Hazardous materials defined

Permissible exposure limit (PEL) (safety) Permissible exposure limits to hazardous materials (defined by the OSHA). See also Short-term exposure limit (STEL) Time-weighted average (TWA). 

Introduction The meaning o hazard is often confused with risk. Hazard is defined as the inherent potential of a material or activity to harm people, property, or the environment. Hazard does not have a probability component. 

Nadeau, R., J. Lafornara, G. Klinger and T. Stone. Measuring Soil Vapors for Defining Subsurface Contaminated Plumes. Management of Uncontrolled Hazardous Waste Sites Proceedings, Hazardous Materials Control Research Institute, Washington, D.C., 1985. 

What do we mean when we speak of an inherently safer chemical process Inherent has been defined as existing in something as a permanent and inseparable element, quality, or attribute (American College Dictionary, 1967). A chemical manufacturing process is inherently safer if it reduces or eliminates the hazards associated with materials and operations used in the process, and this reduction or elimination is permanent and inseparable. To appreciate this definition fully, it is essential to understand the precise meaning of the word hazard. A hazard is defined as a physical or chemical characteristic that has the potential for causing harm to people, the environment, or property (adapted from CCPS, 1992). The key to this definition is that the hazard is intrinsic to the material, or to its conditions of storage or use. Some specific examples of hazards include ... 

There are many sehools of thought on the use of PPE. We will outline and define some of the most important PPEs that should be used when dealing with hazardous materials. 

Originally the classification of materials was derived from tests of proprietary explosion-proof (flameproof) enclosures. There were no published criteria. Equipment was approved relative to the lowest ignition temperature of any material in the group (Magison 1987). In about 1965 the U.S. Coast Guard asked the National Academy of Sciences (NAS) to form a panel to classify 200 materials of commerce. The Electrical Hazards Panel of the Committee on Hazardous Materials was formed by the NAS. The Panel studied many ways to estimate the hazard classification of materials. The Panel finally reported to die U.S. Coast Guard in 1970 that no workable, predicdve scheme could be defined, and it then proceeded to assign tentative classifications to the 200 materials. 

The Hazardous Materials Transportation Act (HMTA) defines transportation releases to be those that occur during loading, unloading, transportation or temporary storage of hazardous materials or waste. Releases that meet certain criteria (see Table 64.1) should be reported to the National Response Center (NRC) and the state response center. Most states also require calls to the local police or response agencies (often by calling 911). Follow-up writ-... 

RCRA was passed to manage nonhazardous and hazardous wastes and underground storage tanks, with an emphasis placed on the recovery of reusable materials as an alternative to their disposal. This act introduced the concept of the separate management of hazardous and nonhazardous wastes, and defined procedures to identify whether a waste is hazardous or nonhazardous. A waste exhibits the characteristic of toxicity, classified as a hazardous material, if the concentration of any of 39 selected analytes in the Toxicity Characteristic Leaching Procedure (TCLP) extract exceed regulatory action levels. 

The sources of contamination are usually those hazardous materials that are contained in drums, tanks, surface impoundments, waste piles, and landfills, as well as heavily contaminated media (such as soil) affected by the original leaking or spilling source. The purpose of defining sources of contamination is to help to identify the source location, potential releases, and engineering characteristics that are important in the evaluation of remedial actions, as well as waste characteristics, such as the type and quantity of contaminants that may be contained in or released to the environment, and the physical or chemical characteristics of the hazardous wastes present in the source. 

Technical Paper Defining the Operating Conditions for the Incineration of the Chemical Agents GB, H, and VX. U.S. Army Toxic and Hazardous Materials Agency, 7 May 1984. 

Contingency Plan A pre-planned document presenting an organized and coordinated plan of action to limit potential pollution in case of fire, explosion or discharge of hazardous materials which defines specific responsibilities and tasks. 

National Contingency Plan Created by CERCLA to define the federal response authority and responsibility for oil and hazardous materials spills. The regulations are codified at 40 CFR300. 

Dangerous goods" is defined in the context of recommended international hazardous material transportation regulations. The UN "Orange Book" should be consulted for further information on the definition of dangerous goods for transportation purposes (UN 2002). 

Here we are concerned with chemical industry (including hazardous materials) infrastructure, which we define as follows ... 

Other kinds of electrical equipment may also be used in hazardous locations. One kind is purged and pressurized electrical equipment. This equipment works by using air or nonflammable protective gas flow or pressure to prevent hazardous materials from entering the enclosure NFPA 496 defines three types of purged and pressurized equipment as identified in Table 7-5. 

Another kind of electrical equipment suitable for use in hazardous locations is equipment whose maximum possible energy output is insufficient to ignite the hazardous material. The electrical input to this equipment must be controlled by a specially designed electrical barrier. Such electrical equipment must be compatible. ANSI/UL913 defines low energy intrinsically safe electrical equipment and associated apparatus permitted in Division 1 areas. Nonincendive electrical equipment is permitted in Division 2 locations. Table 7-6 describes intrinsically safe and nonincendive equipment and identifies permitted uses. 

Federal and State laws define waste as hazardous if it is ignitable, corrosive, reactive, or toxic. Other wastes are listed by name. These may differ from lists of hazardous materials, which are regulated by OSHA and Right-to-Know. The Standard Industrial Classifications (SICs) of a physician s medical office and a dentist s office are 8011 and 8021, respectively. 

NFPA Hazard Classifications — The indicated ratings are given in "Fire Protection Guide on Hazardous Materials," National Fire Protection Association. The classifications are defined in Table 1. 

The following is a list of chemicals and articles that are regulated by the U.S. Department of Transportation. The information has been obtained from 49 CFR, Parts 100-177 (.Hazardous Materials Table). The articles and chemicals are grouped by the hazard class and division (as defined in Chapter 1). 

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