Safety Topics

Rapid Methods For Healthcare – The Options

While there are classes of chemicals that in themselves may be reactive, there are also stable chemicals which are not reactive but when combined may interact, resulting in an explosive reaction. Good sources for information about chemical interactions are Bretherick , Sax , and the U.S. Mixing incompatible materials may result in the formation of unstable/reactive materials; therefore, the literature search should document incompatible materials. In addition to discrete chemicals, it should be realized that certain dusts might be combustible and explosive, such as that produced by bakeries, sawmills, and in grain handling.

A problem with the use of common names or abbreviations is that they may be used for more than one molecular entity. For example, TCE is sometimes used as an acronym for tetrachloroethylene, although it more frequently refers to trichloroethylene. To avoid confusion, literature is often indexed using the CAS number or the primary chemical name. An example of the type of chemical identification data that is needed is presented for Perclene®, a widely used industrial solvent.

Many agents will burn when ignited whereas there are only a few that will spontaneously erupt into flames. While no single measure of flammability is sufficient for all purposes, the most commonly found measure in the literature is the flashpoint. For this reason, HCS uses flashpoint in classifying the fire hazard of a chemical. In the remainder of this section, an overview is presented of the HCS designated hazards and their definitions. In addition, a brief discussion is presented to further explain the specific hazard as well as procedures that can be used to analyze the data.

Perclean® is a trade name for perchloroethylene or Perc , or more specifically tetrachloroethylene (CAS Number ). Thus, the most effective search of computerized databases is conducted using tetrachloroethylene and/or CAS Number .

The chemical composition information should be based on an analysis of the final or technical product. A technical grade product is not usually a pure substance and often contains other chemicals such as stabilizers, solvents, carriers, “inert” ingredients, or impurities. For the hazard evaluation process, these other chemicals must also be listed if they are more than 1.0% of the composition for non-carcinogenic substances or 0.1% of the product if the substance is a carcinogen. Correct identification of chemicals is critical for data retrieval. Use the precise chemical name and CAS number when searching for information.

The other major measure of statistical significance is the 95% confidence level for a specific data point. Most reports of toxicity testing will include some information on the confidence in the data. There are three key criteria that must be met, namely “statistically significant”, “positive study”, and “established scientific principles”. Thus, the evaluation of study results requires some knowledge of statistics, commonly accepted scientific test methodology, and the definitions of health hazards. The percent composition should be available in-house for all chemicals and products manufactured or imported.

  • Hazard determination is the process of evaluating available scientific evidence in order to determine if a chemical is hazardous pursuant to the HCS.
  • The hazard determination provides the basis for the hazard information that is provided in MSDSs, labels, and employee training.
  • This evaluation identifies both physical hazards (e.g. , flammability or reactivity) and health hazards (e.g. , carcinogenicity or sensitization).

Because this document can only present a limited discussion of the various hazards, you are encouraged to consult references that go into greater detail . Most toxicity and epidemiology reports will provide an analysis of the data and conclude whether the results were positive or negative, or will describe the adverse effects observed at specific dose levels. Positive results mean that the exposed humans or animals were more likely to develop toxic effects than the non-exposed population.

Where data indicating the flashpoint of a chemical are not available, you may choose to test the chemical to determine the flashpoint. The ability of a chemical to either burn or support burning is a potentially disastrous physical hazard. The two primary measures of the ease with which a liquid will burn are the flashpoint and autoignition temperature. The flashpoint is the lowest temperature at which a liquid will emit sufficient vapors to form an ignitable mixture with air. In contrast, autoignition is the characteristic of a material in which it will spontaneously burn without the aid of an ignition source, such as a spark or flame.

A Guide To Practical Plans For Health Life

Similarly, a mixture will not be categorized as a flammable liquid if it is composed of at least 99% of components with flashpoints above 100ºF (38ºC). Many mixtures will contain more than 1% of a flammable liquid and the mixture will have a flashpoint above 100ºF allergy symptoms.

Many of these are elements (e.g. , lithium, powdered aluminum, magnesium) or organometallic compounds . Moisture in the air often increases the probability of spontaneous ignition of pyrophoric materials. A mixture will not be categorized as a combustible liquid so long as less than 1% of the total volume of components have flashpoints between 100º and 200ºF. For example, if Chemical A has a flashpoint of 180ºF and represents 0.5% of the mixture and all other chemicals have flashpoints above 200ºF, then the mixture is not considered a combustible liquid.

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