LOI Limiting Oxygen Index Chamber

LOI Limiting Oxygen Index Chamber – QualiLOI™ Series

QualiLOI™ Series — ASTM D2863, ISO 4589-2 & NES 714 Compliant Flammability Testing

The QualiLOI™ Series Limiting Oxygen Index (LOI) Chamber provides a precise and cost-effective method for evaluating the flammability and flame-retardant performance of combustible materials. The LOI test determines the minimum oxygen concentration, expressed as a volume percentage in a controlled oxygen and nitrogen gas mixture, required to sustain combustion of a vertically mounted specimen.

Because atmospheric air contains approximately 21% oxygen, materials with an LOI value above 21% generally tend to self-extinguish in air, while materials with an LOI below 21% can continue burning after ignition. This measurable value provides laboratories and manufacturers with a practical method for comparing the combustion behavior of plastics, polymers, rubber, electrical cables, textiles, composites, and flame-retardant materials.

The QualiLOI™ Series supports flammability testing in accordance with widely recognized standards, including ASTM D2863, ISO 4589-2, and NES 714. Its controlled oxygen concentration and test environment make the LOI chamber suitable for quality control, material development, product qualification, fire-safety research, and laboratory testing.

Paramagnetic Oxygen Sensor Technology

The QualiLOI™ PM and QualiLOI™ Auto models feature paramagnetic oxygen sensor technology for accurate and stable oxygen measurement. Unlike electrochemical oxygen sensors, paramagnetic sensors do not consume oxygen during measurement and can provide long-term measurement stability without frequent sensor replacement.

This technology helps maintain approximately 0.1% measurement accuracy, supporting consistent LOI results across extended laboratory testing programs. Reduced sensor replacement requirements can also help lower ongoing maintenance costs while improving measurement repeatability for laboratories performing frequent flammability tests.

Qualitest provides a complete QualiLOI™ Series Limiting Oxygen Index Chamber range, with configurations designed for different laboratory testing volumes, measurement requirements, and levels of automation.

Identify Flame Retardancy. Support Fire-Safety Certification.

Fire safety is a critical consideration wherever plastics, polymers, rubber, electrical cables, textiles, and composite materials are used. Industries such as automotive, aerospace, construction, electronics, transportation, and marine manufacturing require reliable methods for evaluating material combustion behavior and flame resistance.

The Limiting Oxygen Index test gives manufacturers and laboratories a quantitative measurement that can help assess the flame-retardant performance of materials. It is particularly useful for evaluating materials used in electrical insulation, cable jacketing, electronic housings, interior components, construction products, and other applications where controlled combustion performance is important.

The QualiLOI™ LOI testing chambers are designed for applications ranging from routine quality control to advanced materials research. Laboratories can evaluate flame-retardant formulations, compare polymer compositions, assess cable and plastic materials, and study combustion characteristics under controlled oxygen conditions.

LOI Testing Solutions for Different Laboratory Requirements

The Qualitest QualiLOI™ Series includes configurations for different testing needs:

• QualiLOI™ Basic — A practical LOI chamber for routine limiting oxygen index testing and laboratory quality control.

• QualiLOI™ PM — A precision LOI testing system featuring paramagnetic oxygen measurement for stable, accurate testing.

• QualiLOI™ Auto — An automated LOI testing platform designed to streamline testing procedures and improve laboratory efficiency.

From polymer development and flame-retardant additive evaluation to electrical cable testing, plastics quality control, and combustion research, the QualiLOI™ Series provides controlled and repeatable Limiting Oxygen Index testing aligned with major international flammability standards.

QualiLOI™ Limiting Oxygen Index Chamber Applications by Industry

The QualiLOI™ Limiting Oxygen Index Chamber supports controlled flammability testing across plastics, polymers, electrical materials, textiles, construction products, and other combustible materials. Its LOI testing capabilities help manufacturers, research facilities, and laboratories evaluate flame-retardant performance, combustion behavior, and material safety in accordance with applicable testing standards.

• Plastics & Polymer Manufacturing — Evaluate the flame-retardant performance of rigid plastics, engineering polymers, polyolefins, ABS, PC, PVC, polyamides, polyesters, and specialty resins using ASTM D2863 and ISO 4589-2 testing methods.

• Electric Cable & Wire Industry — Perform Limiting Oxygen Index testing on cable jacketing, electrical insulation compounds, LSZH materials, and fire-resistant cable formulations used in buildings, transportation systems, and electrical infrastructure.

• Rubber & Elastomer Industry — Assess the combustion characteristics of vulcanized rubber, thermoplastic elastomers, sealing compounds, and elastomeric components for automotive, aerospace, industrial, and transportation applications.

• Foamed Plastics & Insulation — Test the flame-retardant properties of polyurethane foams, polystyrene insulation, EPS, XPS, polyisocyanurate boards, and other foamed building-insulation materials.

• Textiles, Fibers & Apparel — Evaluate the limiting oxygen index of technical textiles, protective clothing, upholstery fabrics, carpets, awnings, and interior materials used in aerospace and transportation applications.

• Films & Flexible Packaging — Analyze combustion behavior in polymer films, multilayer laminates, agricultural films, specialty packaging materials, and other flexible polymer products.

• Building & Construction Materials — Characterize the fire-safety performance of plastic profiles, sealants, geomembranes, roofing components, architectural plastics, and other construction materials subject to fire-code requirements.

• Aerospace, Defense & Transportation — Conduct LOI flammability testing on aircraft interior materials, defense-related polymer components, and rail or automotive interior materials in accordance with NES 714 and applicable testing requirements.

• Flame-Retardant Additive Development — Compare the performance of brominated, phosphorus-based, mineral-filled, and intumescent flame-retardant systems during polymer formulation and compound development.

• Universities & Third-Party Testing Laboratories — Support polymer combustion research, materials science studies, regulatory testing, commercial certification, quality-control programs, and academic research with repeatable Limiting Oxygen Index measurements.

Why Choose Qualitest for Limiting Oxygen Index Testing?

Qualitest provides advanced flammability and materials-testing equipment for laboratories, manufacturers, research facilities, and quality-control teams worldwide. The QualiLOI™ Limiting Oxygen Index Chamber Series offers multiple configurations for different testing volumes, accuracy requirements, budgets, and automation needs.

Three-Tier LOI Testing Portfolio

The QualiLOI™ Series provides a choice of configurations ranging from the economical basic model to advanced automated systems. The QualiLOI™ Basic, QualiLOI™-PM, and QualiLOI™-Auto models allow laboratories to select an LOI testing solution based on throughput, measurement requirements, and desired automation.

The QualiLOI™-Auto features a touchscreen interface, automatic oxygen-percentage setting, and automatic cylinder-height adjustment, helping simplify routine testing procedures. Using a single LOI testing platform family can also streamline equipment procurement, operator training, maintenance, calibration, and laboratory standardization.

Paramagnetic Oxygen Sensor Technology

The QualiLOI™-PM and QualiLOI™-Auto models use paramagnetic oxygen sensor technology for stable oxygen measurement. These sensors do not consume oxygen during measurement and are designed for long-term operation without frequent sensor replacement.

With measurement accuracy of approximately 0.1%, paramagnetic sensing helps laboratories maintain consistent oxygen concentration measurements during repeated LOI tests. The reduced need for sensor replacement can also lower maintenance requirements and ongoing operating costs over the instrument's service life.

ASTM D2863, ISO 4589-2 & NES 714 Testing

The QualiLOI™ platform is designed for Limiting Oxygen Index testing in accordance with major flammability standards, including ASTM D2863, ISO 4589-2, and NES 714.

ASTM D2863 evaluates the minimum oxygen concentration required to support candle-like combustion of plastics, while ISO 4589-2 specifies an ambient-temperature oxygen-index test method for determining burning behavior. NES 714 provides requirements relevant to combustion-performance testing.

This standards-focused design helps laboratories generate consistent LOI test data for quality control, material development, product qualification, research, and regulatory testing.

Automated LOI Testing for Higher Laboratory Efficiency

The QualiLOI™-Auto simplifies routine Limiting Oxygen Index testing through automated functions. Operators can set the required oxygen percentage directly through the touchscreen interface, while the system displays the gas ratio to reduce manual calculation requirements.

Automatic quartz-cylinder height adjustment also simplifies specimen replacement and helps maintain a consistent test setup. These features can reduce setup time, minimize calculation errors, and support higher testing throughput in busy laboratories.

Flexible Specimen Testing

Qualitest LOI chambers are suitable for a broad range of combustible materials, including plastics, polymers, rubber, fibers, foamed plastics, films, textiles, wood, electrical cables, and composites.

Available sample holders accommodate both rigid supported specimens and flexible unsupported specimens, providing laboratories with greater flexibility when testing different material forms. High-temperature-resistant quartz glass cylinders provide a durable test environment for routine testing and extended laboratory programs.

Adjustable Flame Ignition

The QualiLOI™ Series includes a gas ignition system with adjustable flame length, helping maintain consistent ignition conditions between tests. Controlled ignition geometry supports repeatable combustion testing across different operators, specimens, and material batches.

The QualiLOI™-Auto also includes gas-source cutoff functionality for improved operational control and added safety during automated testing cycles.

Product Comparison Table

Cost-Effective LOI Testing with Global Support

Qualitest combines advanced LOI testing technology with competitive equipment options for laboratories of different sizes. The QualiLOI™ Basic provides an accessible solution for universities, research facilities, and smaller quality-control laboratories, while the QualiLOI™-PM and QualiLOI™-Auto offer advanced oxygen measurement and automation for laboratories with higher testing demands.

Qualitest also provides technical support, operator training, calibration assistance, and accessories, helping laboratories maintain reliable Limiting Oxygen Index testing throughout the equipment lifecycle.