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Safety carbon tetrachloride

The various fumigants often exhibit considerable specificity toward insect pests, as shown in Table 8. The proper choice for any control operation is determined not only by the effectiveness of the gas but by cost safety to humans, animals, and plants flammabdity penetratabdity effect on seed germination and reactivity with furnishings. The fumigants may be used individually or in combination. Carbon tetrachloride has been incorporated with carbon disulfide, ethylene dichloride, or ethylene dibromide to decrease flammability, and carbon dioxide is used with ethylene oxide for the same purpose. [Pg.298]

If an ethyl ether fire occurs, carbon dioxide, carbon tetrachloride, and dry chemical fire extinguishers meeting National Eire Prevention Association Code 1 and 2 requirements may be used successhiUy (23). Water may also be effectively appHed (see Plant safety). Hose streams played into open tanks of burning ethyl ether serve only to scatter the Hquid and spread the fire. However, ether fires may be extinguished by a high pressure water spray that cools the burning surface and smothers the fire. Automatic sprinklers and deluge systems are also effective. [Pg.428]

The most critical decision to be made is the choice of the best solvent to facilitate extraction of the drug residue while minimizing interference. A review of available solubility, logP, and pK /pKb data for the marker residue can become an important first step in the selection of the best extraction solvents to try. A selected list of solvents from the literature methods include individual solvents (n-hexane, " dichloromethane, ethyl acetate, acetone, acetonitrile, methanol, and water ) mixtures of solvents (dichloromethane-methanol-acetic acid, isooctane-ethyl acetate, methanol-water, and acetonitrile-water ), and aqueous buffer solutions (phosphate and sodium sulfate ). Hexane is a very nonpolar solvent and could be chosen as an extraction solvent if the analyte is also very nonpolar. For example, Serrano et al used n-hexane to extract the very nonpolar polychlorinated biphenyls (PCBs) from fat, liver, and kidney of whale. One advantage of using n-hexane as an extraction solvent for fat tissue is that the fat itself will be completely dissolved, but this will necessitate an additional cleanup step to remove the substantial fat matrix. The choice of chlorinated hydrocarbons such as methylene chloride, chloroform, and carbon tetrachloride should be avoided owing to safety and environmental concerns with these solvents. Diethyl ether and ethyl acetate are other relatively nonpolar solvents that are appropriate for extraction of nonpolar analytes. Diethyl ether or ethyl acetate may also be combined with hexane (or other hydrocarbon solvent) to create an extraction solvent that has a polarity intermediate between the two solvents. For example, Gerhardt et a/. used a combination of isooctane and ethyl acetate for the extraction of several ionophores from various animal tissues. [Pg.305]

Safety aspects of the preparation from halotrinitromethanes or tetranitromethane by treatment with methyl iodide are improved by use of an aprotic solvent (DMF, DMSO or HMPA) in diethyl ether or carbon tetrachloride at 30-60°C. [Pg.293]

S2C12, a by-product in the manufacture of carbon tetrachloride from carbon disulphide. Was used, dissolved in solvent naphtha, in the vulcanising of mbber by the cold cure process and the vapour cure process. The process was fraught with health and safety problems and has been superseded by low temperature accelerators and room temperature vulcanising (RTV) systems for silicone and polyurethane. [Pg.62]

The toxicity of all the chemicals you will be working with must be known. Consult the instructor, material safety data sheets (MSDSs), safety charts, and container labels for safety information about specific chemicals. Recently, many common organic chemicals, such as benzene, carbon tetrachloride, and chloroform, have been deemed unsafe. [Pg.554]

National Institute for Occupational Safety and Health Criteria for a Recommended Standard. . . Occupational Exposure to Carbon Tetrachloride. DHEW (NIOSH) Pub No 76-133, pp 15-68, 84—112. Washington, DC, US Government Printing Office, 1975... [Pg.128]

People who work with carbon tetrachloride are likely to receive the greatest exposure to the compound. The National Institute for Occupational Safety and Health (NIOSH) estimates that 58,208 workers are potentially exposed to carbon tetrachloride in the United States. The average daily intake of carbon tetrachloride for the general population is estimated to be 0.1 microgram (pg). The estimated average daily amount that the general population may drink in water is 0.01 pg. [Pg.13]

The purpose of this chapter is to describe the analytical methods that are available for detecting, and/or measuring, and/or monitoring carbon tetrachloride, its metabolites, and other biomarkers of exposure and effect to carbon tetrachloride. The intent is not to provide an exhaustive list of analytical methods. Rather, the intention is to identify well-established methods that are used as the standard methods of analysis. Many of the analytical methods used for environmental samples are the methods approved by federal agencies and organizations such as ERA and the National Institute for Occupational Safety and Health (NIOSH). Other methods presented in this chapter are those that are approved by groups such as the Association of Official Analytical Chemists (AOAC) and the American Public Health Association (APHA). Additionally, analytical methods are included that modify previously used methods to obtain lower detection limits, and/or to improve accuracy and precision. [Pg.129]

Burkhart KK, Hall AH, Gerace R, et al. 1991. Hyperbaric oxygen treatment for carbon tetrachloride poisoning. Drug Safety 6 332-338. [Pg.152]

NIOSH. 1975. Occupational exposure to carbon tetrachloride. Washington, DC National Institute for Occupational Safety and Health, Department of Health, Education, and Welfare. [Pg.176]

Since any material that will burn at any temperature is combustible by definition, it follows that this word covers all such materials, irrespective of their ease of ignition. Thus the term flammable actually applies to a special group of combustible materials that ignite easily and burn rapidly. Some materials (usually gases) classified in shipping and safety regulations as nonflammable are actually noncombustible. The distinction between these terms should not be overlooked. For example, sodium chloride, carbon tetrachloride and carbon dioxide are noncombustible sugar, cellulose and ammonia are nonflammable... [Pg.361]

In a well-ventilated hood, behind a safety shield, a suspension of 14.8 gm (0.145 mole) of anhydrous sodium acetate and 40 ml of dry carbon tetrachloride is cooled to below —10°C in a Dry Ice-acetone bath. With vigorous stirring, 4.00 gm (60 mmoles) of nitrosyl chloride is added. When the mixture has reached —10°C or lower, with vigorous stirring a solution of 40 mmole of the ketimine in 10 ml (or more if necessary) of dry carbon tetrachloride, which has previously been cooled to —10°C, is added at such a rate that the internal temperature in the apparatus is maintained at —7°C or below. Stirring of the dark reaction mixture is continued for 20 min at —10°C. [Pg.231]

In a well-ventilated hood, behind a safety shield, to a stirred solution-of 523.6 mg (4.00 mmoles) of IV-acetyl-O-t-butylhydroxylamine and 0.48 ml of dry pyridine in 6 ml of carbon tetrachloride, cooled to — 10°C, is added drop-wise a saturated solution of nitrosyl chloride in 12 ml of carbon tetrachloride. After addition of the nitrosating agent has been completed, the reaction mixture is stirred for an additional hour at -10°C. Then, while maintaining the system at 0°C, the reaction mixture is washed in turn with 25 ml portions of water, a 10 % aqueous solution of hydrochloric acid, a 10 % solution of sodium bicarbonate solution, and finally with water again. The organic layer is separated and dried over anhydrous magnesium sulfate. [Pg.232]

CAUTION Carbon tetrachloride is toxic by inhalation and skin contact and is a possible human carcinogen, and operations should be performed in a well-ventilated fume hood using appropriate safety precautions and procedures. [Pg.134]

A few oilier inorganic chemicals, more frequently identified as multipurpose pesticides than as insecticides, do have very strong insecticidal properties. These compounds are used sparingly, often requiring special permits in some places, and with the greatest of safety cautions observ ed. Such compounds would include calcium cyanide, carbon bisulfide, carbon tetrachloride, hydrogen cyanide, paraformaldehyde, and phosphine. [Pg.845]

The iodine value (IV) is used to determine the level of unsaturation in a fat/oil system. It is expressed as the number of grams of iodine that add to/react with 100 g of sample. The traditional iodine value method using the Wijs reagent requires carbon tetrachloride (CC14). For safety reasons, CC14 is no longer considered to be an acceptable chemical and it is not readily available for purchase, and if offered it is extremely expensive. Therefore the traditional method has been modified to a more human-friendly system which uses cyclohexane. [Pg.467]

Accdy to Bolt (Ref 1), ethylene (5.6 moles) was gradually introduced into a 2600-ml autoclave contg 17.6 moles carbon tetrachloride and 0.45 moles benzoyl peroxide, serving as reaction initiator. The pressure was kept below 2500psi. After about 2 hours an expln occurred at 67°, discharging most of the reactants thru the ruptured safety disk... [Pg.101]

Oxidizer, Poison, Corrosive SAFETY PROFILE Poisonous and corrosive. Very reactive, a powerful oxidizer. Explosive or violent reaction with organic materials, water, acetone, ammonium halides, antimony, antimony trichloride oxide, arsenic, benzene, boron, bromine, carbon, carbon monoxide, carbon tetrachloride, carbon tetraiodide, chloromethane, cobalt, ether, halogens, iodine, powdered molybdenum, niobium, 2-pentanone, phosphoms, potassium hexachloroplatinate, pyridine, silicon, silicone grease, sulfur, tantalum, tin dichloride, titanium, toluene, vanadium, uranium, uranium hexafluoride. [Pg.211]

DOT CLASSIFICATION 2.2 Label Nonflammable Gas SAFETY PROFILE Mildly toxic by inhaladon. Less chronically toxic than carbon tetrachloride. Violent reacdon with Al. When heated to decomposidon it emits toxic fumes of F". See also FLUORIDES. [Pg.290]

DOT CLASSIFICATION 4.1 Label Flammable Solid, Poison SAFETY PROFILE Poison by inhalation, ingestion, skin contact, and intraperitoneal routes. Ignites in O2 at 100°C. Forms impact-sensitive explosive mixtures with ethers (e.g., dioxane) and halocarbons (e.g., carbon tetrachloride). Incompatible with dimethyl sulfoxide. When heated to decomposition it emits toxic fumes of boron oxides. See also BORON COMPOUNDS and BORANES. [Pg.417]

DOT CLASSIFICATION 6.1 Label Poison SAFETY PROFILE Suspected carcinogen. Poison by ingestion and inhalation. Moderately toxic by skin contact. Human mutation data reported. A skin irritant. Action may be similar to that of carbon tetrachloride, but more irritating to mucous membranes. Flammable when exposed to heat, flame, or oxidizers. To fight fire, use alcohol foam, dry chemical, fog, mist, or spray. Dangerous when heated to decomposition it emits highly toxic fumes of CT and phosgene. [Pg.470]

SAFETY PROFILE Moderately toxic by skin contact, inhalation, intravenous, and intraperitoneal routes. Mildly toxic by ingestion. Experimental teratogenic and reproductive effects. A skin and eye irritant. Less toxic than dimethylformamide. Mutation data reported. Combustible when exposed to heat and flame. A moderate explosion hazard. Violent reaction with halogenated compounds (e.g., carbon tetrachloride, hexachlorocyclohexane) when heated above 90°C. Iron powder catalyzes the reaction so that it initiates at 71 °C. [Pg.519]


See other pages where Safety carbon tetrachloride is mentioned: [Pg.176]    [Pg.496]    [Pg.8]    [Pg.185]    [Pg.15]    [Pg.125]    [Pg.211]    [Pg.525]    [Pg.102]    [Pg.176]    [Pg.367]    [Pg.457]    [Pg.1369]    [Pg.130]    [Pg.130]    [Pg.82]    [Pg.123]    [Pg.457]    [Pg.695]    [Pg.71]    [Pg.37]    [Pg.844]    [Pg.1239]   
See also in sourсe #XX -- [ Pg.21 ]




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