Hazard Control Concepts and Principles

The UK Health and Safety at Work Act 1974 defined the concept of as low as reasonable practicable (ALARP). The ALARP principle is based on reasonable practicability, which simply means that hazard controls are implemented to reduce residual risk to a reasonable level of practicality. For a risk to be considered ALARP, it must be demonstrated that the cost in reducing the residual risk further would be grossly disproportionate to the benefit gained. Therefore, a risk assessment is conducted, and a cost-benefit analysis performed to determine how far to carry the hazard control. Of course, the challenge is deciding what is practical (e.g., cost, effort, time) balanced with how much benefit of lower residual risk the hazard control brings. Unfortunately, there is no standard method to demonstrate that the hazard control trade-off will meet ALARP. However, some of the following have been successfully used ... 

While quality was formerly achieved by inspection of final products, it is accomplished now by prevention through controlling critical steps in the production processes along the agri-food chain. Hazard analysis critical control points (HACCP) represent a typical example of such a preventive approach. Although this concept was developed primarily to assure food safety, the basic principle is also applicable to assuring non-safety quality attributes such as color, flavor, and nutritional value. " This section translates the HACCP principles into a critical quality control point (CQP) concept that can be part of a system to assure food quality. 

Throughout the design of a chemical plant, issues relating to safety, economics and environmental impact must be considered. By doing so, the risks associated with the plant can be minimised before actual construction. The same principle applies whatever the scale of the process. The field of process control (Chapter 8) considers all these issues and is, indeed, informed by the type of hazard analyses described in Chapter 10. The objectives of an effective control system are the safe and economic operation of a process plant within the constraints of environmental regulations, stakeholder requirements and what is physically possible. Processes require control in the first place because they are dynamic systems, so the concepts covered in the earlier chapters of this book are central to process control (i.e. control models are based on mass, energy and momentum balances derived with respect to time). Chapter 8 focuses on the key aspects of control systems. 

The site plan concept provides an overall view of plants requiring safety inspection and establishing an early warning system for possible changes of use or process. Within this general control, detailed controls may be elaborated. If it is desired to Introduce a new plant on the site, a more detailed plant specification must then be produced. This specification must indicate the type of process to be introduced, the nature of the materials to be processed, the nature and volume of likely wastes, the main nuclear hazards, aiid a Design Safety Report, which is a statement of the principles and means for the control of safety. This information must be submitted to the Inspectorate before the licensee begins to construct the new plant on his site. 

The first and best strategy is to control the hazard at its source. Engineering controls are the best choice, unlike other controls that focus on the employee exposed to the hazard. The basic concept behind engineering controls is to the extent feasible, the work environment and the job itself should be designed to eliminate hazards or reduce exposure to hazards. Engineering controls can be simple in some cases and are based on the following principles ... 

It is highly recommended that the designers of nanotechnology facilities implement the principles ontlined in this chapter. While specific applications of those principles will vary among facilities, the overall concepts apply to a wide variety of facilities. The specific example of hazardous gas management will apply in many facilities, but beyond that, direct applications are the methods of hazard analysis and facility-level controls that were implemented in the BNC. 

This particular aspect of the Act is to be strengthened by the introduction of the Control of Substances Hazardous to Health Regulations. These far-reaching regulations will affect museums primarily in their laboratories and workshops, and their main thrust will be to introduce the concept of occupational hygiene and health principles into every workplace. 

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