ASTM E659-15(2023) PDF

Overview

ASTM E659-15(2023): Standard Test Method for Autoignition Temperature of Chemicals provides a widely recognized procedure for determining the autoignition temperature (AIT) of liquid chemicals in air at atmospheric pressure. Developed by ASTM Committee E27, this standard is crucial for assessing the ignition properties of chemicals under controlled laboratory conditions. The test method is primarily intended for liquid chemicals but can also be applied, with modifications, to certain solid and gaseous chemicals.

Understanding autoignition temperature is essential for laboratory safety, process design, regulatory compliance, and fire risk assessment. It ensures safe handling, storage, and transport of chemicals by identifying temperatures at which substances may spontaneously ignite without an external ignition source.

Key Topics

• Autoignition Temperature (AIT): The minimum temperature at which a chemical ignites in air without external spark or flame under specified test conditions. Often referred to as spontaneous ignition temperature or self-ignition temperature.
• Cool-Flame Autoignition Temperature (CFT): The lowest temperature at which a visible cool flame occurs, typically at a lower temperature than hot-flame ignition.
• Test Scope and Limitations:
  • Focused on liquid chemicals, but applicable to solids that melt/vaporize or readily sublime at the test temperature and to some gases.
  • Not suitable for evaluating materials prone to exothermic decomposition or for those that do not vaporize (e.g., wood, plastics, or high-boiling-point chemicals).
  • Vessel size, material, test pressure, and oxygen concentration can significantly impact results.
• Significance: The results help in understanding thermal hazards, but laboratory AIT values may not represent minimum ignition temperatures in real-world scenarios.
• Test Methodology: Involves introducing a measured sample into a heated vessel, observing for ignition, and recording both ignition temperature and delay time.

Applications

• Chemical Process Safety: Establishing safe operating temperatures and conditions in manufacturing, blending, and storage of chemicals.
• Fire and Explosion Hazard Assessment: Providing critical input data for fire risk analysis and risk management plans in industries handling combustible chemicals.
• Regulatory Compliance: Supporting compliance with safety codes and standards by offering standardized AIT data for various chemicals.
• Transport and Storage Guidelines: Informing the packaging, storage, and transportation methods to minimize the risk of spontaneous ignition.
• Research and Development: Aiding in the development of new chemicals by identifying potential ignition hazards early in the process.

Related Standards

• ASTM D2883: Test Method for Reaction Threshold Temperature of Liquid and Solid Materials (Withdrawn 2016).
• ASTM D2155: Test Method for Determination of Fire Resistance of Aircraft Hydraulic Fluids by Autoignition Temperature (replaced by E659).
• Other ASTM E27 Standards: Covering additional tests for chemical flammability, ignitability, and hazard potential.
• International Standards: Developed in accordance with World Trade Organization (WTO) TBT Committee principles for globally recognized testing and standardization.

Keywords: autoignition temperature, spontaneous ignition, ASTM E659, chemical safety, flammability testing, fire risk assessment, hazard analysis, cool flame, laboratory standard, chemical process safety, combustible materials, ignition properties.