ANSI ISA-18.2:2016 pdf free download – Management of Alarm Systems for the Process Industries
1 .1 General applicability
This standard specifies general principles and processes for the lifecycle management of alarm systems based on programmable electronic controller and computer-based human-machine interface (HMI) technology for facilities in the process industries. It covers all alarms presented to the operator through the control system, which includes alarms from basic process control systems, annunciator panels, packaged systems (e.g., fire and gas systems, and emergency response systems), and safety instrumented systems. The practices in this standard are applicable to continuous, batch, and discrete processes. There can be differences in implementation to meet the specific needs based on process type. In jurisdictions where the governing authorities (e.g., national, federal, state, province, county, city) have established process safety design, process safety management, or other requirements, in addition to the requirements of this standard, these should be taken into consideration. The primary function within the alarm system is to notify operators of abnormal process conditions or equipment malfunctions and support the response. The alarm systems can include both the basic process control system (BPCS) and the safety instrumented system (SIS), each of which uses measurements of process conditions and logic to generate alarms. Figure 1 illustrates the concepts of alarm and response dataflow through the alarm system. The alarm system also includes a mechanism for communicating the alarm information to the operator via an HMI, usually a computer screen or an annunciator panel. Additional functions of the alarm system are an alarm and event log, an alarm historian, and the generation of performance metrics for the alarm system. There are external systems that can use the data from the alarm system.
1 .2.1 Operators
The functions of the operator receiving and responding to alarms are included in the scope of this standard. Management of operators is excluded from the scope of this standard.
1 .2.2 Process sensors and final control elements
The alarms from sensors and final control elements are included in the scope of this standard. Process sensors and final control elements are shown in Figure 1 to indicate alarms can be implemented in these devices. The design and management of process sensors and final control elements are excluded from the scope of this standard.
1 .2.3 Annunciator panels
The integration of independent alarm annunciator panels into an alarm system is included in the scope of this standard. The specification and design of annunciator panels is excluded from the scope of this standard. ISA-1 8.1 -1 979 (R2004), Annunciator Sequences and Specifications, provides information on alarm annunciator functions.
1 .2.4 Human machine interface
The appearance of alarms in the HMI and functions of alarm related displays are included in the scope of this standard. The design and maintenance of the HMI are excluded from this standard. ANSI/ISA-1 01 .01 -201 5, Human Machine Interfaces for Process Automation Systems, provides information on HMI.
1 .2.5 Safety instrumented systems
The alarms from safety instrumented systems are included in the scope of this standard. The safety instrumented system (SIS) is shown in Figure 1 to indicate alarms can be implemented in these devices. The design and management of safety instrumented systems are excluded from this standard. ISA-84.00.01 , Functional Safety: Safety Instrumented Systems for the Process Industry Sector – Part 1: Framework, Definitions, System, Hardware and Software Requirements, provides information on safety instrumented systems.