Hazards, chemical

Materials used in UV/EB curing may present mainly hazards in skin and eye contact and, to a lesser degree, due to accidental ingestion. In some operations, where spray equipment is used, there is some possibility of inhalation of volatilized materials. 

Acrylate types of monomers and oligomers are known to be skin and eye irritants. Even if they do not cause irritation immediately, they may sensitize a person over a longer exposure and cause allergy. On the other hand, they represent much less of a hazard than common solvents (see Table 10.1). 

Recently, there has been an issue with the detection of 4-methylbenzophe-none (MBP) in breakfast cereal in Europe, leading to publicity concerning the presence of this photoinitiator in the food. Based on the close similarity between MBP and benzophenone, a photoinitiator for inks and coatings that are cured with UV light, the European Food Safety Authority (EFSA) has concluded that short-term consumption of breakfast cereals containing ppm traces of MBP should not pose a risk to most people, but recommended that this substance undergo more detailed evaluation if it will continue to be used in food packaging.  

Comparison of the Toxicity and Other Properties of UV/EB Curable Systems with Common Solvents 

Chemical Flash Point, °F voc Flazardous Waste Skin Irritant Toxicity Reproductive Effects 

The younger child and toddler are susceptible to exposure from chemicals in solid food (e.g. pesticides) and air (e.g. particulate matter) and through dermal exposure (e.g. heavy metals in soil). As children are introduced to day care and schools, potential new sources of exposure to certain chemicals (e.g. cleaning agents) may occur. Older children continue to be exposed to chemicals present in 

Some substances pose a direct hazard in the workplace, an example of which is vinyl chloride, the inhalation of which may cause a characteristic form of liver cancer. Other substances are those liberated in the processing of otherwise benign materials, for example, toxic by-products liberated during the machining or heating of otherwise harmless polymers. An important tool to warn against the harmful effects of substances consists of the material safety data sheet (MSDS), which, under OSH A regulations, must be provided to vendors of materials. 

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Chemical Hazards. Chemical manufacturers and employees contend with various ha2ards inherent ia productioa of evea commonplace materials. For example, some catalysts used ia the manufacture of polyethylene (see Olefin polymers) ignite when exposed to air or explode if allowed to become too warm the basic ingredient ia fluorocarboa polymers, eg, Tefloa (see Fluorine compounds, organic), can become violently self-reactive if overheated or contaminated with caustic substances (45,46) one of the raw materials for the manufacture of acryflc fibers (see Fibers, acrylic) is the highly toxic hydrogen cyanide (see Cyanides). 

The reaction between urea and Aiming sulfuric acid is rapid and exothermic. It may proceed with violent boiling unless the reaction temperature is controlled. The reactants are strongly acidic. Therefore, operators should wear suitable protective gear to guard against chemical hazard. Special stainless steel, mbber lining, fiber-reinforced plastics, and polyvinyl chloride and carbon equipment are used. 

G. Cla57ton and F. Cla57ton, eds., Patty s Industrial Hygiene andToxicology, 3rd ed., Vol. 2A, John Wdey Sons, Inc., New York, 1981, pp. 2089—2091. "Aryl Sulfonic Acids and Salts," Information Profiles on Potential Occupational Hayards, Vol. II, Chemical Classes, Center for Chemical Hazard Assessment, Syracuse Research Corp., U.S. Dept, of Commerce, Washington, D.C., 1979. 

G. E. Rubino, G. Scansetri, and G. Piolatto, Proceedings of the MIX International Congress of Occupational Health, Vol. 1, Chemical Hazards. Institute of Medical Reseaich of Occupational Health, Zagreb, Yugoslovia, 1980, p. 021. 

Reactive System Screening Tool (RSST) The RSST is a calorimeter that quickly and safely determines reactive chemical hazards. It approaches the ease of use of the DSC with the accuracy of the VSP. The apparatus measures sample temperature and pressure within a sample containment vessel. Tne RSST determines the potential for runaway reactions and measures the rate of temperature and pressure rise (for gassy reactions) to allow determinations of the energy and gas release rates. This information can be combined with simplified methods to assess reac tor safety system relief vent reqiiire-ments. It is especially useful when there is a need to screen a large number of different chemicals and processes. 

Two standard estimation methods for heat of reaction and CART are Chetah 7.2 and NASA CET 89. Chetah Version 7.2 is a computer program capable of predicting both thermochemical properties and certain reactive chemical hazards of pure chemicals, mixtures or reactions. Available from ASTM, Chetah 7.2 uses Benson s method of group additivity to estimate ideal gas heat of formation and heat of decomposition. NASA CET 89 is a computer program that calculates the adiabatic decomposition temperature (maximum attainable temperature in a chemical system) and the equilibrium decomposition products formed at that temperature. It is capable of calculating CART values for any combination of materials, including reactants, products, solvents, etc. Melhem and Shanley (1997) describe the use of CART values in thermal hazard analysis. 

The toller needs to be familiar with all raw materials, intermediate materials, products and wastes, used, produced or generated, respectively, while operating the process. Tollers in the U.S. should comply with the Federal OSHA Hazard Communication Standard, codified as 29 CFR. 1910.1200 and any similar state right-to-know laws that are currently in force or may be enacted during the term of the contract. This is often stated in the contract. The contract may require the toller to inform its employees of the chemical hazards associated with products or chemicals and may also be responsible for training its employees in the proper handling methods. The toller has an obligation when in doubt about a product or chemical, to seek further information from the product s manufacturer. 

Process Overview The process overview includes topics related to the equipment configuration, chemical and physical changes achieved in the specific toll, and special safe work practices related to the operations, maintenance and materials. Emphasis should be given to any new equipment and chemical hazards the startup team will encounter. 

L. Bretherick, P.G. Urbcn and M.J. Pitt, Bretherick s Handbook of Reactive Chemical Hazards An Indexed Guide to Published Data, 6th Edn, Butterworth-Heinemann, Oxford, 1999. ISBN 075063605X. 

G.J. Hathaway, Chemical Hazards of the Woriqplace, 4th Edn, J. Wiley Sons,1996. ISBN 0471287024. 

Since data have been collated from a variety of sources, and tend to be presented in mixed units, and because rapid conversion of units is an advantage in many on-site situations, conversion tables are included in Chapter 18. Finally, since safety with chemicals cannot be addressed exhaustively in a handbook, selected sources of reliable current information on chemical hazards and their control are listed in Chapter 19. 

Defined substances covered by a comprehensive system to inform consumers of potential dangers and to reduce the hazard when carried by road. The Chemical (Hazard Information and Packaging for Supply Regulations 1994). 

Reactive chemical hazards may arise from the inherent properties of the chemicals handled, used or disposed of and/or from their admixture or processing. 

Figure 7.1 Possible reactive chemical hazards (consequences are not mutually exclusive)...

The Chemicals (Hazard Information and Packaging for Supply) Regulations 1994 as amended... 

Bretherick, L. (1990J Handbook of Reactive Chemical Hazards, 4th edn, Butterworth-Hememann, Oxford. 

Cover the control of substances classified as very toxic, toxic, harmful, coiTosive, sensitizing or imtant under the Chemicals (Hazard Information and Packaging for Supply) Regulations 1994 (as amended) and to substances which have MELs or OESs. Also other substances that have chronic or delayed effects and biological agents. Special provisions are included for carcinogens. 

Quick Guide The Electronic NIOSH Pocket Guide to Chemical Hazards, Version 4.0. 

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