Overview
ISO 10628-1:2014 - "Diagrams for the chemical and petrochemical industry - Part 1: Specification of diagrams" defines how flow diagrams used in chemical and petrochemical plants are classified, what information they must contain, and how they should be presented. It sets drafting rules and representation conventions for flow diagrams (block diagrams, process flow diagrams, and piping & instrumentation diagrams), and serves as a collective application standard of ISO 15519. Note: ISO 10628-1:2014 does not apply to electrical engineering diagrams.
Key topics and technical requirements
- Classification of diagrams
- Distinguishes between block diagrams, process flow diagrams (PFDs) and piping & instrumentation diagrams (P&IDs) according to information needs.
- Content requirements
- Block diagrams: frame denominations, incoming/outgoing material names, main flow directions; optional flow rates and operating conditions.
- Process flow diagrams: equipment types, reference designations, material and energy flow routes and directions, material denominations and flow rates, characteristic operating conditions.
- P&IDs: detailed equipment and piping specification, identification numbers, nominal sizes/pressure ratings/piping classes, valves/fittings, and process measurement & control functions.
- Representation & drafting rules
- General presentation principles (sheet layout, title block), recommended sheet size (A1 preferred), line and arrow conventions, connections and auxiliary system representation, lettering type and size, scale and limits.
- Graphical consistency
- Equipment, valves and symbols follow ISO 10628-2; measurement and control representation follows IEC 62424.
- Normative references
Practical applications and users
- Ensures clear, unambiguous diagrams for:
- Project engineers and process designers producing PFDs and P&IDs
- CAD drafters and technical document teams preparing plant documentation
- Instrumentation & control engineers integrating measurement and control tasks
- Construction, commissioning, operation, maintenance and safety teams relying on consistent diagrams for planning and decision making
- Benefits:
- Improves multidisciplinary communication across engineering, procurement and construction
- Reduces errors in interpretation during design, construction and operations
- Facilitates compliance with company and regulatory documentation practices
Related standards
ISO 10628-1:2014 is essential for organizations producing and using flow diagrams in the chemical and petrochemical sectors to achieve consistent, industry-ready technical documentation.