Hazards intrinsic

It implements the Precautionary Principle. Arguments against the Precautionary Principle commonly centre on what degree of evidence of harm is necessary before action is taken to restrict the use of a substance. When applying the Substitution Principle, it is not necessary to wait for cancers, reproductive disorders or genetic defects and elusive evidence of cause and effect. If alternatives with less hazardous intrinsic properties are available, use of the hazardous substance is not permitted. The potential for harm is then reduced or avoided altogether. 

Automatic phasing-out over time of CMRs, PTBs, vPvBs and chemicals with other hazardous intrinsic properties. 

Job safety analysis (JSA) is concerned with uncovering and rectifying potential hazards intrinsic to or inherent in the workplace. Usually, workers, supervisors, safety professionals, and management participate in JSA. JSA is composed of fhe following five steps [1,12] ... 

ISA RP 12.6. 1987. Installation of Intrinsically Safe Systems for Hazardous (Classified) Locations. (ANSI approved.) Instrument Society of America, Research Triangle Park, N.C. 

Intrinsically Safe Equipment and wiring which is incapable of releasing sufficient electrical or thermal energy under normal or abnormal conditions to cause ignition of a specific hazardous atmospheric mixture or hazardous layer. 

Textile motors Crane motors Determining the size of motor Sugar centrifuge motors Motors for deep-well pumps Motors for agricultural application Surface-cooled motors Torque motors or actuator motors Vibration and noise level Service factors Motors for hazardous locations Specification of motors for Zone 0 locations Specification of motors for Zone I locations Motors for Zone 2 locations Motors for mines, collieries and quarries Intrinsically safe circuits, type Ex. f Testing and certifying authorities Additional requirements for ciritical installations Motors for thermal power station auxiliaries Selection of a special-purpose motor... 

If sufficient experience does not exist, you should consider whether the consequence potential (Step 4) or the expected frequency of accidents (Step 5) is great. Consideration of consequence potential should include personnel exposure, public demographics, equipment density, and so forth in relation to the intrinsic hazard posed by the material of concern. In Step 5 you may perceive that the expected frequency of accidents alone is important enough to justify a QRA. However, even though your company may not have much relevant experience with the activity of interest, if the consequence potential of these accidents is not great, you may conclude that the expected frequency of the potential accidents is low enough for you to make your decisions comfortably using qualitative information alone. 

Must be air purged, explosion proof, or intrinsically safe to be used in hazardous areas. 

What do we mean when we speak of an inherently safer chemical process Inherent has been defined as existing in something as a permanent and inseparable element, quality, or attribute (American College Dictionary, 1967). A chemical manufacturing process is inherently safer if it reduces or eliminates the hazards associated with materials and operations used in the process, and this reduction or elimination is permanent and inseparable. To appreciate this definition fully, it is essential to understand the precise meaning of the word hazard. A hazard is defined as a physical or chemical characteristic that has the potential for causing harm to people, the environment, or property (adapted from CCPS, 1992). The key to this definition is that the hazard is intrinsic to the material, or to its conditions of storage or use. Some specific examples of hazards include ... 

If a chemical process requires the concentrated form of the material, it may be feasible to store a more dilute form, and to concentrate the material by distillation or some other technique in the plant prior to introduction to the process. The inventory of material with greater intrinsic hazard (i.e., undiluted) is reduced to the minimum amount required to operate the process, but the distillation adds a new hazardous process. 

The design of intrinsically safe equipment is governed by the rules of NFPA Publication No. 493, Standard for Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Division 1, Hazardous Locations. It is cautioned, however, that the design of intrinsical-... 

The mere fact that voltage, current, or even both, are at low levels does not guarantee a circuit to be intrinsically safe, even though intrinsically safe circuits do utilize relatively low voltage and current levels. Intrinsically safe systems employ electrical barriers to assure that the system remains intrinsically safe. The barriers limit the voltage and current combinations so as not to present an ignition hazard should a malfunction develop. Typically, devices upstream of barriers are not intrinsically safe and are installed in control rooms or other unclassified locations. All devices and wiring on the downstream side of the barriers are intrinsically safe and can be installed in classified areas. 

An additional benefit of intrinsically safe systems is the reduction of electrical shock hazards. It is cautioned, however, that intrinsically safe systems are not necessarily tested specifically for personnel shock hazards. 

C22.2, No. 157 Intrinsically Safe and Nonincendive Equipment for Use in Hazardous Locations... 

RP12.1 Recommended Practice for Electrical Instruments in Hazardous (Classified) Atmospheres Intrinsic Safety... 

RP12.6 Installation of Intrinsically Safe Instrument Systems for Hazardous (Classified) Locations... 

Standard for Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, IE and III, Division 1 Hazardous Locations... 

Optical fiber cables and fiber optic devices approved as an intrinsically safe system suitable for the hazardous (classified) location involved shall be installed in accordance with Sections 504-20 and 770-52. 

Intrinsically Safe Systems. Intrinsically safe apparatus and wiring shall be permitted in any hazardous (classified) location for which it is approved, and the same provisions of Articles 501 through 503, 505, and 510 through 516 shall not be considered applicable to such installations, except as required by Article 504. 

Under the RCRA exemption, wastes intrinsically associated with the exploration and development of oil and gas do not have to follow Subtitle C regulations for disposal. Under Subtitle C, hazardous wastes must follow strict guidelines for storage, treatment, and transportation and disposal. The cost of handling materials under the Subtitle C scenario is overwhelming. Under the exemption, the operator is allowed to dispose of wellsite waste in a prudent manner and is not obliged to use licensed hazardous waste transporters and licensed Treatment, Storage, and Disposal Facilities (TSDF). 

Where a.c. supplies exist, transformer-rectifiers are the most economical source of d.c. for cathodic protection systems. In the case of pipelines, standard transformer-rectifiers, either oil or air cooled, can be employed. They range in size from 5A, 5V for small systems to 100 A, 48 V for major pipeline schemes. A typical output for a well-coated cross-country pipeline in the UK would be 5 A, 48 V. In the case of sea-water jetties where the voltage required is usually low because of the lower sea-water resistivity, a typical rectifier size for a major installation would be 500 A, 18 V. For offshore pipelines and loading platforms where a fire hazard exists, it is usual to employ certified flameproof or intrinsically safe rectifiers to overcome any possibility of fire hazard should faults develop in the unit. 

Provisions for primary and emergency communications (internal and external telephone links and radios) require careful assessment. If there is a flammable hazard on site, radios may need to be intrinsically safe or flameproof. 

Where possible plants of intrinsically safe design are preferred, i.e. those which have been designed to be self-correcting rather than those where equipment has been added on to control hazards. Some characteristics of intrinsically safe plants are ... 

Benson and Ponton propose, based on this analysis, the concept of distributed manufacturing [139, 145], which will be referred to in detail in Volume 2 of this book series. Basically, they refer to small, transportable plants which are fed with reactants over the fence , hence using only non-hazardous, generally available materials by normal piping or standard transport. If an aggressive chemical is needed, it has to be made from environmentally friendly base materials as an intermediate on-site. Needless to say, effluents have to be completely harmless, plant operation has to be intrinsically safe, and the plant should be clean and quiet. 

This relationship clearly shows that risk is a function of both the intrinsic hazard of a chemical and the exposure to that chemical which includes the frequency, duration and... 

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