JF-3 limiting oxygen index tester measuring the minimum oxygen concentration for combustion of plastics, rubber, fibers and foams.
Overview
The LOI apparatus determines the minimum oxygen concentration (volume % O in an O/N mixture) required to support candle-like flaming combustion of a polymer (plastic, rubber, fibre, foam, wood, etc.) under defined conditions. It comprises a vertical control cabinet, a transparent quartz-glass combustion column, a gas mixer, O/N flow and pressure regulation, an oxygen sensor and a digital readout. The specimen is clamped vertically in the column in an upward co-current O/N flow; after ignition at the top, burn time or burn length is observed, and through a series of oxygen concentrations the lowest O level that sustains 3 min burning or 50 mm burn length is determined. Compliant with GB/T 2406.2 (ISO 4589-2, ASTM D 2863), it is widely used for flammability grading and flame-retardant formulation in plastics, rubber, textiles, building materials and electronics.
Applications
• Road and highway engineering laboratory testing
• Construction material quality control and acceptance
• Research and teaching laboratories
• Third-party inspection and certification bodies
Features
• Robust construction suitable for both laboratory and field use
• Compliant with relevant Chinese and international testing standards
• Complete with calibration certificate and operation manual
Technical Specifications
| Item | Specification |
| Principle | oxygen-index candle-type flame combustion |
| Standards | GB/T 2406.2, ISO 4589-2, ASTM D 2863 |
| O₂ display | 0–100% O₂, direct digital readout |
| Resolution | ±0.1% |
| Overall accuracy | class 0.4 (0.2 on some models) |
| Flow range | 0–10 L/min (60–600 L/h) |
| Response time | <5 s |
| Combustion column | quartz glass, ID φ75 mm, L ~300–450 mm |
| Gas velocity in column | 40±10 mm/s |
| Mixer | glass-bead packed O₂/N₂ mixer |
| O₂/N₂ inlet pressure | >0.25 MPa |
| Pressure gauge accuracy | class 2.5 |
| Specimen | vertical centre mount in column |
| Criterion | min. O₂% sustaining 3 min or 50 mm burn |
Standards
GB/T, JTG, ASTM
Standard Delivery
• Main instrument unit
• Power cable
• Operation manual
• Spare parts kit
FAQ
Q1: What standards does the JF-3 Limiting Oxygen Index (LOI) Tester comply with?
A1: The JF-3 Limiting Oxygen Index (LOI) Tester is designed and manufactured in accordance with relevant Chinese national (GB) and transport industry (JTG) standards, as well as applicable ASTM and AASHTO international standards. A calibration certificate traceable to national standards is provided with each unit.
Q2: How often should the JF-3 Limiting Oxygen Index (LOI) Tester be calibrated?
A2: We recommend annual calibration by authorized technicians or by iRoad after-sales service center. For high-frequency laboratory use, semi-annual calibration is advised. The instrument is supplied with a factory calibration certificate.
Q3: What is the lead time and do you provide training?
A3: Standard units are usually shipped within 7-15 working days. Custom configurations may require 20-30 days. iRoad provides on-site installation, commissioning and operator training for major equipment; remote video guidance is available for standard laboratory instruments.
Overview
The LOI apparatus determines the minimum oxygen concentration (volume % O in an O/N mixture) required to support candle-like flaming combustion of a polymer (plastic, rubber, fibre, foam, wood, etc.) under defined conditions. It comprises a vertical control cabinet, a transparent quartz-glass combustion column, a gas mixer, O/N flow and pressure regulation, an oxygen sensor and a digital readout. The specimen is clamped vertically in the column in an upward co-current O/N flow; after ignition at the top, burn time or burn length is observed, and through a series of oxygen concentrations the lowest O level that sustains 3 min burning or 50 mm burn length is determined. Compliant with GB/T 2406.2 (ISO 4589-2, ASTM D 2863), it is widely used for flammability grading and flame-retardant formulation in plastics, rubber, textiles, building materials and electronics.
Applications
• Road and highway engineering laboratory testing
• Construction material quality control and acceptance
• Research and teaching laboratories
• Third-party inspection and certification bodies
Features
• Robust construction suitable for both laboratory and field use
• Compliant with relevant Chinese and international testing standards
• Complete with calibration certificate and operation manual
Technical Specifications
| Item | Specification |
| Principle | oxygen-index candle-type flame combustion |
| Standards | GB/T 2406.2, ISO 4589-2, ASTM D 2863 |
| O₂ display | 0–100% O₂, direct digital readout |
| Resolution | ±0.1% |
| Overall accuracy | class 0.4 (0.2 on some models) |
| Flow range | 0–10 L/min (60–600 L/h) |
| Response time | <5 s |
| Combustion column | quartz glass, ID φ75 mm, L ~300–450 mm |
| Gas velocity in column | 40±10 mm/s |
| Mixer | glass-bead packed O₂/N₂ mixer |
| O₂/N₂ inlet pressure | >0.25 MPa |
| Pressure gauge accuracy | class 2.5 |
| Specimen | vertical centre mount in column |
| Criterion | min. O₂% sustaining 3 min or 50 mm burn |
Standards
GB/T, JTG, ASTM
Standard Delivery
• Main instrument unit
• Power cable
• Operation manual
• Spare parts kit
FAQ
Q1: What standards does the JF-3 Limiting Oxygen Index (LOI) Tester comply with?
A1: The JF-3 Limiting Oxygen Index (LOI) Tester is designed and manufactured in accordance with relevant Chinese national (GB) and transport industry (JTG) standards, as well as applicable ASTM and AASHTO international standards. A calibration certificate traceable to national standards is provided with each unit.
Q2: How often should the JF-3 Limiting Oxygen Index (LOI) Tester be calibrated?
A2: We recommend annual calibration by authorized technicians or by iRoad after-sales service center. For high-frequency laboratory use, semi-annual calibration is advised. The instrument is supplied with a factory calibration certificate.
Q3: What is the lead time and do you provide training?
A3: Standard units are usually shipped within 7-15 working days. Custom configurations may require 20-30 days. iRoad provides on-site installation, commissioning and operator training for major equipment; remote video guidance is available for standard laboratory instruments.
