Hazards continued equipment

The fine chemicals business is characterized by a small volume of products manufactured. Therefore, batch production predominates and small-scale reactors are used. The need to implement fine chemistry processes into existing multiproduct plants often forces the choice of batch reactors. However, safety considerations may lead to the choice of continuous processing in spite of the small scale of operation. The inventory of hazardous materials must be kept low and this is achieved only in smaller continuous reactors. Thermal mnaways are less probable in continuous equipment as proven by statistics of accidents in the chemical industries. For short reaction times, continuous or semicontinuous operation is preferred. 

The throughput for a given equipment size is far superior in continuous reactors, but problems with transients and maintaining quaHly in continuous equipment mandate serious analysis of reactors to prevent expensive malfunctions. Large equipment also creates hazards that backyard processes do not have to contend with. 

An incident creates a dynamic environment, the decisions made in the initial analysis and the corresponding responses are critical to a desirable outcome. The continued thoughtful consideration of the interdependencies between the hazards, location, equipment, personnel, and cascading effects will make for sound decision making and appropriate resource allocation. 

At many active workplaces, daily site inspections are performed by the supervisor in order to detect hazardous conditions, equipment, materials, or unsafe work practices. At other times, periodic site inspections are conducted by the site safety and health officer. The frequency of inspections is established in the workplace safety and health program. The supervisor, in conjunction with the safety and health officer, determines the required frequency of these inspections, based on the level and complexity of the anticipated activities and on the hazards associated with these activities. In a review of worksite conditions/activities, site hazards, and protecting site workers, the inspections should include an evaluation of the effectiveness of the company s safety and health program. The safety and health officer should revise the company s safety and health program as necessary to ensure the program s continued effectiveness. 

Hazard identification requires the identification of hazards, unsafe conditions, and risky behaviors. Hazard anticipation relies on human intuition, training, common sense, observation, and continuous awareness. To identify hazards, rely on the use of inspections, surveys, analysis, and human recognition reporting. Hazard identification efforts should focus on unsafe conditions, hazards, broken equipment, and human deviations from accepted practices. Require supervisors or unit safety coordinators to conduct periodic area inspections. These individuals should understand hazardous areas and the workers better than anyone. However, supervisors can fall prey to inspection bias, which results in poor survey results. Many supervisors conduct limited ongoing inspections... 

An important newer use of fluorine is in the preparation of a polymer surface for adhesives (qv) or coatings (qv). In this apphcation the surfaces of a variety of polymers, eg, EPDM mbber, polyethylene—vinyl acetate foams, and mbber tine scrap, that are difficult or impossible to prepare by other methods are easily and quickly treated. Fluorine surface preparation, unlike wet-chemical surface treatment, does not generate large amounts of hazardous wastes and has been demonstrated to be much more effective than plasma or corona surface treatments. Figure 5 details the commercially available equipment for surface treating plastic components. Equipment to continuously treat fabrics, films, sheet foams, and other web materials is also available. 

In selec ting the machines of choice, the use of specific speed and diameter best describe the flow. Figure 10-67 shows the characteristics of the three types of compressors. Other considerations in chemical plant service such as problems with gases which may be corrosive or have abrasive solids in suspension must be dealt with. Gases at elevated temperatures may create a potential explosion hazard, while air at the same temperatures may be handled qmte normally minute amounts of lubricating oil or water may contaminate the process gas and so may not be permissible, and for continuous-process use, a high degree of equipment rehability is required, since frequent shutdowns for inspec tion or maintenance cannot be tolerated. 

Inert gas-filled motors can also be used in refineries and chemical plants, but their applications are limited. They have tightly fitted covers and oil seals around the shaft to minimize gas leakage, are continually pressurized with an inert gas or instrument air, and are equipped with an internal air-to-water heat exchanger. Inert gas-filled motors are suitable for any hazardous location but require auxiliaries such as cooling water, gas pressurizing system, and control accessories. 

Health Hazards Information - Recommended Personal Protective Equipment Face shield to avoid splash Symptoms Following Exposure Very high vapor concentrations irritate eyes and upper respiratory tract. Continued contact with skin may cause irritation General Treatment for Exposure EYES immediately flush with plenty of water for at least 15 min. get medical attention. SKIN flush with water wash with soap and water Toxicity by Inhalation (ThresholdLimit Value) QO ppm Short-Term Inhalation Limits Data not available Toxicity by Ingestion Grade 2, LDjq 0.5-5 g/kg Late Toxicity None Vapor (Gas) Irritant Characteristics Vapor is moderately irritating such that personnel will not usually tolerate moderate or high vapor concentrations Uq or Solid Irritant Characteristics Liquid may irritate skin Odor Threshold Data not available. 

After the hazard assessment has been conducted and the data has been collected, it should be organized in a logical outline that will estimate the potential for employee injury The organized data will help to decide the type of hazard(s) involved, the level of risk, and the seriousness of potential injury The appropriate levels of PPE are then selected based on the hazard determination and the availability of PPE. The user should be properly fitted for the specified PPE, and the employer should make sure that it is comfortable to wear. Hazard reassessments should be conducted as necessary based on the introduction of new or revised processes, equipment, and accident experience, to ensure the continued suitability of selection of the proper PPE. 

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