Hazards with

In the first step, a screening process will be applied to separate the major potential hazards these will be addressed in more detail. QRA techniques are used to evaluate the extent of the risk arising from hazards with the potential to cause major accidents, based on the prediction of the likelihood and magnitude of the event. This assessment will be based on engineering judgement and statistics of previous performance. Where necessary, risk reduction measures will be applied until the level of risk is acceptable. This of course is an emotive subject, since it implies placing a value on human life. 

Dust Filter. The cloth or bag dust filter is the oldest and often the most reHable of the many methods for removing dusts from an air stream. Among their advantages are high (often 99+%) collection efficiency, moderate pressure drop and power consumption, recovery of the dust in a dry and often reusable form, and no water to saturate the exhaust gases as when a wet scmbber is used. There are also numerous disadvantages maintenance for bag replacement can be expensive as well as a sometimes unpleasant task these filters are suitable only for low to moderate temperature use they cannot be used where Hquid condensation may occur they may be hazardous with combustible and explosive dusts and they are bulky, requiring considerable installation space. 

Safety. Shampoos generally do not represent a hazard with regard to skin and eye safety once used, shampoos are almost immediately rinsed and have Httie contact time on sensitive areas. To assure this safety, provisions to test the finished product for skin and eye irritation should be made. 

There are explosion hazards with phthahc anhydride, both as a dust or vapor in air and as a reactant. Table 11 presents explosion hazards resulting from phthahc anhydride dust or vapor (40,41). Preventative safeguards in handling sohd phthahc anhydride have been reported (15). Water, carbon dioxide, dry chemical, or foam may be used to extinguish the burning anhydride. Mixtures of phthahc anhydride with copper oxide, sodium nitrite, or nitric acid plus sulfuric acid above 80°C explode or react violently (39). 

Thorium is potentially hazardous. Einely divided thorium metal and hydrides can be explosive or inflammatory hazards with respect to oxygen and halogens. Einely divided Th02 and other inorganic salts also present an inhalation and irritation hazard. The use of standard precautions, skin covering, and a conventional dust respirator should be sufficient for handling thorium materials. 

Methyl bromide is nonflammable over a wide range of concentrations in air at atmospheric pressure and offers practically no fire hazard. With an intense source of ignition, flame propagation within a narrow range from 13.5 to 14.5% by volume has been reported. The material has no flash point. Thermal decomposition in a glass vessel begins somewhat above 400°C. 

Further dechlorination may occur with the formation of substituted diphenyhnethanes. If enough aluminum metal is present, the Friedel-Crafts reactions involved may generate considerable heat and smoke and substantial amounts of hydrogen chloride, which reacts with more aluminum metal, rapidly forming AlCl. The addition of an epoxide inhibits the initiation of this reaction by consuming HCl. Alkali, alkaline-earth, magnesium, and zinc metals also present a potential reactivity hazard with chlorinated solvents such as methylene chloride. 

The assessor should determine whether any serious effort is being undertaken by the toller to examine all tasks in detail to identify possible exposure risks, for example, is opening of a tank lid manhole a potential health hazard with certain chemicals ... 

Electric cyclones, which utilize an electrode in the center of the cyclone to establish an electric field within the cyclone body. This device is more efficient than the standard cyclone. It is probably more applicable to mists and droplets than to dry particulates, due to possible fire or explosion hazards with combustible dusts. 

Aldehyde-amines Aldol-naphthylamines Yes Not often used. Possibilities of carcinogenic hazard with some types. 

The hazards with glutaraldehyde are those of irritation to the skin, eyes, throat, and lungs. It can cause dermal and respiratory sensitization, resulting in rhinitis and conjunctivitis or asthma. In the UK the Maximum Exposure Limit is just 0.05 ppm (8 hr TWA limit) and 0.05 ppm (15 min STEL) with a Sen notation (p. 93). 

Provision of information and instmetion to personnel as to the hazards with the speeifie ehemieal, ineluding possible reaetions. 

The two different, but related, eonsiderations in waste disposal are hazard eontrol and loss prevention in the treatment and disposal operations, and the eontrol of environmental hazards. With gas and liquid streams the eontrol of on-site hazards arising from the ehemieal properties and proeessing operations generally follows the prineiples summarized in earlier ehapters. The measures neeessary with solid wastes may, however, differ, partieularly if they are heterogeneous in nature and disposed of on land. 

The ultimate goal of inherently safer design is elimination of all hazards with no need for controls. However, some control systems are always required. The working logic of a specific control system can make it inherently safer than other alternatives. 

Qualitative results of checklist analyses vary, but generally the analysis produces the answers yes, no, not applicable, or needs more information. The checklist is included in the PrHA report to summarize the noted deficiencies. Understanding these deficiencies leads to sa fety improvement alternatives for consideration, and to identified hazards with suggested actions. I igtires 3.3,1-4 and 3.3.1-5 present checklist analyses of the Dock 8 HF Supply and the Cooling tower chlorination respectively. 

Another hazard with centrifuges is that if they turn the wrong way, the snubber can damage the basket. It is therefore much more important than with pumps to make sure this does not occur. 

Another hazard with air coolers is that even though the motor is isolated, air currents have caused the fans to rotate while they were being maintained. Fans should therefore be prevented from moving before any maintenance work is carried out on or near them. 

Palmer, K. N. 1960. The Quenching of Flames hy Perforated Sheeting and Block Flame Arresters. Proc. Symposium on Chemical Process Hazards with Special Reference to Plant Design, pp. 51-57. Institution of Chemical Engineers, Rughy, England. 

In addition to varying in costs, the chemical composition of the water provided from the mains supply also varies between the water companies, as may that between independent supplies within each company s area. The current criterion on potable water quality requires it to be wholesome i.e. it should not create a health hazard, with relatively wide limits on particular constituents. The cost of removing these constituents (e.g. calcium, magnesium, chlorides, iron and silica) increases with concentration and variability. This imposes a cost burden on, for example, the semiconductor and electronic component industries and on the operation of high-pressure boilers. Therefore both the potential cost of metered water supply and the chemical composition of the supply waters may influence future decisions on the water company s area in which an industry may wish to locate. 

The main hazards with cryogens stem from ... 

Low-boiling-point materials can cause frostbite on contact with living tissue. While this is an obvious hazard with cryogenics, e.g. liquid nitrogen or oxygen, cylinders of other liquefied gases also become extremely cold and covered in frost as the contents are discharged. 

As with the case of mass, there are several approaches to metrics for this aspect. One can simply sum numbers and/or mass of chemicals possessing hazards in different areas for example, process safety, occupational exposure, or environmental hazard. Typically, most companies will use a banding approach for materials that allows a quick identification of the hazard category, and usually marries hazard with a suggested control approach for example, layers of protection, pressure relief valves, and so on. One is then able to rapidly identify issues and potential opportunities for elimination, substitution, or control. 

One last hazard with cryogens is that they may lead to local build-up of oxygen through liquefaction of air. When filling a magnet, it is possible to see liquid air condensing at the fill port. If this happens,... 

It decomposes explosively at the m.p., 98°C [1], and shows a high rate of pressure increase on exothermic decomposition [2], The heat of decomposition was determined as 1.34 kJ/g by DSC, and Taii24 was determined as 88°C by adiabatic Dewar tests, with an apparent energy of activation of 223 kJ/mol [3], When finely divided, it also shows significant dust explosion hazards, with a maximum explosion pressure of 7.75 bar, and a maximum rate of pressure rise above 680 bar/s [4], Further work on homogeneous decomposition under confinement has been reported [5],... 

The hexasolvated complex may be hazardous with respect to detonation. Other metal perchlorates and nitrates solvated with DMSO are explosive. 

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