ANSI/ISA

FPN) Nonincendive circuit is defined in Article 100. For further information, see Electrical Equipment for Use in Class I, Division 2 Hazardous (Classified) Locations, ANSI/ISA-S12.12-1984. 

References Guidelines for Safe and Reliable Instrumented Protective Systems, American Institute of Chemical Engineers, New York, 2007 ISA TR84.00.04, Guidelines for the Implementation of ANSI/ISA 84.00.01-2004 (IEC 61511), Instrumentation, Systems, and Automation Society, N.C., 2005 ANSI/ISA 84.00.01-2004, Functional Safety Safety Instrumented Systems for the Process Industry Sector, Instrumentation, Systems, and Automation Society, N.C., 2004 IEC 61511, Functional Safety Safety Instrumented Systems for the Process Industry Sector, International Electrotechnical Commission, Geneva, Switzerland, 2003. 

Safe Automation and ANSI/ISA 84.01-1996 served as significant technical references for the first international standard, IEC 61511, issued by the International Electrotechnical Commission (IEC). In the United States, IEC 61511 was accepted by ISA as ISA 84.00.01-2004, replacing the 1996 standard. In 2004, the European Committee for Electrotechnical Standardization (CENELEC) and the American National Standards Institute (ANSI) recognized IEC 61511 as a consensus standard for the process industry. IEC 61511 covers the complete process safety management life cycle. With its adoption, this standard serves as the primary driving force behind the work processes followed to achieve and maintain safe operation using safety instrumented systems. 

Where loss of control could lead to severe consequences, the integrity of the basic process control system and the protective safeguards must be designed, operated and maintained to a high standard. Industry standards such as ANSI/ISA-S84.01 (1996) and IEC 61508 (2000) address the issues of how to design, operate and maintain safety instrumented systems such as high temperature interlocks to achieve the necessary level of functional safety. The scope of these standards includes hardware, software, human factors and management (HSE 2000). 

Valve bodies are also standardized to mate with common piping connections flanged, butt-welded end, socket-welded end, and screwed end. Dimensional information for some of these joints and class pressure-temperature ratings are included in Sec. 10, Process Plant Piping. Control valves have their own standardized face-to-face dimensions that are governed by ANSI/ISA Standards S75.08 and S75.22. Butterfly valves are also governed by API 609 and Manufacturers Standardization Society (MSS) SP-67 and SP-68. 

The flow capacity of the transducer can be increased by adding a booster relay such as the one shown in Fig. 8-87b. The flow capacity of the booster relay is nominally 50 to 100 times that of the nozzle amplifier shown in Fig. 8-87a and makes the combined transducer/booster suitably responsive to operate pneumatic actuators. This type of transducer is stable for all sizes of load volume and produces measured accuracy (see ANSI/ISA-51.1, "Process Instrumentation Terminology, for the definition of measured accuracy) of 0.5 to 1.0 percent of span. 

ANSI/ISA-50. Fieldbus Standard for Use in Industrial Control Systems. Multiple part standard. ANSI/ISA. 

ANSI/ISA-S88.01 (1995), Batch Control Part 1 Models and Terminology. 

Instrumentation, Systems, and Automation Society, 1996, ANSI/ISA-88.01-1995 Batch Control Part 1 Models and Technology, ISA, Research Triangle Park, USA. 

ANSI/ISA SP76.00.02-2002 Modular Component Interfaces for Surface-Mount Fluid Distribution Components - Parti Elastomeric Seals, Instrumentation, Systems, and Automation Society (ISA), Compositional Analyzers Committee, 2002, www.isa.org. 

A similar approach to the IP code is used in the USA and is described in the ANSI/UL and ANSI/ISA standards but a Type Number is used instead of the two or four digit code (n, m, a, s). The basic principles are very similar. Reference 2 Article 500-4 summarises the subject and quotes the appropriate codes and standards. 

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