Kletz, P. This book describes a number of dust explosion myths — which together cover the main source of dust explosion hazards — the reasons they exist and the corresponding scientific and engineering facts that mitigate these circumstances.
Kletz Kletz, T. Inherent safety in offshore oil and gas activities: a review of the present status and future directions. Journal of Loss Prevention in the Process Industries The philosophy has become an integral part of process design and process safety for Taylor and Francis, Washington D. Case histories illustrate what went wrong and why it went wrong, and then guide readers in how to avoid similar tragedies and learn without having to experience the loss incurred by others.
His ideas were developed from nearly 40 years working in the chemical industry. When he retired from the field, he shared his experience and ideas widely in more than 15 books.
Topics covered in this book include inherent safety, safety studies, human factors and design. More recently, similar requirements have been proposed at the U. Since the concept of inherently safer design applies globally, with its origins in the United Kingdom, the book will apply globally. The new edition builds on the same philosophy as the first two editions, but further clarifies the concept with recent research, practitioner observations, added examples and industry methods, and discussions of security and regulatory issues.
It emphasizes the role. Download ». Updated throughout and expanded, this sixth edition is the ultimate resource of experienced-based analysis and guidance for safety and loss prevention professionals. Kletz, P. This book describes a number of dust explosion myths — which together cover the main source of dust explosion hazards — the reasons they exist and the corresponding scientific and engineering facts that mitigate these circumstances.
Kletz Kletz, T. Inherent safety in offshore oil and gas activities: a review of the present status and future directions. Journal of Loss Prevention in the Process Industries The philosophy has become an integral part of process design and process safety for Taylor and Francis, Washington D. Reactivity data, including potential for ignition or explosion e. Corrosivity data, including effects on metals, building materials, and organic tissues f.
Identified incompatibilities and dangerous contaminants g. Thermal data heat of reaction, heat of combustion. Stability and reactivity: conditions that cause instability, known incompatible materials, hazardous decomposition products.
Toxicological information: acute effects, LD50 data, chronic effects, carcinogenicity, teratogenicity, mutagenicity. Transport information: shipping information required by the U. Department of Transport as well as other international bodies. Regulatory information: U. Additional information: date of creation and revisions, legal disclaimers. Typical material characteristic Property Characteristics General Properties Boiling point Vapor pressure Freezing point Molecular weight Critical pressure and temperature Electrical conductivity Fluid density and viscosity Thermal properties enthalpy, specific heat, heat of mixing Reactivity Reactivity with water or air Potential for sudden violent reaction Sensitivity to mechanical or thermal shock Polymerization Compatibility with materials of construction and other process materials Flammability Flash point Autoignition temperature Flammability limits Self -heating Minimum ignition energy Toxicity Threshold limit values Emergency exposure limits Lethal concentration Lethal dose Exposure Effects Stability Thermal stability Chemical stability Shelf life Products of decomposition This design guideline is believed to be as accurate as possible, but are very general and not for specific design cases.
Substitution: of the processing route with one using less hazardous material or substitution of toxic process materials with nontoxic or less toxic materials. Replacement of volatile organic solvents with aqueous systems or less hazardous organic materials improves safety of many processing operations and final products.
Containment: sound design of equipment and piping, to avoid leaks. Prevention of releases: by process and equipment design, operating procedures and design of disposal systems.
Ventilation: use open structures or provide adequate ventilation systems. Disposal: provision of effective vent stacks to disperse material vented from pressure relief devices or use of vent scrubbers.
Collection and treatment of sewer and runoff waters and liquids collected from relief systems. Emergency equipment and procedures: automated shutdown systems, escape routes, rescue equipment, respirators, antidotes if appropriate , safety showers, eye baths, emergency services. Fire and Gas Protection Fire protection systems are expected to meet a combination of purposes. Designing a fire protection system requires knowing the purposes it must serve.
To prevent the fire accidents, the performance equipment design should be planned very well. Basically the system consists of field-mounted detection equipment and manual alarm stations, a system logic unit for processing of incoming signals, alarm and HMI units. The fire and gas detection systems shall automatically start active fire protection systems as appropriate, initiate shutdowns and alarm personnel both audibly and visually throughout platform of a fire incipient or confirmed condition or a hydrocarbon gas or a toxic gas release.
The Guide presents a process for performance-based design centeredaround the following major steps: 1. Defining the Project Scope 2. Identifying the Fire Safety Goals 3. Defining Stakeholder and Design Objectives 4. Developing Performance Criteria 5.
Developing Design Fire Scenarios 6. Developing Trial Designs 7. Evaluating Trial Designs 8. Selecting the Final Design This design guideline is believed to be as accurate as possible, but are very general and not for specific design cases.
Review possible fire scenarios: what fuels are involved, where the fire might start, how fast it might spread. Where the rapid spread of the fire is likely, automatic actuation of protective systems should be specified. When a flame detector is used, a dual sensor IR-IR or UV-IR flame detector is preferred to reduce the potential for false alarm and is required when the detector will automatically activate a suppression system.
IR flame detectors are preferred for hydrocarbons. When the fuel contains little or no carbon, a single UV detector or heat detector is preferred. Flame detectors should be located no greater than 35 ft 10 m from possible fire sources. Flame detectors should be positioned to see the base of the fire not just the flames above it.
Enough flame detectors must be deployed to avoid blind spots and to account for loss in sensitivity away from the detector's central axis. To avoid false alarms from sources outside the risk area, flame detectors should not have a view of the horizon. Fire detectors shall cover all applicable facilities envisaged in the project. The following types of fire detectors shall be provided.
Heat sensing devices are viable alternatives in either case provided the potential flame location is well known and the sensing device can be located nearby. At 35 ft 10 m , the detector should respond in ten seconds to a 1 ft2 0. There are two kinds of fire control; passive and active fire protection system. Passive fire protection shall be applied to critical structures, boundaries, vessel and equipment. Fire protection of vessels and equipment.
Fire protection of shutdown valves. All shutdown valves shall be designed as fire-safe and shall be of a fail-closed design with spring return actuator. While blowdown valves shall be fire-safe and fail-open type. Fire protection of supports for vessel. Any supporting structure shall be fire proofed.
Fire protection of structural steel 5. Fire protection of proofing materials. It shall be either epoxy intumescent, subliming type or fibre containing panels and type approved for duration and ratings identified. The materials shall be suitable for use in an offshore environment, have an operational life of design life of platform, does not degrade by absorbing water. Below are the active fire protection systems 1.
Water deluge systems to cool areas and equipment that may be affected by radiated heat from a fire and prevent escalation and also to protect personnel from radiation at the bridge crossing. Air fin coolers Pressure vessel and heat Water monitors to support fixed fire protection systems to cool process areas and equipment that may be affected by radiated heat from a fire, provide local cooling at jet fire impingement areas on vessels, and prevent escalation.
Foam is used where there is a risk of a pool fire. Fire water pumps. The firewater pump shall be capable of supplying the maximum credible demand. Fire water distribution ringmain. It shall be located in the optimum location to protect from the effects of hydrocarbon fires and explosions.
Below should be considered forringmain. The plant design must therefore aim to minimize the damage. This is achieved by providing means to stop the release of flammable or hazardous materials as quickly as possible, by enabling the plant to withstand fire exposure without further failure while a fire is being extinguished, and by providing effective firefighting facilities.
The essential components of a plant design which are used to minimize the damage resulting from fires and explosions are listed below.
Fireproofing - Fireproofing of structural steelwork, vessels, and vessel supports provides protection against failure from fire exposure and additional release of fuel. Fireproofing is also employed to ensure the continued functioning of certain emergency systems under fire exposure This design guideline is believed to be as accurate as possible, but are very general and not for specific design cases. Fire Fighting Facilities - Adequate fixed and mobile firefighting facilities must be provided and be capable of meeting extinguishing and equipment cooling requirements for fires in all processing and offsite areas.
Emergency Facilities - Emergency facilities are required to reduce the release of flammable material feeding a fire as rapidly as possible. These facilities comprise remote shutdowns for certain items of equipment, emergency isolation and means of de- pressuring and removal of flammable inventory and water flooding capability.
Typical actions from fire gas detection and protection FDP systems are: 1. Alert personnel 2. Release firefighting systems 3. Emergency ventilation control 4. Stop flow of minor hydrocarbon sources such as diesel distribution to consumers. Isolate local electrical equipment may be done by ESD 6. Isolate electrical equipment 8. Close watertight doors and fire doors This design guideline is believed to be as accurate as possible, but are very general and not for specific design cases.
Figure 5. Failure in Safety Management This design guideline is believed to be as accurate as possible, but are very general and not for specific design cases. Inherent safety The inherent safety is the pursuit of designing hazards out of a process, as opposed to using engineering or procedural controls to mitigate risk. Therefore inherent safety strives to avoid and remove hazardous material and the number of hazardous operations in the plant rather than to control them by added-on systems.
The inherent safety is best considered in the initial stages of design, when the choice of process route and concept is made. An inherent safe plant relies on chemical and physical parameter to prevent accidents rather than on control systems, interlocks, redundancy, and special operating procedures to prevent accidents. Inherently safer plants are also more tolerable of errors and are often the most cost effective system that usually applied in plant. The process that does not need a complex safety interlocks and also elaborate procedures is simpler, easier to operate, and more reliable.
Reducing the dimension or equipment sizing and operating at less severe temperature and pressure condition will lead to decreasing its capital and operating costs. As in general, on the most literature explained that the safety of process is relies on multiple layers of protection. First layer is the process design features, and the next layer contains of many key factors in example : Control systems, interlock, shutdown systems, protective system, alarms, and emergency response plans.
Thus, inherent safety is a part of all layers of protection. However, the best approach to prevent accidents is to add process design features to prevent hazardous situations.
An inherently safer plant is often more tolerant for human errors and abnormal condition during running the process.
The most effective way of designing inherently safer plants is by intensification. Intensification step could be described as choosing and using smaller amounts of hazardous material. Thus, it will limit the damage in the incidents that occur. Intensification is also the preferred route to inherently safer design, as the reduction in inventory results in a smaller and cheaper plant.
Substitution step generally implied if intensification step is not possible to apply. Substitution means as replacing a hazardous material by a less one. In example using cyclohexane rather than benzene as a solvent. Blended component of mixture will cause a silent potential hazards that mostly people did not realize. Nonetheless, substituting a less substance for mixture component will lead to a safer composition of mixture.
A third method is called Attenuation. Attenuation means using hazardous materials in the least hazardous form. In example is storing a liquefied toxic or flammable materials at a low operating condition low temperature and low pressure. The function of this action to decrease the leak rate through a hole and avoid the evaporation process of materials. Limitation of effects constraint the available energy or the equipment design effect rather than by adding on protective equipment.
In example is handling corrosive liquids by plastic container or plastic-coated rather than other material construction which heated by an electric immersion heaters. Once the liquid level falls, exposing part of the heater, the container wall could get so hot and lead to a fire.
The inherently safer solution is to use a source of heat that less hot to ignite the plastic like low- pressure steam or low-energy electric heaters. Simplification is to made a system not only modest by its look but also from its function. Put the equipment orderly at the place where it should be is one of the example, such in piperack position and layout.
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