May/June 2012
Standards

New alarm management technical report up for ballot

By Ellen Fussell Policastro

A new technical report from ISA18 is up for committee ballot. The new document, ISA-TR18.2.6-2012, Alarm Systems for Batch and Discrete Processes, produced by Working Group 6, is designed to provide guidance, rationale, and examples for those with a need for understanding and applying ISA-18.2 to batch and discrete processes.

Production manufacturing is generally comprised of processes that create output, either by transforming raw materials into a new material or by generating discrete physical items. Chemical, biological, physical, or other methods can be used to convert, separate, or blend materials to produce an intermediate or final product, typically measured by weight or volume. Discrete manufacturing creates components, subassemblies, or final product measured by part count. Alarms for batch and discrete processes are often associated with additional design, implementation, and management considerations, compared to those for continuous processes. This technical report is intended to include these additional considerations.

ISA18 has several working groups producing technical reports, which are designed to augment ANSI/ISA-18.00.02-2009, Management of Alarm Systems for the Process Industries, commonly referred to as ISA-18.2. These reports will add rationale, usage guidelines, and examples in different areas of alarm management. The other five reports on the docket include:

a) WG1-Alarm Philosophy
b) WG2-Alarm Identification and Rationalization
c) WG3-Basic Alarm Design
d) WG4-Enhanced and Advanced Alarm Methods
e) WG5-Alarm Monitoring, Assessment, and Audit

The general principles and techniques described in ISA-TR18.2.6 are intended for use in the lifecycle management of an alarm system based on programmable electronic controller and computer-based human machine interface (HMI) technology. Use of this technical report should consider batch and discrete process alarms from all systems presented to the operator, which may include basic process control systems, annunciator panels, safety instrumented systems, fire and gas systems, and emergency response systems.

Manufacturing processes can use batch or continuous methodology to achieve results. Batch signifies that materials or subassemblies are held or "batched" at one or more stages during manufacturing for hold or transfer, while continuous signifies that there are no interruptions until the final product is output.

The impact of applying analysis-based process improvement may result in a reduction in batching and an increase in application of continuous methods to reduce or remove non-value-added production time. However, specific product requirements, including use of high-value, unstable, or other sensitive materials and process steps, may dictate the use of batch methodologies to achieve consistent control and desired product quality. Batching commonly creates intermediate inventory, which can require more complex inventory tracking systems.

Following the recommended guidance in this technical report will not necessarily ensure that alarm management problems will be avoided. It will, however, help to identify and address alarm specification, design, implementation, and management opportunities that are important to batch and discrete processes. It can also help minimize the generation of nuisance alarms that could complicate and frustrate operator's awareness, understanding, and response to abnormal situations.

The document will go to the committee this spring. Co-chairs Joe Alford and Bridget Fitzpatrick expect publication of this technical report sometime this summer. For more information on this and other ISA18 technical reports, visit www.isa.org/standards or contact ISA Standards Administrator Ellen Fussell Policastro at efussell@isa.org.