What is the ISA-88 standard?
ISA-88 (also known as S88) is an international standard for batch process automation, developed by the International Society of Automation (ISA). The aim is to bring structure, flexibility and standardisation to the way batch processes are designed, controlled and automated.
ISA-88 makes batch control modular, reusable and scalable – and prevents vendor lock-in or ad-hoc engineering.
The standard is applied worldwide in sectors including food, pharmaceuticals, chemicals and water treatment.
🧠 What exactly does ISA-88 cover?
ISA-88 defines:
- A functional model architecture (equipment, control, procedures)
- Terminology for consistent communication
- Separation between process logic (what) and automation layer (how)
- Recipe structure that is universally applicable across multiple systems
- Foundation for Batch Control Systems software and SCADA and MES integration
🧱 Key concepts
| Concept | Description |
|---|---|
| Physical Model | Hierarchy of plant equipment: Plant → Area → Unit → Equipment Module |
| Procedural Model | The step-by-step process flow: Procedure → Unit Procedure → Operation → Phase |
| Recipe Model | Recipes are built up of parameters, equipment requirements and procedures |
| Control Module | Basic component for sensors, valves and motors with standardised functions |
| Separation of concerns | Process description is decoupled from hardware implementation |
📦 Example: Chocolate production
Suppose you want to produce batches of chocolate in different flavours:
- Physical model: Unit = mixing kettle, Module = heating jacket
- Recipe: “Dark chocolate 70%” with parameters for temperature, mixing time, ingredients
- Procedural model:
- Add ingredients
- Heat to 45°C
- Mix for 10 min
- Cool down
With ISA-88 you can flexibly adjust or reuse this on other lines or installations.
🤖 Automation & tools
- ISA-88 forms the basis for Batch Control in DCS, SCADA and MES systems
- Widely applied in tools such as Siemens Batch, Rockwell PlantPAx, ABB 800xA, DeltaV
- Essential for recipe management, CIP sequences and product changeovers
🔁 ISA-88 vs. ISA-95
| ISA-88 | ISA-95 |
|---|---|
| Focuses on batch process automation | Focuses on integration between production and business level |
| Concerns units, recipes and procedures | Concerns data exchange between MES and ERP |
| Underlies batch control | Underlies Manufacturing Operations Management |
📌 In summary
ISA-88 is the standard for the structured design and automation of batch processes. It provides a reusable architecture for procedures, recipes and equipment, making production more flexible and manageable.