Control hierarchy

Table 1. Conceptual Levels in a Process Facility Control Hierarchy...

Batch pressure filters, 11 358-373 Batch process control hierarchy,... 

Facihties and administrative costs (F A), in technology transfer, 24 376-377 Facihties design, safety of, 21 846-852 Facihties operation, safe, 21 853—854 Facihfy control hierarchy, 20 673—676 Facility erection, nondestructive evaluation during, 17 414 Facility-siting checklist, 19 532—535t FAC scale, 10 827... 

The tool was developed using about five years of industrial hygiene data to support the logarithmic scales assigned to each control strategy. The layers of protection can be represented by the diagram shown in Fig. 16.1 and translate to levels of the traditional control hierarchy. 

Each of these appraisal schemes has both benefits and drawbacks and these are summarised in Table A4 [A-10]. Which appraisal scheme that is used is usually decided at the highest level in the human resources department of the bigger companies. In small businesses the choice may will be up to the manager concerned whether they wish to operate via traditional command and control hierarchy or whether they are customer focused with members of staff self empowered. 

To handle the complexity of the plant and to still achieve the overall goal, a control hierarchy has been developed and used for many years. This architecture gets the company policy (several weeks time resolution) and refines it to the current action to be applied on any actuator of the plant (ms-sec resolution time). The procedure is to observe the state of the plant through thousands of sensors and evaluate the next action for any resolution time. Implicit, explicit, heuristic and first principles models are used in order to generate the adequate action. The common process control architecture has four control levels. The lower level of the architecture is the basic regulatory control, this control is achieved by single decentralized loops. Most of these loops are controlled by standard PID controllers. The actuating horizon at this level is just one. 

Planning and scheduling. This module corresponds with the business part of the control hierarchy. It has a business model and based on plant data (current and past values), on external data (market data, external plant info, etc.) and using the company business goals derives a production plan for the plant. It gives capacity production values as well as quality values to the lower, optimization, level. The resolution time at this level is days or weeks. 

The relation D gives rise to either control hierarchies, in which restraint is exerted by higher members on lower members, or to taxonomic hierarchies which simply rank the members in some sort of order. 

When a site moves to an ERP system, there are issues to be resolved regarding the boundaries of data ownership. Previously, systems came under the direct control of the department which required the system (e.g., purchasing controlled the purchasing system, warehousing controlled the warehousing system). Issues such as data management were handled within the department, and the control hierarchy was clear. 

Purdue Enterprise Reference Architecture (PERA) for, 1769-1772 control hierarchy in, 1769-1771 equipment organization in, 1771-1772 safety features on, 1178 span of, 1264... 

Purchasing power, inflation and, 2395 Purdue Enterprise Reference Architecture (PERA), 506, 507, 519, 1769-1772 control hierarchy in, 1769-1771 equipment organization in, 1771-1772 and ISA/ISO standards, 1772 Purdue University, 607, 660 Purpose statements (business model), 31 Push-pull force limits, 1054-1058 PV, see Profit-volume ratio... 

Behavior-based safety places responsibilities on workers for which they may not be qualified. Although worker involvement is important, it has limitations and is not a substitute for technically competent health and safety experts reviewing both existing and future operations to insure that hazards are identified and controlled. Few workers have been trained in hazard identification, risk evaluation or methods of control (hierarchy) [p. 17]. 

Kirch, P.V., Sharp, W.D. (2005) Coral Th dating of the imposition of a ritual control hierarchy in precontact Hawaii. Science, 307,102-104. 

The Packaging Machinery Manufacturers Institute is the secretariat for the standard Safety Requirements for Packaging and Packaging-Related Converting Machinery. A revision of B 155.1 was approved by ANSI in July 2006 it replaced the version issued in 2000. In part, this is the guidance given on the use of the The Hazard Control Hierarchy, a five-step process ... 

E. Established hazard control hierarchies (e.g. personnel safety, pollution prevention)... 

Adherence to control hierarchy discussed, and suitable uniform distributions of control types such as engineering as well as administrative controls. Application of independent layers of protection matching the requirements. Identification of common mode failure. 

Control hierarchy for exposure to substances hazardous to health... 

The sequential control logic required at each level of a control hierarchy in batch plants is still largely derived manually, perhaps with the aid of some structured approach. This is a time consuming and error prone activity in which safety issues are difficult to treat formally and efficiently. To overcome these problems, Alsop et al [21] and Sanchez and Machietto [22] proposed a formal method for computer aided synthesis of sequential control logic for processes modelled as state-transition systems such as the co-ordination control of batch processes. 

The management of risk is a strategic approach to health and safety that organisations must adopt in order to control the hazards that employees, contractors, community residents and others are exposed to. It requires more than just a focus on the hazard itself. The control of hazards requires organisational and administrative processes in order to be effective. Those processes need to be in place to influence the behaviours of directors, managers, supervisors and employees so that harm does not occur. They should also be bound together by a policy and their effectiveness established by measurement, review and audit. A structure to accommodate these processes is necessary if the risks from hazards are to be controlled. Its success is demonstrated when the hazard has been eliminated. Elimination is the first step in the risk control hierarchy. 

---