Hazardous Chemical Determination

Consider a substance as hazardous if regulated by OSHA in 29 CFR Parts 1910, Subpart Z. Treat any substances included in the latest edition of the ACGIH Documentation of the Threshold Limit Values and Biological Exposure Indices as hazardous. Any substance confirmed or suspected to be 

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Chlorine was placed second in a priority list ranking of hazardous chemicals determined by the Emergencies Branch of Environment Canada (Fingas et al., 1991). Some of the criteria used in ranking chemicals are historical spill volume, supply volume, reported spUl frequencies, and toxicity, including persistence and bioaccumulation. This substance should therefore be of great concern. 

Understanding the chemistry of the process also provides the greatest opportunity in applying the principles of inherent safety at the chemical synthesis stage. Process chemistry greatly determines the potential impact of the processing facility on people and the environment. It also determines such important safety variables as inventory, ancillary unit operations, by-product disposal, etc. Creative design and selection of process chemistry can result in the use of inherently safer chemicals, a reduction in the inventories of hazardous chemicals and/or a minimization of waste treatment requirements. 

Bretherick s Handbook, NFPA 49, 325 and 432 hazard ratings, Sax, Handbook of Hazardous Chemical Properties, Kirk-Othmer Encyclopedia of Chemical Technology or as determined... 

Typical units for LDjq values are milligrams or grams of material per kilogram of body weight (mg/kg or g/kg, recall that 1 kg = 2.2 pounds). Never be exposed to an LD50 dose of a hazardous chemical- by definition, there is a 50% chance this will kill you and if you survive you are not going to be in good shape. Pay close attention to the permissible exposure level (PEL) instead. This is a more realistic determination of the maximum safe exposure to a material and is usually based on the known effects of the chemical on humans, rather than laboratory animals. 

Chemicals determined by the U.S.E.PA to be extremely hazardous to a community during an emergency spill or release as a result of their toxicibes and physical/chemical properties. 

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-... 

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. ... 

For a hazardous chemical mixmre tliat has been tested as a whole to determine its liazards, the chemical and common names of the ingredients tliat are associated with the hazards, mid tlie common name of the mixture must be listed. 

The purpose of this handbook is to facilitate, within the DOE, the performance of chemical process hazards analyses (PrHAs) as required under the PSM Rule. It provides basic information for the performance of PrHAs, and should not be considered a complete resource on PrHA methods. Likewise, to determine if a facility is covered by the PSM rule, the reader should refer to the handbook, "Process Safety Management for Highly Hazardous Chemicals" (DOE-HDBK-1101-96). 

Identification of hazardous chemicals through thermodynamic and kinetic analyses is discussed in Chapter 2. This hazard identification makes use of thermal analysis and reaction calorimetry. In Chapter 2, an overview of the theory of thermodynamics, which determines the reaction (decomposition)... 

Two substances which have no hazardous reactivity properties in themselves can become dangerous when mixed. Certain groups of chemicals are likely to react with common substances such as air, water, acids, alkalies, and metals. Information about the possibility of such reactions is available in manuals on hazardous chemical reactions [35, 61, 62]. Examples of substances having incompatibility hazards when mixed are shown on Table 2.14. Applications of CHETAH to mixture instability determination [63,64] and to binary incompatibility [65] have been published. 

In the first place, PSM and RMP require that all responsible parties survey their industrial complexes where covered chemical processes are employed and to closely scrutinize these processes to determine if any of the 130+ Highly Hazardous Chemicals listed in OSHA s PSM and/or if any of the 140+ Extremely Hazardous Substances listed in USEPA s RMP are stored, handled, used, or produced on-site (e.g., off-gases, etc.). 

In many of the chemical catastrophes of the past, compliance with PSM and RMP would have ensured that the affected processes/plants had been thoroughly surveyed for processes using or producing highly hazardous chemicals and extremely hazardous substances. This survey would have determined, of course, that the sites used covered chemicals in their process. Moreover, the survey would have noted the normal quantity of listed chemicals stored on the plant site at any given time. This survey would also have made note if any quantities of listed chemicals stored on the plant site exceeded the PSM and RMP threshold quantities (TQ). 

Background concentrations of suspected or tentatively identified hazardous chemical contaminants may be extremely important in determining if an incident has occurred. In some cases, and for some hazardous chemicals, background levels may be at detectable concentrations. Baseline occurrence information is derived from monitoring data and is used to characterize typical levels of a particular chemical contaminant. 

If you are exposed to a hazardous chemical such as bromomethane, several factors will determine whether harmful health effects will occur and what the type and severity of those health effects will be. These factors include the dose (how much), the duration (how long), the route or pathway by which you are exposed (breathing, eating, drinking, or skin contact), the other chemicals to which you are exposed, and your individual characteristics such as age, sex, nutritional status, family traits, life style, and state of health. 

The fact that we are all continuously exposed to many different chemicals Is because the law allows this to happen. European law Is currently based on an assumption that there are acceptable levels of risk, even from the most hazardous chemicals, and regulators determine acceptable levels of exposure from these risk calculations. 

The complexity of the plant design, the degree of sophistication, and the quality requirements of the fine chemicals to be produced the necessity to process hazardous chemicals the sensitivity of product specifications to changes of reaction parameters and the availability of a skilled workforce all determine the degree of automation that is advisable. 

The work described here was performed in a laboratory which had been specially modified and equipped to handle chemical carcinogens (10). Strict care was taken to avoid worker exposure to hazardous chemicals during the course of these studies. Reagent grade chemicals used for this work were 1,2-dichloroethane (Alfa Products, Danvers, MA) 1,1,1-trichloroethane (Matheson, Coleman Bell, Norwood, OH) 1,1,2-trichloroethane (J.T. Baker Chemical Co., Phillipsburg, NJ) n-heptane and n-hexane (Burdick Si Jackson Laboratories, Inc., Muskegon, MI). Also,used was a polychlorinated biphenyl whose chemical composition as determined... 

Data on exposure and environmental fate are needed, not to determine toxicity, but to provide information that may be useful in the prediction of possible exposure in the event that the chemical is toxic. These tests are primarily useful for chemicals released into the environment such as pesticides, and they include the rate of breakdown under aerobic and anaerobic conditions in soils of various types, the rates of leaching into surface water from soils of various types, and the rate of movement toward groundwater. The effects of physical factors on degradation through photolysis and hydrolysis studies and the identification of the product formed can indicate the rate of loss of the hazardous chemical or the possible formation of hazardous degradation products. Tests for accumulation in plants and animals and movement within the ecosystem are considered in Section 21.7. 

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