Overview
EN ISO 2592:2017 / ISO 2592:2017 specifies the Cleveland open cup method for the determination of flash point and fire point of petroleum and related products. The method applies to samples with open-cup flash points between 79 °C and 400 °C (excluding fuel oils, which are commonly tested by the closed-cup method in ISO 2719). The standard was adopted by CEN as EN ISO 2592:2017 and supersedes the 2001 edition.
Key topics and technical requirements
- Scope and applicability - Open-cup flash point testing for petroleum products (79–400 °C).
- Definitions - Flash point (lowest temperature at which application of a test flame causes vapour to ignite, corrected to 101.3 kPa) and fire point (lowest temperature at which ignition is sustained for at least 5 s).
- Principle of test - Use of the Cleveland open cup apparatus; controlled heating of the test portion and periodic application of a test flame across the cup.
- Heating rates - Initial rapid warming (typically 5 °C/min to 17 °C/min), then slower constant rate (around 5 °C/min to 6 °C/min) as flash point is approached.
- Apparatus and verification - Detailed apparatus dimensions and verification procedures (Annex A and C); temperature measuring device requirements in Annex B.
- Sample handling and sampling - Guidance for sampling and subsampling, including references to ISO 3170 and ISO 3171 for sampling petroleum liquids.
- Special procedures - Annex D provides procedures to prevent surface skin formation when testing bitumens and asphalts.
- Precision and reporting - Repeatability and reproducibility criteria (note: reproducibility for flash point aligned to 18 °C to match ASTM D92); required test report content.
Practical applications
- Product classification and quality control in refineries, petrochemical plants and lubricant manufacturers.
- Safety data sheet (SDS) preparation, storage and handling risk assessments.
- Transport and storage hazard classification where open-cup flash points are required.
- Regulatory and compliance testing for petroleum-derived products.
- Validation and calibration of open-cup test equipment and laboratory competence checks.
Who should use this standard
- Industrial and commercial laboratories performing petroleum testing.
- Quality assurance and R&D teams in oil, lubricant and bitumen production.
- Test equipment manufacturers and calibration laboratories.
- Regulatory bodies and certification organizations assessing fire and flash properties.
Related standards and notes
- ISO 2719 - Closed cup flash point method (fuel oils).
- ISO 3170 / ISO 3171 - Sampling of petroleum liquids.
- Alignment with ASTM D92 is noted for precision and some procedures.
- Safety warning: the method involves hazardous materials and operations; follow appropriate lab safety and statutory requirements.
Keywords: EN ISO 2592:2017, ISO 2592:2017, Cleveland open cup, flash point, fire point, petroleum products, open cup flash point, CEN.
