to carbon and cast steels and emphasizes matching tips to thickness, fuel and application. An oxygen cylinder does not make a torch suitable for every alloy or fuel. Linde, Oxy Fuel Cutting.

For setup, use the equipment manufacturer's chart with the exact torch, cutting tip, fuel and thickness. Preserve whether a specified pressure is measured at the regulator or torch and whether it is a flowing condition. These are necessary selection details rather than a universal pressure recipe; Linde's discussion itself distinguishes preheat oxygen, cutting-oxygen flow and oxygen pressure in its operating tables. A value detached from its table context cannot define a complete cutting setup. Linde, Oxy Fuel Cutting.

In laser cutting of mild and carbon steels, oxygen can be an active assist gas: oxidation supplies additional heat and the jet removes liquid iron oxide. Linde warns that simply increasing oxygen pressure can increase sideways burning, dross or cut failure. Its guidance also identifies oxygen purity as a cutting-performance variable. Determine pressure and gas requirements from the machine's material/process data rather than transferring an oxyfuel setting to a laser head. Linde, Laser Cutting with LASERLINE.

Oxygen-assisted cutting leaves an oxidized edge. Linde's industrial-laser guide notes that mild steel may instead be cut with nitrogen when that oxide layer must be avoided for subsequent painting or powder coating. This is a downstream-quality consideration, not proof that either gas is always preferable. Material, surface requirements and the supported machine process remain part of the choice. Linde, Laser for Industrial Applications.

For arc welding, oxygen's use as a controlled blend component must be distinguished from pure-oxygen delivery. Linde discusses argon/oxygen and argon/carbon-dioxide/oxygen shielding mixtures selected for particular materials and processes. Gas choice affects weld metallurgy, bead shape and penetration. That guidance does not authorize pure oxygen as a substitute for a specified shielding blend or inert TIG gas. Linde, Shielding Gases.

Oxygen-compatible equipment and cleanliness

Oxygen is an oxidizer rather than a fuel. Air Products' compressed-gas SDS states that it can cause or intensify fire and may react violently with combustible material. It requires keeping valves and fittings free of oil and grease and using equipment cleaned for oxygen service and rated for the pressure involved. Suitability for another compressed gas does not establish oxygen suitability. Air Products South Africa, Oxygen SDS 097A, revision 6, February 2026, sections 2 and 7.

Cleanliness applies to all oxygen-contact parts, not only the cylinder valve. Linde's Swiss specification warns that combustion becomes faster even with a modest increase in oxygen concentration and requires oxygen-contact components to be free of oil, grease and lubricant. Maintain the equipment supplier's specified condition during assembly and maintenance. This article supplies no solvent, flushing or oxygen-cleaning procedure: cleaning acceptance and component compatibility require the applicable equipment instructions. Linde Switzerland, Oxygen Product Specification MS-27414, version 6.

Handling and liquid-oxygen distinctions

Compressed oxygen combines pressure and fire hazards. Air Products requires secured upright containers, leak checks and suitable pressure-regulating equipment, and directs users to open valves slowly to avoid pressure shock. Follow the delivered container's instructions and applicable regional SDS; do not improvise adapters or treat an upstream pressure reading as proof of correct downstream process delivery. Air Products South Africa, Oxygen SDS 097A, revision 6, February 2026, section 7.

Refrigerated oxygen adds cryogenic burns and cold-material considerations while retaining the oxidizer hazard. Air Products' separate SDS 097B, revision 5, February 2026 requires cold-insulating gloves and eye/face protection for relevant exposure and warns against oil, grease and combustible materials. Its handling guidance addresses pressure relief and venting for cryogenic containers. Use vessel-specific transfer and storage instructions; a liquid system's vaporization and relief arrangements cannot be replaced by a compressed-cylinder setup. Air Products South Africa, Oxygen Liquid/Refrigerated SDS 097B, sections 2, 7 and 8.