Exposure chemical

WorkingS olution Regeneration and Purification. Economic operation of an anthraquinone autoxidation process mandates fmgal use of the expensive anthraquinones. During each reduction and oxidation cycle some finite amount of anthraquinone and solvent is affected by the physical and chemical exposure. At some point, control of tetrahydroanthraquinones, tetrahydroanthraquinone epoxides, hydroxyanthrones, and acids is required to maintain the active anthraquinone concentration, catalytic activity, and favorable density and viscosity. This control can be by removal or regeneration. 

Products. Vibration isolators typically are selected to have a static deflection, under load, that yields a natural frequency no more than one-third the lowest driving frequency that must be isolated (see Eig. 7). The supporting stmcture must have sufficient stiffness so it does not deflect under the load of the supported equipment by more than one-tenth the deflection of the isolator itself (6). In addition to static deflection requirements, vibration isolators are selected for a particular appHcation according to their abiHty to carry an imposed load, and to withstand the environment in which they are used (extreme temperatures, chemical exposure, etc). 

Appropriate protective clothing and equipment should be worn to minimize exposure to methacrylate liquids and vapors. Chemically resistant clothes and gloves and splash-proof safety goggles ate recommended. The working area should be adequately ventilated to limit vapors. Should chemical exposure occur, contaminated clothing should be removed and the affected area washed with copious amounts of water. Medical attention should be sought if symptoms appear. Eurther information about methyl methacrylate and other methacrylates is available (141). 

The long latent periods involved in development of cancers make correlation of chemical exposures and disease extremely difficult. This can be countered pardy with tests on naturally short-Hved animals. Tests on bacteria, eg, the Ames test, may permit rapid detection of cancer potential, although there is no direct relationship between the results of bacterial tests and the effects of the tested chemicals on humans (56). 

One early program carried out at AUied-Signal, Inc. proposed the use of conductive polymers in remotely readable indicators (210). Conductivity changes induced in the conductive polymer could be read externally and the history of the sample known. Systems designed to detect time—temperature, temperature limit, radiation dosage, mechanical abuse, and chemical exposure were developed. 

Reactive Chemicals Exposure. The ha2ards associated with exposure to reactive chemicals vary with the chemicals produced. The multitude of chemicals produced electrochemically precludes a detailed discussion of these ha2ards. Material Safety Data Sheets (MSDS) are available from suppHers. Anyone contemplating the production of a chemical must become thoroughly familiar with all safety, health, and environmental aspects of such production. 

Chemical Exposure Index (CEI) The CEI provides a method of rating the relative potential of acute health hazard to people from possible chemical release incidents. 

Chemical Exposure Index (CEI) Chemical Exposure Index, 1994). The CEI provides a method of rating the relative potential of acute health hazard to people from possible chemical release incidents. It may be used for conducting the initial process hazard analysis and it establishes the degree of mrther analysis needed. The CEI also may be used as part of the site review process. 

Relative Ranking (DOW Fire and Explosion and Chemical Exposure Index) to evaluate siting/layout considerations... 

Cement and Concrete Concrete is an aggregate of inert reinforcing particles in an amorphous matrix of hardened cement paste. Concrete made of portland cement has limited resistance to acids and bases and will fail mechanically following absorption of crystalforming solutions such as brines and various organics. Concretes made of corrosion-resistant cements (such as calcium aluminate) can be selected for specific chemical exposures. 

Table 13.8 Standard first aid treatments for chemical exposure...

Ashford, N., and Miller, C. (1998J Chemical Exposures, High Levels and High Stakes, 2nd edn. Van Nostrand Remhold, New York. 

Terms and Phrases used in the Chemical Exposure Treatment Cards (1992)... 

Cullis, C.R, and Firth, J.G. (ed.) (1988) Detection and Measurement of Hazardous Gases, Hememann, London. Daugherty, J., (1997) Assessment of Chemical Exposures Calculation Methods for Environmental Professionals, Lewis Publishing, London. 

HS(Gjl67 Biological monitoring m the workplace - a guide to its practical application to chemical exposure... 

The threshold for toxic injury is not the same for everyone because sensitivity varies greatly among individuals. Most chemicals in consumer products remain untested for health effects, such as cancer, reproductive problems, and the impacts of long-term, low level exposure. How these substances affect women, children, and people with existing conditions is also little studied. Once a person s defenses have been broken down and he or she has become hypersensitive, a wide variety of common chemical exposures can trigger a reaction. Just what products and other chemicals which cause problems varies greatly among affected individuals. 

Refer to the handbook s Glossary. The definitions provided are universally recognized. Many of these terms are not just pertinent to inhalation hazards. It would be remiss not to mention other risks beyond inhalation from chemical exposure in a work environment and to the general public. 

Passive diffusion sorbent badges are useful for screening and monitoring certain chemical exposures, especially vapors and gases. 

MESOCHEM Chemical Atmospheric and Hazard Assessment System Impell Corporation Becky Cropper 300 Tristate Internat l Suite 400 Lincolnshire, IL 60069 (312) 940-2090 Software for atmospheric dispersion and chemical exposure assessment. A plume dispersion model. 

Tools are available to assist in comparing the risk associated with two or more different processes. For example, the first sheet of the Dow Fire and Explosion Index (FEI) (Dow, 1994b) ranks the safety characteristics of the process from a fire/explosion standpoint, without taking credit for protective and mitigation features. The Dow Chemical Exposure Index (CEI) (Dow, 1994a) and Id s Mond Index (ICI, 1985 Tyler, 1985) are other ranking tools. 

Dow Chemical Company (1994a). Dow s Chemical Exposure Index Guide. 1st Edition. New York American Institute of Chemical Engineers. 

In addition, responses to releases of hazardous substances where there is no potential health or safety hazard (i.e., fire, explosion, or chemical exposure) are not considered to be emergency responses. Keep in mind that qualified personnel who are trained to clean up incidental... 

Is positive pressure self-contained breathing apparatus (SCBA) or positive pressure air-line respirator and escape air supply used when chemical exposure will create a substantial possibility of immediate death, immediate serious illness or injury, or impair the ability to escape ... 

The primary limitation of a HAZOP study is the length of time required to perform it. Because the study is designed to provide a complete analysis, study sessions can be intensive and lii ing. HAZOP studies typically do not look at occupational hazards (e.g., electrical equipment, rotating equipment, hot surfaces) or chronic hazards (e.g., chronic chemical exposure, noise, heat stress). For experience with HAZOP see Swann (1995). 

---