What Is ISA-95?

Industry 4.0 has introduced manufacturers to a range of new technologies. While these technologies make factory floors more efficient, they require a framework that enables systems to communicate accurately and efficiently. That’s where the ISA-95 standard helps.

This post explains the meaning of ISA-95 (also known as ANSI/ISA-95, IEC 62264, and the Purdue model for industrial control systems) and the levels of the ISA framework.

What Is ISA-95?

ISA-95 (Enterprise-Control System Integration) is an international standard for integrating enterprise and control systems. The standard allows the development of an interface for communication between various levels of a manufacturing enterprise based on the Purdue Reference Model for computer-integrated manufacturing (CIM).

In 1995, the International Society of Automation (formerly the Instrumentation, Systems, and Automation Society) and the American National Standards Institute developed ISA-95 as a successor to the ISA-88. Unfortunately, ISA-88 didn’t consider modern technologies like IoT and smart machinery.

ISA-95 specifications standardize information models and terminology, making information exchange between enterprise systems, control functions, and manufacturing operations systems frictionless.

The standard applies to all industries and processes and facilitates communication between you, suppliers, and your supply chain. It’s also immune to most technological upgrades.

“Models like ISA95, ISO OSI, and others are made to be timeless. So although the technologies used at each level changes, the model still holds true. . . . Likewise, computers changed from centralized mainframe to PC to VM and back to centralized in the cloud, but the level 4 business planning and logistics activities are still the same.”


Levels of the ISA framework

The ISA framework includes five levels (levels 0-4). Levels 0-2 include activities directly involved in manufacturing and information about materials, personnel, and equipment. The activities in these levels must also be critical for at least one of the following:

Level 3 includes activities related to manufacturing operations. For example, here is where you optimize the production process. Level 4 includes business planning and logistics decisions, such as production levels and material type.

With that in mind, here’s an overview of the five ISA-95 levels.


5 ISA-95 Levels

Level 0: Production Process

This level defines the actual physical production processes that generate the data you need to collect for your automation system.

Level 1: Sensing and Manipulation

Level 1 is closest to your factory floor and assets and includes sensors and valves. The sensors and other IoT devices you use on the factory floor collect data from manufacturing processes and transmit the data to a controller or subsystem.

Level 2: Monitoring and Supervision

This level includes the I/O subsystems, logic solvers, and DCS controllers. The systems and controllers at this level supervise and regulate the manufacturing environment. For example, an accelerometer might transmit vibration data to a programmable logic controller (PLC), which may turn off the machine when the vibrations go above or under an acceptable level.

You can apply this process to any sensor-control system combination. First, you’ll need to connect your sensors with the subsystems, logic solvers, or controllers using IIoT (Industrial Internet of Things).

Level 3: Manufacturing Operations Management

Level 3 involves workflows that help achieve production goals, such as scheduling, workload balancing, and optimizing production using a manufacturing execution system (MES).

This level involves using software solutions such as computerized maintenance management systems (CMMS), supervisory control and data acquisition (SCADA), and advanced process control (APC) to manage the various activities at your plant, including quality, production, integrity of each system’s information and span of control, emissions, and maintenance.

The workflows in level 3 aren’t limited to controlling equipment. They also direct people to take action to integrate the plant’s automatic and manual activities.

Level 4: Business Planning and Logistics

Level 4 defines administering business-related activities and plans through enterprise systems, such as an ERP system, CMMS, and CRM. These systems use data from level 3 as input to make smarter decisions. This is where you must decide how much to produce and what type of raw materials you should use.

6 Parts of the ISA-95 Standard

The ISA-95 standard is divided into six parts as follows:

  • Part 1 – Models and terminology: Part 1 includes terminologies and object models (hierarchy models, object models, operations activity models, and functional data flow models) required to interface between enterprise systems, manufacturing operations, and control functions.
  • Part 2 – Object model attributes: Part 2 defines models and tables for each object defined in part 1 and the information and the structure of that information that the ERP system should transmit to the MES.
  • Part 3 – Activity models of manufacturing operations management (MOM): Part 3 includes MOM activity models that facilitate the integration of enterprise systems with the control system. An activity model is an activity diagram that explains the sequence of steps required to form a complex process.
  • Part 4 – MOM object models and attributes: Part 4 defines object models and attributes that inform the information exchange between MES activities (as defined in part 3).
  • Part 5 – Business-to-manufacturing transactions: Part 5 describes how enterprise systems exchange information with manufacturing and automation systems at levels 3 and 4 of ISA-95. Part 5 relies on models defined in parts 1 and 2 and defines transactions related to the exchange of objects that the ISA-95 defines in parts 2, 4, and 5.
  • Part 6 – Messaging service model: Part 6 defines a messaging service model that enables applications performing business and manufacturing activities across levels 3 and 4 and within level 3 to exchange information.

Maximizing Efficiency: Use a CMMS for ISA-95 Compliance

A CMMS can help with levels 3 and 4 of the ISA-95. MaintainX, for example, can help manage and plan maintenance schedules for your assets. IoT devices can collect real-time data from assets and store it in a cloud-based CMMS like MaintainX. Moreover, MaintainX can easily integrate with your ERP for seamless data exchange.

In MaintainX, you can view advanced metrics to analyze asset performance and set alerts for assets that report data points outside desirable ranges. As a result, you can be proactive with maintenance and minimize downtime. In addition, MaintainX can help you create work orders within minutes. Technicians can use the built-in chat feature to ask questions and get answers faster.

If that sounds interesting, try MaintainX yourself to see how it can streamline maintenance.

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Caroline Eisner

Caroline Eisner is a writer and editor with experience across the profit and nonprofit sectors, government, education, and financial organizations. She has held leadership positions in K16 institutions and has led large-scale digital projects, interactive websites, and a business writing consultancy.

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