Oxidizers hazards identification

Jim Skeaff and Pierrette King, Development of Data on the Reaction Kinetics of Nickel Metal and Nickel Oxide in Aqueous Media for Hazard Identification, Final Report, January 1998. Mining and Mineral Sciences Laboratories Division Report 97-089(CR)/Contract No. 51605... 

The health rating is provided on the left at the 9 o clock position and is colored blue. The flammability rating is provided at the top or 12 o clock position and is colored red. The reactivity hazard is provided on the right at the 3 o clock position and is colored yellow. The relative rankings for each hazard are indicated in each quadrant. Special hazard identifiers are provided in the bottom quadrant at the 6 o clock position, which is usually white. Special hazard qualifiers generally include radioactivity, explosives, corrosive, water reactive, oxidizer, etc. The NFPA fire hazard identification scheme is somewhat limited as it only identifies relative potential hazards with the individual material. It does not identify the material itself or all of its potential reactions with other materials. See Figure C.3 for a depiction of this placard. See also Chemical Hazard Label Hazardous Materials Identification System (HMIS ) NFPA 704, Standard System for the Identification of the Hazards of Materials for Emergency Response. 

The detection of new kinds of microorganisms, such as the cysts and oocysts of parasites (Giardia, Cryptosporidium), the identification of more and more chemical pollutants in waters and increasing quality levels required for drinking and waste waters has induced new interest in ozonation and ozone-based advanced oxidation processes. However, care has to be taken in the application of ozonation, since recent research has indicated that presumably hazardous by-products can be formed, e. g. bromate in the ozonation of waters containing bromide. 

Ammonium nitrate fertilizers that are not classified as oxidizers are classified as miscellaneous hazardous materials. This type of fertilizer has other materials in the mixture, and there are controlled amounts of combustible materials. Mixtures of ammonium nitrate, nitrogen, and potash that are not more than 70% ammonium nitrate and do not have more than 0.4% combustible material are included as a miscellaneous hazardous material. Additionally, ammonium nitrate mixtures with nitrogen and potash, with not more than 45% ammonium nitrate, may have combustible material that is umestricted in quantity. The four-digit UN identification number for these mixtures of ammonium nitrate fertihzer is 2071. 

Low Hazard Chenucals chemicals that have an NFPA flammability rating of 0 or 1 a health hazard rating of 0 or 1 a reactivity rating of 0 and no special hazard rating such as oxidizer , water reactive , or hazardous polymerization per NFPA 704, Identification System for Fire Hazards of Materials. 

Scope. As with gases, the avoidanee of mixing reactive chemieals is important. Chapter 5 of NFPA 318 eoneems itself with methods for storage and use of liquids and solids of a hazardous nature. NFPA uses the term Hazardous Chemicals and the Model Building Codes use Hazardous Production Materials. These are chemieals with speeified ratings of health, flammability, or reaetivity when tested in aceordanee with NFPA 704, Identification of the Fire Hazard of Materials. Flammable liquids and oxidizers are the two types of chemicals that present the greatest fire hazard in a cleanroom. 

For most flammable hydrocarbons, the LFL is around 2%—5%. For simple alkanes, such as methane and ethane, the UFL is in the 10%—15% range. Some chemicals, such as hydrogen, ethylene oxide, and acetylene, have much higher values for UFL. Values for flammable limit ranges for many flammable materials are provided by NFPA 704—Standard System for the Identification of the Hazards of Materials for Emergency Response. 

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