SYSTEM SPECIFIC DESIGN GUIDELINES

The specific guidance given in this Section applies in addition to the general guidance given in Section 4. 

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Example of system-specific design and installation guidelines (ARP4761, p286)... 

There are several specific regulatory documents governing the siting, design, and capacity of impoundment systems. For flammable materials, these requirements are outlined in the LNG Federal Safety Standards, 49 C.F.R. 193 (1990) and the National Fire Protection Association s Flammable and Combustible Liquids Code, NFPA 30 (1990). For toxic materials, similar design guidelines are specified in the sections of the Code of Federal Regulations (C.F.R., EPA Section 32 and EPA Section 40). 

Perhaps the first line of investigation should be a mechanical evaluation of the system to rule out causes such as instrumentation or valves. Typical investigations include an instrument check they should be tested and calibrated. Filters should be checked for channeling. Valves should be checked to determine if they are functioning properly. Filters and softeners should be checked to determine whether the specific flow rate or flux is within design guidelines. 

Compnters are widely used in analytical laboratories for instrument control, data evaluation, and data management, and are subject to all validation and verification activities. Verification and validation activities to assess compnter systems used in analytical laboratories cover all life-cycle phases, from nser Reqnirements Specifications, design, development, and manufacturing to installation and operation. In this case stndy, users of computer systems will find guidelines on ... 

In the future, systems must be able to provide aU relevant information in the user-desired form and make additional mechanisms available that reveal the consequences of a decision made during product development. The provision of information must include not only product specific data but also comprehensive information. Data covering aU topics from design guidelines and rules to design, solution, and measurement catalogs to company individual knowhow is necessary. Solutions developed for similar products need to be accessible not only in general form but in a form that takes product-related tasks and context into account. 

Specific design and instaUalion guidelines for each system (or ATA chapter) should be derived from experience, in-service data, the relevant PSSA and aircraft level requirements and objectives. As far as possible, their origin shonld be traceable (in the event of any queries on possible noncompliance) and they shonld be agreed by all parties... 

Based on Part 1 the standard provides guidelines for the specification, design, installation, operation and maintenance of Safety Instrumented Functions and related safety instmmented system as defined in lEC 61511-1. This standard has been organized so that each clause and sub clause number therein addresses the same clause number in lEC 61511-1. ... 

The measured variables listed in Table H.2 are based on the problem description, the control system specifications (Step I.A), and the general guidelines of Section 13.2. Included are several potentially useful measurements that are not needed in the control system design. 

An important distinction is made in [Bell 91] between the terms Reliability and Safety Inte ity within the context of the HSE guidelines [HSE 87]. Reliability addresses failures of a system due to hardware failures, that is, hardware failures resulting from various breakdown mechanisms that occur at random. Safety Integrity addresses both reliability and systematic failures that are due to errors that have been made at some stage in the specification, designs, construction, operation or maintenance of a system. Systematic failures are particularly important in the context of complex systems and are therefore particularly relevant to PES. 

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