Overview
EN ISO 10628-2:2012 - Diagrams for the chemical and petrochemical industry, Part 2: Graphical symbols defines the standardized graphical symbols used to prepare process diagrams and engineering drawings in the chemical and petrochemical sectors. Published by CEN as an adoption of ISO 10628-2:2012, this part is a collective application of the ISO 14617 graphical-symbols series and sets a consistent notation for vessels, columns, heat exchangers, pumps, valves, filters, separators and many other process items used on P&IDs and process flow diagrams.
Key topics and technical requirements
- Scope and purpose: Standardizes graphical symbols for process diagrams in the chemical and petrochemical industry; explicitly excludes electrotechnical symbols (see IEC 60617).
- Structured symbol groups: Symbols are grouped by functional/design categories (e.g., vessels and tanks; columns with internals; heat exchangers; pumps; valves; filters; separators; agitators; piping and fittings).
- Symbol registry and numbering: Each symbol entry in the standard has an item number, ISO 14617 registration number (or provisional C/ X numbers), symbol illustration and a preferred descriptor.
- Design and modification rules: Proportions, orientation and adaptation of symbols follow ISO 81714 / IEC 81714 guidance for designing and using graphical symbols in technical documentation.
- Fallback and composition rules: If a required symbol is not in ISO 10628-2, users are directed to ISO 14617; where necessary symbols are absent in both, symbols may be created by combining ISO 14617 basic elements following ISO 81714 rules.
- Normative references: ISO 10209 (vocabulary), ISO 14617 (graphical symbols), ISO 15519-1 (diagram specification rules), ISO/IEC 81714 (symbol design).
Applications
- Creating standardized P&IDs, process flow diagrams (PFDs), engineering and plant-layout documentation.
- Producing consistent technical drawings for process design, safety studies (HAZOP), instrumentation and control schematics (excluding electrotechnical).
- Facilitating clear communication between process engineers, EPC contractors, fabrication shops, and regulatory reviewers.
Who uses this standard
- Process and chemical engineers
- P&ID drafters and CAD technicians
- Document controllers and technical authors
- Plant designers, EPC firms and operations engineers
- Safety and compliance teams preparing regulatory documentation
Related standards
- ISO 14617 (Graphical symbols for diagrams) - primary symbol source
- ISO 81714 / IEC 81714 (Design of graphical symbols)
- ISO 15519-1 (Diagrams for process industry - general rules)
- IEC 60617 (electrotechnical graphical symbols) - for electrical diagrams
Using ISO 10628-2:2012 ensures consistent, interoperable process diagrams across the chemical and petrochemical industries, improving clarity, compliance and cross-disciplinary collaboration.
