ANSI B11.20-2017: Safety Requirements for Integrated Manufacturing Systems, the third edition of the integrated manufacturing systems standard, has been released.
Integrated manufacturing systems (IMS) incorporate multiple industrial machines that can operate independently of each other, and they involve the manufacturing, treatment, movement, or packaging of discrete parts or assemblies. Furthermore, an IMS is linked by a material handling system and is interconnected by a control system or coordinated operation.
Each integrated manufacturing system can vary in size and complexity, using different technology in need of diverse expertise and knowledge. The layout and components, comprised of the different machines, safeguarded space, hazard areas, and stop devices, are specific to the IMS. For example, an IMS can use a robot as a material handling system, and it can be comprised of several zones.
An IMS should be considered a completely new and different machine, rather than simply the sum of its parts combined. ANSI B11.20-2017 helps to assure safety within these systems by covering the design, construction, installation, maintenance, modification, and decommissioning of integrated manufacturing systems.
Whenever individual machines and equipment are incorporated into an integrated manufacturing system, new hazards and risks are introduced. However, the ANSI B11.20-2017 standard deals only with safety aspects integral to the safety-relevant interconnection of machinery and equipment. It is not intended to cover safety aspects of individual machines and equipment.
Instead, for these guidelines, users are to look to other machine-specific safety standards in the ANSI B11 series, which the ANSI B11.20-2017 standard relies on for determining risk reduction measures. In general, the ANSI B11 standards devise and propose ways to eliminate or minimize risks of the potential hazards associated with machine material processing. Standards in this series can be associated with the ISO “Type A-B-C” structure, which includes Type-A standards (basis standards), Type-B standards (generic safety standards), and Type-C standards (machinery safety standards).
Since ANSI B11.20-2017 addresses general safety elements used across a wide range of machinery, it is considered a typical Type-B document. In the past, B11 documents have made use of certain terms to describe guidelines for the safety of machinery, but, with the globalization of standards and the responding need to harmonize language, the ability to translate terms has become increasingly important.
As a result, ANSI B11.20 and some associated standards have transitioned to certain terms. For example, “safeguarding” is now “risk reduction measures/engineering controls” and “awareness devices” is now “awareness means.” In addition, the term formerly common to ANSI B11 standards, “complementary equipment,” is no longer used.
In addition to these changes, which coincide with the B11 Accredited Standards Committee’s (ASC) initiative to apply standardized processes and common language to the entire B11 series of standards, ANSI B11.20-2017 contains several other noteworthy changes. This third edition of the standard, which revises the second edition published in 2004 and reaffirmed in 2009 and 2015, elaborates on the concepts of various “zones,” introducing the term “control zone.”
Furthermore, it updates the idea of “span of control,” “zone,” “hazard zone,” and “task zone” to better harmonize with ISO 11161. A new Annex D has also been developed to detail the layout analysis process to which these concepts pertain.
In addition, ANSI B11.20-2017 expands the concept of “special mode” as any additional mode needed to operate equipment when integrated into an IMS that is not necessary when the equipment is operated independently. It also includes a new Annex E to address considerations before adding a new special mode.
ANSI B11.20-2017: Safety Requirements for Integrated Manufacturing Systems is available on the ANSI Webstore.