Hazardous chemical agents

Thus, there is a clear need to establish the relationship between the health effects of hazardous chemical agents in the environment and the level of occupational exposure to the body by means of an occupational exposure limit, in which a reference figure for the concentration of a chemical agent is set. In fact, occupational exposure limits (OELs) have been a feature of the industrialized world since the early 1950s. They were introduced, primarily in the United States, at a time when measures to prevent occupational diseases were considered more beneficial than compensating victims, and in this sense OELs have played an important part in the control of occupational illnesses. 

Determination and assessment of the risks of hazardous chemical agents requires knowledge of, among other things, the nature of the agents, the type and duration of the exposure, the gravity of risk, and the criteria chosen for the OEL. The purpose is to make quantitative measurements of the work environment in order to compare the exposure with the limit value by means of an independent scientific assessment using the best available scientific methodol-... 

The employer shall ensure that the risk from a hazardous chemical agent to the health and safety of workers at work is eliminated or reduced to a minimum. 

In applying paragraph 1, substitution shall by preference be undertaken, whereby the employer shall avoid the use of a hazardous chemical agent by replacing it with a chemical agent or process which, under its condition of use, is not hazardous or less hazardous to workers health and safety, as the case may be. 

Exposure to hazardous chemical agents can occur in the home, workplace, and in the community and may arise accidentally or through the intentional acts of terrorists. 

Hazards, chemical agent. See Chemical agent hazard. 

Concerning the physical-chemical risks, the employer has to take technical and organizational actions on the basis of the risk assessment in order to protect workers from fire and explosion hazards. The type of measures depends on the nature of the hazardous chemical agents and should be appropriate to the operation, including storage, handling, and segregation of incompatible materials. In order of priority the particular measures are... 

Procedure in case of leakage. If hazardous chemical agents are released because of damage to a container, the supervisor must be informed immediately. AU subsequent actions must be in accordance with written instructions and the alarm plan. 

It only adsorbs nerve and mustard agents various coating resins need to be developed to absorb different individual types of hazardous chemical agents. 

The European directive on the protection from chemical hazards illustrates a more systematic approach in the application of the barrier philosophy to prevent occupational accidents and diseases (European Council, 1998). To prevent workers from being exposed to hazardous chemical agents, the employer must take actions in a priority from left to right according to Figure 7.2. 

Qccupational Safety and Health Administration (QSHA) (1992). 29 CFR Part 1910. Process Safety Management of Highly Hazardous Chemicals Explosives and Blasting Agents Final Rule. Federal Register 57, 36 (February 24), 6356-417. 

This is a subroutine that calculates an evaporation rate from a pool of spilled liquid in presence of wind (ORG-40), or in still air (TP-10). It was developed by the U.S. Array for downwind hazard prediction following release from smoke munitions and chemical agents. The code calculates the evaporation rate of a liquid pool, given the physical stale variables, wind speed, and diameter of pool. ORG-40 and TP-10 models are coded as a Fortran 77 subroutine, EVAP4.FOR, in D2PC. The user s manual is Whiiacre (1987). 

The first step is to identify the substances present at the workplace. As a starting point, knowledge of the process is needed in order to formulate a list of all chemical agents used in the establishment. The list should include not only primary products but also intermediate and final products, as well as reaction products and by-products. For the chemical agents in the list, it is necessary to know their chemical properties, especially hazardous ones their OEL values, including biological limit values and, where these are not available, other technical criteria that can be used to evaluate the risk. It is also helpful to include any information on the safety and health risks of those substances provided by the supplier or other readily available sources. This information on dangerous substances and preparations, in the form of safety data sheets, is intended primarily for industrial users, to enable them to take the measures necessary to ensure the safety and health of workers. 

Exposure limits Guidelines for worker exposure to physical agents and hazardous chemicals, usually expressed as an allowable time of exposure or an air concentration below which health hazards are unlikely to occur among most exposed workers. 

Hazard identification is defined as tlie process of determining whetlier human exposure to an agent could cause an increase in the incidence of a health condition (cancer, birtli defect, etc.) or whetlier exposure to nonliumans, such as fish, birds, and otlier fonns of wildlife, could cause adverse effects. Hazard identification cliaracterizes tlie liazard in terms of tlie agent and dose of the agent. Since tliere are few hazardous chemicals or hazardous agents for wliich definitive exposure data in humans exists, tlie identification of health hazards is often characterized by the effects of health hazards on laboratory test animals or other test systems. ... 

These iiicchanisnis can affect the near-term and ultimate fate of a chemical hazard. Recognition of these inechanisms can significantly assist in the identification of a chemical agent as a health hazard. In recent years, the understanding of chemical transport, chemical manipulation in the body, and response by animals luid humans to cheniicals has advtmccd to a point where it is possible to determine whether a chemical is indeed a health hazard. 

Aggregate the hazard for multiple chemical agents and exposure pathways as a hazard index, where appropriate. 

Hazard characterization is a quantitative or semi-quantitative evaluation of the nature, severity, and duration of adverse health effects associated with biological, physical, or chemical agents that may be present in food. The characterization depends on the nature of the toxic effect or hazard. Eor some hazards such as genotoxic chemicals, there may be no threshold for the effect and therefore estimates are made of the possible magnitude of the risk at human exposure level (dose-response extrapolation). 

Buchanan MV, Hettich RL, Xu JH. 1995. Low level detection of chemical agent simulants in meat and milk by ion trap mass spectrometry. Journal of Hazardous Materials 42 49-59. 

Pal T, Griffin GD, Miller GH, et al. 1993. Permeation measurements of chemical agent simulants through protective clothing materials. Journal of Hazardous Materials 33(1) 123-141. 

OSHA. 1991. Process safety management of highly hazardous chemicals explosives and blasting agents. Occupational Safety and Health Administration. Federal Register 57(36) 6356. February 24, 1991. 

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