Explosive chemicals handling procedures

Testing procedures are available to determine if peroxides have formed by sampling outsides of containers however, they should only be conducted by persons with a chemical background and experience with the test procedures. The precautions taken for disposal of these materials should be the same as for any material that can be detonated by friction or shock. In general, the material should be carefully removed, using explosive handling procedures. 

Chlorine trifluoride reacts vigorously with water and most oxidizable substances at room temperature, frequently with immediate ignition. It reacts with most metals and metal oxides at elevated temperatures. In addition, it reacts with silicon-containing compounds and thus can support the continued combustion of glass, asbestos, and other such materials. Chlorine trifluoride forms explosive mixtures with water vapor, ammonia, hydrogen, and most organic vapors. The substance resembles elemental fluorine in many of its chemical properties and handling procedures, which include precautionary steps to prevent accidents. 

To avoid or minimise accidents in the chemical laboratory, such as fires and explosions, and to ensure that students and staff are not exposed to odier health hazards, they should be aware of the risks involved in handling chemicals and in carrying out reactions. In addition, they should know the measures required to deal widi hazardous situations. They should be familiar with the use and situation of fire extinguishers, protective blankets, eye wash facility, first aid box, as well as evacuation procedure in case of fire or explosion. Chemicals manufacturers are obliged by law to label all hazardous chemicals with a warning sign to indicate the type of hazard. When chemicals are dispensed in containers other than those supplied by manufacture, these containers should be also clearly labelled for the possible hazards. 

Tables 16 and 17 Hst tke analytical test methods for different properties of interest. The Manufacturing Chemists Association, Inc. (MCA) has pubUshed the Chemical Safety Data Sheet SD 63, which describes in detail procedures for safe handling of use of toluene (46). The Interstate Commerce Commission classifies toluene as a flammable Hquid. Accordingly, it must be packaged in authorized containers, and shipping must comply with ICC regulations. Properties related to safe handling are autoignition temperature, 536°C explosive limits, 1.27—7.0 vol % in air and flash point 4.4°C, closed cup.

Many analytical and other chemical procedures can be hazardous if handled carelessly, and explosive samples can cause potentially dangerous accidents in many methods of elemental chemical analysis)... 

An MSDS lists the hazardous chemical contents of a product, describes its health and safety hazards, and gives methods for its safe use, storage, and disposal. The MSDS also includes information on fire and explosion hazards, reactivity, first aid, and procedures for handling leaks and spills. 

Standard tests are utilized early in the evaluation phase to evaluate flammability, ignition and explosive characteristics. These include differential thermal analysis, thermo gravometric analysis, drop weight tests, friction tests, card gap (shock initiation) tests, and materials compatibility tests. Information derived from the above tests serve as a basis to establish safe procedures and techniques to handle and process the chemicals into propellants. 

Numerous problems remain to be solved before it will be possible to quantify the sensitivity of explosives to impact and friction in terms that express an intrinsic property of the chemical substances. The need for more refined tests, a better understanding of the phenomena that occur during the test procedures, and improved statistical approaches to the treatment of low-probability events are paramount requirements for more meaningful data. Even then it will continue to be difficult to relate measurements in laboratory apparatus to the conditions encountered in the industrial handling and field utilization of azides. 

Table 3 lists some common classes of laboratory chemicals that have potential for producing a violent explosion when subjected to shock or friction. These chemicals should never be disposed of as such, but shouldbe handled by procedures given in Prudent Practices for Disposal of Chemicals from Laboratories, National Academy Press, 1983, chapters 6 and 7. Additional information on these, as well as on some less common classes of explosives, can be found in L. Bretherick, Handbook of Reactive Chemical Hazards, 3rd ed., Butterworths, London-Boston, 1985. 

Laboratory hoods must be used for all procedures that might release hazardous chemical vapors or dusts. Wet chemistry for volatile substances—notably certain organic solvents and radionuclides—should be performed in a hood to reduce inhalation risks. Chemicals that pose a substantial risk of explosion must be handled in a hood designed to contain explosions. 

---