Explosives safety precautions

General Safety Precautions. The preparation and handling of the items covered by this specification, and the subassemblies thereof, involve hazardous operations and therefore require explosives safety precautions. Use of this specification will not be construed as to relieve the contractor or manufacturer of responsibility for the safety of his operations. Listed below are certain minimum provisions which a contractor or manufacturer (who prepares the item covered) should observe in order to fulfill his responsibility for safety. At Bureau of Naval Weapons, Navy Department, and other government plants, these provisions are mandatory. Such other warnings and precautions, pertinent to the operational effectiveness or safety during preparation of the specified items, are included in detailed technical requirements of the specification... 

D. P. Donegan, "Trends ia Electrostatic Precautions ia Filling Factories," ia Minutes of the 17th Explosives Safety Seminar, AD A036015, DDC, 1976. 

Cross-country gas pipelines generally must odorize the normally odorless, colorless, and tasteless gas ia urban and suburban areas, as is required of gas distribution companies. Organosulfur compounds, such as mercaptans, are usually used for this purpose, and code requires that the odor must be strong enough for someone with a normal sense of smell to detect a gas leak iato air at one-fifth the lower explosive limit of gas—air mixtures. The latter is about 5%, so the odorant concentration should be about 1%, but most companies odorize more heavily than this as a safety precaution. 

Fig. 20-4 Safety precautions for water tanks (a) and filter tanks (b) to prevent danger of explosion from hydrogen.

An explosion and fire (March 13, 1991) occurred at an ethylene oxide unit at Union Carbide Chemicals Plastics Co. s Seadrift plant in Port Lavaca, TX, 125 miles southwest of Houston. The blast killed one, injured 19, and idled the facility, that also produces ethylene, ethylene glycol, glycol ether ethanolamines, and polyethylene. Twenty-five residents were evacuated for several hours as a safety precaution. The plant lost all electrical power, for a few days, because its cogeneration unit was damaged. The Seadrift plant, with 1,600 workers, is capable of making 820 million lb per year of ethylene oxide which is one-third of Carbide s worldwide production of antifreeze, polyester fibers, and surfactants Seadrift produces two thirds of Carbide s worldwide production of polyethylene. 

The submitters concentrated the reaction mixture by vacuum distillation (100 mm, bath temperature 70°C, vapor temperature 51°C). The weight after concentration was ca. 120 g. The checkers used rotary evaporation with a bath temperature of 65 to 70°C without any problems, and employed an explosion shield as a safety precaution. 

Hazard, i.e. the potential of the material to cause injury under certain conditions (flammability, explosion limits in air, ignition and autoignition temperatures, static electricity (explosions have occurred during drying due to static electricity), dust explosion, boiling point, fire protection (specification of extinguishers, compounds formed when firing), R S (nature of special risk and safety precautions). Table 5.2-5 lists hazards associated with typical chemical reactions. 

Since pentane is a flammable gas that can form explosive mixtures in combination with air or oxygen, suitable safety precautions must be taken. 

During pyrolysis to silver (via silver dicyanamide), initial heating must be slow to avoid explosion [1], High intensity illumination will also cause explosive decomposition of a confined sample [2], Safety precautions for preparation and subsequent use of the explosive salt are detailed [3],... 

Severe explosions occurred when the cold crystalline solid was allowed to warm to ambient temperature. Normal manipulation of dilute solutions appears feasible, but the solid must be handled at lowest possible temperatures with full safety precautions. The 4-isomer appears much more stable. 

A strong oxidant, mixtures with both organic and inorganic compounds are potentially explosive. It is recommended that the synthesis be not scaled up and be performed with due safety precautions. 

It is a powerful explosive [1] produced when xenon tetrafluoride or xenon hexafluoride are exposed to moist air and hydrolysed. Some tetrafluoride is usually present in xenon difluoride, so the latter is potentially dangerous. Although safe to handle in small amounts in aqueous solution, great care must be taken to avoid solutions drying out, e.g. around ground stoppers [2], Full safety precautions have been discussed [2,3,4], Precautions necessary for use of aqueous solutions of the trioxide as an epoxidation reagent are detailed [5,6], A safe method of preparation,... 

A typical approach for safety precautions to be taken to prevent fires and explosions in handling solid materials is presented by Reay [219]. 

With proper safety precautions and operating procedures the occurrence of explosions in the vapor space of fixed roof storage tanks are a very rare event. A frequency estimate of an explosion once in every 1,000 years, per tank, has been stated. Explosive mixtures may exist in the vapor space of a tank unless precautions are taken. Any vapor will seek an ignition source, so prevention of ignition cannot be guaranteed. This is especially true with liquids that have low conductivity that... 

An important factor in the use of propene is the fact that explosive concentrations of the gas are reached well before any physiological changes occur, and the gas or compressed liquid should be handled according to strict safety precautions. 

The distillation is not carried to completion because of the resulting danger of explosion. It is carried out with the usual safety precautions (safety shield), although no explosion has yet occurred. 

Warning Formulas in this book relate to mixtures, some or all of which may be highly volatile and could react violently if ignited by heat, spark, or friction. High-energy mixtures should be prepared or handled by anyone untrained in proper safety precautions work in connection with pyrotechnics and explosives... 

Safety Precautions. Fixed and Semi-fixed ammunition should never be dropped, rolled or thrown, and as long as this is observed, there is little danger in handling it Refs 1) US Army Chief of Ordnance, "Safety and Storage Manual for Explosives and Ammunition", OO Form No 5994, Washington,... 

Nitroethanol prepared by the formaldehyde-nitromethane method should not be distilled without use of diphenyl ether as a heat-dispersing agent. The residue, consisting of di- and tricondensation products of formaldehyde with nitromethane, when hot and concentrated, and particularly when the vacuum is broken and air is let in on the hot distillation residue, is very likely to undergo a flash detonation, or at least a fume-off which may proceed with explosive violence. Use of diphenyl ether is a wise safety precaution in the distillation of 2-nitroethanol made by other methods as well. 

The tubes are extruded from the hot material, under high pressure (200-700 kg/cm2) using hydraulic presses, with the cylinders heated with hot water to a temperature of 90°C. Since the pressing operation is rather dangerous and sometimes leads to explosion, the cylinders are usually fairly small and hold at most 10-25 kg of paste. As a safety precaution the press should be separated by a wall from the conveyor... 

As a safety precaution against EXPLOSION (in case the purification has been insufficiently thorough) at least a quarter of the total volume of ether should remain in the distilling flask when the distillation is discontinued. To minimize peroxide formation, ethers should be stored in dark bottles and, if they are liquids, they should be left in contact with type 4A Linde molecular sieves, in a cold place, over sodium amalgam. The rate of formation of peroxides depends on storage conditions and is accelerated by heat, light, air and moisture. The formation of peroxides is inhibited in the presence of diphenylamine, di-tert-butylphenol, or other antioxidant as stabilizer. 

Perchloryl fluoride generally reacts with electron-rich alkencs or with various carbanionie substrates (Scheme 1), where salts are usually prepared in situ and further react at low temperature or in some cases at room temperature temperature control must be taken into account. However. it has been pointed out several times that serious explosions may occur and for this reason the reactions are potentially hazardous and safety precautions must be taken when working with this reagent. Over the last twenty years fluorination reactions with perchloryl fluoride have been partially discussed in several monographs6 8 and review papers.9 12... 

Trifluoromethyl hypofluorite is generally used at low temperatures with reactants dissolved in an inert solvent, but to increase the solubility of reactants a cosolvent (MeOH, acetone, THF) is often used however, it must be used with extra caution and appropriate safety precautions against explosions and fires, since trifluoromethyl hypofluorite is a powerful oxidizing agent. The toxicity of trifluoromethyl hypofluorite is expected to be high (as with fluorine). Fluori-nation reactions with trifluoromethyl hypofluorite have been discussed in the last twenty years in review papers6 11,65 and several monographs.12" 14... 

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