Airborne chemical hazards

TWA Time Weighted Average. Usually, a personal, eight-hour exposure concentration to an airborne chemical hazard. 

Hazardous Air Pollutants (HAP) airborne chemicals that cause serious health and environmental effects. 

Atmospheric Hazards. Examples are Uie presence of toxic airborne chemical substances and parUculate matter, biological agents, noise, vibration, radiation, extremes of temperature and humidity, and lack of illumination. 

The evaluation of hazards posed to human health by toxic airborne chemicals is one of the common tasks employed in industrial hygiene. This process requires the collection of air samples to estimate air concentrations of specific substances inhaled by workers which can then be compared with standards and guides of acceptable exposure. Thus air sampling directly influences the formulation of important decisions. If air samples underestimate exposures, the consequence may be death or occupational disease. Conversely, overestimating exposures may result in the institution of unnecessary controls. Since either form of error is undesirable, it is fundamentally important that air sampling accurately define the extent of hazard. This requires that air samples be collected according to scientific, unbiased schemes for estimating exposures to toxic airborne chemicals. 

Recent developments in the field of sensing airborne chemicals using electrochemical sensors and sensor arrays are reviewed. Such systems detect, Identify, and quantify potential chemical hazards to protect the health and safety of workers and citizens. The application discussed In this review article Is single chemicals at part-per-million levels in air. The sensor system consists of an array of sensors used In four modes of operation, and the data are Interpreted by a computer algorithm. Pattern recognition techniques are being used to understand the information content of the arrays and to focus future experimental work. 

The major concern for the region is the open burning of domestic wastes and forest fires in the tropical forest belt of Southeast Asia that resulted in severe hazes and the release of hazardous airborne chemicals, particularly PAHs. It became such a regional crisis that a Regional Haze Action Plan was instituted in 2001 to address the issue of transboundary haze (ASEAN, 2006). 

Gunderson, E. C. Sampling Methods for Airborne Pesticides in Chemical Hazards in the Workplace, (ed.) Choudhary, G., ACS Symp. Series 149, Washington, D.C., ACS 1981... 

There must be a procedure or statement in the plan as to how transient employees, such as persons working on contract, are to be informed of the chemical hazards to which they may be exposed, and for provision of information of protective measures for these transient employees. It is not specifically spelled out in the standard but there is a need for the converse as well. Contractors are often called in to do renovations, perform an asbestos abatement project, or to conduct a pest control program, as examples, and use hazardous chemicals in the process or expose persoimel to airborne hazards. Provision should be made in the contracts for these groups for them to provide information to the occupants of the spaces where their work is being done. 

Atwork or at home, have you everbeen exposed to hazardous solvents, hazardous airborne chemicals (e.g., gases,fumes, or dust), or have you come into skin contact withhazardous chemicals Yes/No... 

Chemical hazards arise from excessive airborne concentrations of mists, vapors, gases, or solids that are in the form of dusts or fumes. In addition to... 

Is ai one exposed to the chemical hazard If so, who How often How much The last question may require expert assistance with air samphng, but in mai r cases this will not be necessary. For instance, maity substances may not result in airborne exposure from dust, vapour, gas, lume or mist. Instead, at r potential contact m be with the skin. The substance may or may not be absorbed via the skin. Does the substance act on contact or is it absorbed to go on and affect other target organs Poor personal hygiene could result in ingestion (swallowing) if the chemical is on hands and the worker bites nails or eats or smokes with imwashed hands. 

Biological monitoring of worker exposure to chemical hazards through analysis of samples of blood, urine, expired air, etc. is required in those cases where measurement of airborne concentration alone is not a reliable indicator of exposure hazard. In some instances, the... 

Class I. Air is contaminated by hazardous fumes or vapors including gases and airborne chemicals. This is subdivided into two divisions. 

Ultimately, you should have two goals in mind as you read this first, to understand the concept of OELs and their variations as tools to protect workers (including those in laboratories) from adverse airborne chemical exposures and to understand that some OELs are voluntary and some are legal requirements and second, to understand how you can use this information to assess the relative risk of a hazard. 

Chemical hazards, especially airborne gases, vapors, dusts, or fumes that pose inhalation hazards as well as skin irritants and toxicants that may be absorbed through the skin... 

Chemical hazards arise from excessive airborne concentrations of mists, vapors, gases, or solids that are in the form of dusts or fumes. In addition to the hazard of inhalation, many of these materials may act as skin irritants or may be toxic by absorption through the skin. Chemicals can also be ingested, although this is not usually the principal route of entry into the body. 

Among the major potential hazards affecting working environment are chemical (airborne contaminants), biological, and physical hazards,. ir contaminants are commonly classified as either particulate contaminants or gas and vapor contaminants. Common particulate contaminants include dusts, fumes, mists, aerosols, and fibers. 

As discussed in Chapter 4, chemicals can be a nuisance or pose health risks if they become airborne as a result of inadequate process control, operation and maintenance malpractice, inadequate maintenance, incomplete understanding of the process etc. Hazards may arise if the oxygen concentration in the air fluctuates beyond its normal level of 21% by volume, and fire/explosion dangers may arise from the presence of flammable gases, vapours or dusts in the atmosphere. Thus air quality tests may be required for a variety of purposes such as ... 

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