The instrument has a reasonable structure design and is convenient for operation, use and maintenance. This is a considerable improvement over systems that use analogue gauges or require flow matching and the use of graphs or tables to calculate oxygen concentrations. Germany: - 0800 5855888. Environmental Science. Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content? What is oxygenation index. The higher the Limited Oxygen Index% value the less flammable a material is. Oxygen index is a specific case of an oxidant index, which is the concentration of a given oxidant (oxygen, nitrous oxide, fluorine, etc.
A not-for-profit organization, IEEE is the world's largest technical professional organization dedicated to advancing technology for the benefit of humanity. Only measured for polymeric and plant-based materials. Benelux: - +31 88 126 8888. A dynamical systems model of the limiting oxygen index test: II. Retardancy due to char formation and addition of inert fillers: Combustion Theory and Modelling: Vol 5, No 1. The fire retardant mechanisms that we consider are non-competitive char formation and dilution by addition of an inert filler. Contact person: Prof. Ching-Iuan Su.
Element provides carbon arc testing on plastics, paints and coatings as well as other accelerated weathering testing methods to qualify new materials and determine their durability. Reprints and Corporate Permissions. Note 2: This test method and ISO 4589-2 are technically equivalent when using the gas measurement and control device described in, with direct oxygen concentration measurement. 4 (July–August 1961), pp. The limited oxygen index test is a commonly used method for assessing the flammability of materials. Standards can be obtained from appropriate standard authorities. What is limiting oxygen index in dentistry. Scope: ASTM D2863 is a method to determine the minimum concentration of oxygen in an oxygen/nitrogen mixture that will support a flaming burn in a plastic specimen. Instant access to the full article PDF.
Some sources recommend 27% as a safer threshold. The test system uses a well-known oxygen sensor and displays the result digitally, which has the advantages of accurate judgment and good reproducibility. Year of Installation - 2022. What is limiting oxygen index meaning. Plastics and cable material is tested for its LOI value at both ambient temperature and elevated temperature to understand its oxygen requirement under actual fire conditions.
The effectiveness of a gaseous agent on the fire suppression is quantified as the lowest oxygen concentration that will support combustion of a fuel, or limiting oxygen index (LOI). It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Note 1: Although this test method has been found applicable for testing some other materials, the precision of the test method has not been determined for these materials, or for specimen geometries and test conditions outside those recommended herein. PDF] Dependence of Limiting Oxygen Index of Buoyant Turbulent non-premixed Flame on Fuel | Semantic Scholar. According to the type of material being tested, there are usually 6 different sample specifications.
Oxygen concentration in ambient air is 21%, and materials with an oxygen index above 21% will exhibit some degree of self-extinguishing behaviour. In such cases, a binary answer, which covers whether the ignition occurred or did not occur at O2 concentration X, is reported. Measuring the Minimum Oxygen Concentration to Support Candle-Like Combustion of Plastics (Oxygen Index) ASTM D2863. Please note that this test description is intentionally generic in nature and aimed at providing a descriptive summary to enhance test understanding. The test results relate only to the behavior of the test specimens under the conditions of this test method and the results must not be used to infer the fire hazards of the material in other forms or under other fire conditions. This systematic approach continues until the lowest oxygen concentration is determined that will support the combustion of the material. Limiting Oxygen Index Tests and the Extinguishment Tests of Typical Flammable Liquids Fire | IEEE Conference Publication | IEEE Xplore. Need help or have a question? Engineering, Chemistry. Although devices to measure this value are commercially available, this work aims to design, fabricate, and validate an extension of these commercially available devices to a wider parameter space of interest to fundamental fire research.
The advanced LOI Limiting Oxygen Index Chamber accurately determines the relative flammability of plastics and other materials, by measuring the minimum oxygen concentration that will support combustion according to ASTM D2863 and ISO 4589 specifications. Materials with an LOI greater than the atmospheric oxygen concentration are called fire retardant materials. General Information-. A dynamical systems model of the limiting oxygen index test: II. Some limiting oxygen concentrations for diffusion flames in air diluted with nitrogen. Therefore, the results are valid only for the fire-test-exposure conditions described in this test method. Switzerland: - +41 61 686 4800. Extinguishment of Liquid Heptane and Gaseous Propane Diffusion Flames. Oxygen Index ASTM D2863.
It can not only be used as a means to identify the flammability of polymers, but also provide a powerful test tool for the laboratory to study flame retardant formulations and develop flame retardant materials. The action of the fire retardant is investigated by unfolding this bifurcation point with a suitable continuation parameter which reflects the mode of action of the additive. An analysis of the flow field and heat transfer within the device will be studied to understand the effect of sample position, forced convective flow rates, and buoyant flame entrainment. People also read lists articles that other readers of this article have read. 1088/1364-7830/5/1/304? Only when the specifications of the test specimens are the same, the test results between different materials can be compared with each other. Terence Southard with Roger Quinn, Dept. The device will be validated through a series of representative test cycles to demonstrate the capabilities of the improved design and compare with previous published data. 2 In this test method, the specimens are subjected to one or more specific sets of laboratory test conditions. Data: Oxygen Index, in percent, is calculated from the final oxygen concentrations tested. Since a laminar counterflow diffusion flame can be established in the stagnation…. SHOWING 1-10 OF 18 REFERENCES.