Sources of hazard

Other sources of hazard arise from the handling of such chemicals as concentrated acids, alkalis, metallic sodium and bromine, and in working with such extremely poisonous substances as sodium and potassium cyanides. The special precautions to be observed will be indicated, where necessary, in the experiments in which the substances are employed, and will also be supplied by the demonstrator. The exercise of obvious precautions and cautious handling will in most cases reduce the danger to almost negligible proportions. Thus, if concentrated sulphuric acid should be accidentally spilled, it should be immediately washed with a liberal quantity of water or of a solution of a mild alkali. 

In the past, hazardous wastes were often grouped into the following categories (1) radioactive substances, (2) chemicals, (3) biological wastes, (4) flammable wastes, and (5) explosives. The chemical cate-goiy included wastes that were corrosive, reactive, and toxic. The principal sources of hazardous biological wastes are hospitals and biological-research facilities. 

EPA is required to promulgate standards for all listed categories and subcategories of sources of hazardous air pollutants. 

List five categories (such as hazardous waste incineration) that may be considered as major" or "area sources of hazardous air pollutants,... 

It is generally agreed that a shelter with a roof having ridge ventilation and with curtain walls not extending lower than 8 feet above the operating platform would be freely ventilated. Because a gas compressor would not be a source of hazard, except under abnormal conditions such as an equipment failure, this type of compressor shelter is usually classified as a Division 2 area. 

Appendix B of the standard outlines a nonmandatory compliance section regarding hazard assessment and PPE selection. This Appendix outlines general guidelines for identifying, organizing, and analyzing sources of hazards and selection criteria for the appropriate PPE. 

Before entry is allowed into a vessel or other confined space, the vessel should be isolated from sources of hazardous material by slip-plating or physically disconnecting all pipelines and by isolating all supplies of electricity, preferably by disconnecting the cables. On the whole, these precautions seem to be followed. Accidents as the result of a failure to isolate are less common than those resulting from a failure to remove hazardous materials or from their deliberate reintroduction as described in Sections 11.1 and 11.2. However, the following are typical of the accidents that have occurred. 

The potential sources of hazards should be listed for risk assessment. SARA requires certain industries to provide information to the planning committee. Information about snuill as well as large industries is necessary to perinit the committee to evaluate tlie significant risks. Tlie information required by SARA (some of which was provided in Cliapter 2) includes ... 

IndusUy sites are not die only sources of hazards thus die proximity of haziirds to people and other sensitive enviroimiental receptors should be e.xa mined... 

Based on the material balance obtained in Table 1.1 for each unit operation, locate sources of hazardous waste... 

Linder, G. and M.E. Richmond. 1990. Feed aversion in small mammals as a potential source of hazard reduction for environmental chemicals agrichemical case studies. Environ. Toxicol. Chem. 9 95-105. 

To make an inventory of sources of hazardous chemical waste ... 

Nuclear energy, another source of hazards at DOE facilities, is not addressed in this document. 

Boatbuilders who use composites have, at most, just one more year before they have to reduce emissions to meet National Emission Standards for Hazardous Air Pollutants (NESH AP), also known as Maximum Achievable Control Technology (MACT) standards. By 23rd Aug. 2004, most boat manufacturing facilities subject to NESHAP must comply with 40 Code of Federal Regulations (CFR) Part 63, Subpart VVW. The deadline applies to existing boat manufacturing facilities that are major sources of hazardous air pollutants (HAPs). Existing sources are those that commenced construction on or before July 14, 2000. ( New sources , those that commenced construction after this date, must comply with emission limits at startup.) Major sources are facilities that have the potential to... 

Can be a source of hazard. Some may react violently to suggestions that they are not omniscient. Suggested reactions should never be undertaken without investigating safety factors, not even if the editor is the superior in question. 

Dust in the workplace is often considered to be merely a nuisance that has to be cleaned up once in a while. In some cases that s true. In others, however, as we have seen with lead, dust can be a significant source of hazard. The problems associated with dust will be considered in Chapter 9. 

Oil and Petrochemical Industries as Sources of Hazardous Organic Wastes... 

Mercury diffusion pumps are normally constructed from quartz or heat-resistant glass and are therefore a possible source of hazard should they Sreak, especially whilst they are hot. However, during over 40 years of working with such pumps, the author has neither experienced nor heard of such an accident. The major real disadvantage of mercury pumps is the relatively high vapour pressure of mercury at room temperature (ca. 10 Torr), which makes its necesssary to ensure that the cold traps prevent efficiently the mercury vapour from diffusing forward into the line. 

The major source of hazardous metals from chromating and other chemical conversion processes, as well as from electro- and electroless plating, is generally the process baths themselves. Spent cleaners and etchants also can contain large quantities of metal removed from workpieces. 

Compressed Air. Explosions have occurred in air compressors as a result of rapid oxidation of oil deposits in the piping between stages of multiple-stage compressors. Use of proper lubricants prevents deposition of oxidizable materials in high pressure piping (see LUBRICATION AND LUBRICANTS). High maintenance standards are required to detect and avoid the hazards associated with broken valves and other sources of hazardous recompression. 

Certain materials are a special source of hazard and their handling should be reviewed periodically... 

The toxic air pollution regulations in the 1990 amendments contain requirements expressly for hazardous waste emissions. The CAA established the National Emission Standards for Hazardous Air Pollutants (NESHAPs), which applies to those substances that are harmful to public health. A list of 188 substances has been developed that the USEPA must regulate under the CAA. Similar to nonhazardous pollutants, a source is designated as major if it discharges over 10 tons per year of any one of the 188 listed substances, or over 25 tons per year of any combination of substances. All other stationary sources of hazardous air pollutants are considered area sources. 

Modestly endothermic AHj (s) 50 kJ/mole, 0.8 kJ/g. Not a known source of hazard. See other ENDOTHERMIC COMPOUNDS... 

Seriously endothermic Aflf (1) 225 kJ/mole, 2.8 kJ/mole, but not a known source of hazard. 

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