Explosion protection increased safety

Withdrawn) 1989 AMD 3 Code of practice for selection, installation and maintenance of electncal apparatus for use m potentially explosive atmospheres (other than mining applications or explosives processing and manufacture). Part 1 General recommendations (AMD 7871) dated 15 September 1993. Withdrawn, superseded by BS EN 60079-14 1997 (Withdrawn) 1978 AMD 1 Code of practice for selection, installation and maintenance of electncal apparatus for use m potentially explosive atmospheres (other than mining applications or explosives processing and manufacture). Part 6 Recommendations for type of protection. Increased safety (AMD 5557) dated 30 November 1989. Withdrawn, superseded by BS EN 60079... 

Rotating electrical machines starting performance of single-speed three-phase cage induction motors for voltages up to and including 690 V Electrical apparatus for explosive gas atmosphere. Increased safety protection e 8789/1996 6381/1991 BS EN 60034-12/1996 BS 5501-6/1977... 

The main field of application of oil immersion - o is the explosion protection of Group II transformers in the high power range (up to some 1000 kVA). The terminal compartments often comply with increased safety -e or plug and socket connectors (in e ) are used in the high voltage range (see Section 6.7). 

If safety programs have stalled on a plateau of acceptance, professionals should zero in on the causes of most work fatalities motor vehicle safety, truck fleet safety, workplace violence prevention, and fire and explosion protection (fatal work injuries resulting from fires and explosions rose from 113 in 2009 to 187 in 2010, an increase of 65 percent, according to the BLS. 

Common-cause failure of the DAS and the protection and safety monitoring system due to a fire or explosion could result in an unacceptable increase in risk of public or operator radiation exposure. The design solution effeetively decouples the two systems at an aceeptable eost, and it is therefore the ALARP option. 

Increased safety equipment is more akin to ordinary non-explosion-protected designs, but special precautions have to be taken to prevent any electrical or frictional sparking or hot spots exceeding the specified temperature limits. To prevent excessive heating the equipment is liberally rated and under fault conditions the associated control gear has to interrupt the circuit before dangerous overheating occurs. 

In the overcharge tests we carried out, there was no fire or explosion. The cell impedance increased suddenly in every test. This was due to the oxidation of the electrolyte with a low charging current, or to the separator melting with a high charging current. In practical applications, an electronic device should be used to provide overcharge protection and ensure complete safety. 

Underwriters Laboratories (UL) requires that consumer batteries pass a number of safety tests [3]. UL requires that a battery withstand a short circuit without fire or explosion. A positive temperature coefficient (PTC) device [4] is used for external short-circuit protection. The resistance of a PTC placed in series with the cell increases by orders of magnitude at high currents and resulting high temperatures. However, in the case of an internal short, e.g., if the positive tab comes lose and contacts the interior of the negative metal can, the separator could act as a fuse. That is, the impedance of the separator increases by two to three orders of magnitude due to an increase in cell temperature. 

One might note the striking similarity between Cases I and II. In both, a crucible failure allowed water to enter and mix with molten titanium. Steam (and hydrogen) formed and the pressure increased so as to bulge the crucible and rupture the safety discs. Tamping the water-metal mix by the fall of the electrode then caused a major explosion. No injuries resulted in the Case II incident because the vault walls provided protection. No data were available to allow an estimation of blast pressures, but as described, the vault construction maintained its integrity and the wave was forced to exit from the bottom. 

Accidents involving physical hazards can directly injure workers and can create additional hazards, for example, increased chemical exposure due to damaged protective equipment, or danger of explosion caused by the mixing of chemicals. Site personnel should constantly look out for potential safety hazards, and should immediately inform their supervisors of any new hazards so that proper action can be taken [1,21,31]. 

Azide is often used to introduce nitrogen by nucleophilic displacement on a halide or sulfonate. Care must be exercised when producing or handling azides, since they can be quite explosive. In fact, azides are rarely used on an industrial scale. Special facilities are required to work with most azides on scale. The safety factor improves as the carbon-to-nitrogen ratio in the substrate increases. Beyond being a source of nitrogen, they are most commonly used to protect the amine during carbohydrate synthesis. 

There have been two major accidents (Three Mile Island in the United States and Chernobyl in the former Soviet Union) in which control was lost in nuclear power plants, with subsequent rapid increases in fission rates that resulted in steam explosions and releases of radioactivity. The protective shield of reinforced concrete, which surrounded the Three Mile Island Reactor, prevented release of any radioactivity into the environment. In the Russian accident there had been no containment shield, and, when the steam explosion occurred, fission products plus uranium were released to the environment—in the immediate vicinity and then carried over the Northern Hemisphere, in particular over large areas of Eastern Europe. Much was learned from these accidents and the new generations of reactors are being built to be passive safe. In such passive reactors, when the power level increases toward an unsafe level, the reactor turns off automatically to prevent the high-energy release that would cause the explosive release of radioactivity. Such a design is assumed to remove a major factor of safety concern in reactor operation, see also Bohr, Niels Fermi, Enrico AIan-HATTAN Project Plutonium Radioactivity Uranium. 

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