Explosion hazards evacuation

Materials which (in themselves) are readily capable of detonation or of explosive decomposition or explosive reaction at normal temperatures and pressures. Includes materials which are sensitive to mechanical or loceilized thermal shock. If a chemical with this hazard rating is in an advanced or massive fire, the area should be evacuated. 

Employers, at a minimum, must have an emergency action plan that will facilitate the prompt evacuation of employees when there is an unwanted release of a highly hazardous chemical. This means that the employer s plan will be activated by an alarm system to alert employees when to evacuate, and that employees who are physically impaired will have the necessary support and assistance to get them to a safe zone. The intent of these requirements is to alert and move employees quickly to a safe zone. The use of process control centers or buildings as safe areas is discouraged. Recent catastrophes indicate that lives are lost in these structures because of their location and because they are not necessarily designed to withstand over-pressures from shock waves resulting from explosions in the process area. 

When primary fume capture is performed by the enclosure, furnace off-gas combustion efficiency is lower than experienced by furnace direct evacuation control. The off-gas, rich in carbon monoxide (CO), rises from furnace roof openings and partially burns and cools with enclosure air. Significant levels of CO have resulted in the enclosures and exhaust ducting from this type of combination. These levels are not explosive but present a potential hazard to personnel working in the enclosure or in downstream fume cleaning equipment. 

Do not approach the spill. It could be hazardous, or may produce an explosion, fire, or toxic fumes. Contact nearby persons advising Orem to tUso be cautious or to evacuate their residence if necessary. 

Dusts, particle sizes, 225 Dusts, hazard class, 521-523 Explosion characteristics, 524 Efficiency, centrifugal pumps, 200 Ejector control, 380 Ejector systems, 343, 344, 351 Air inleakage, table, 366, 367 Applications, 345 Calculations, 359-366 Chilled water refrigeration, 350 Comparison guide, 357, 375 Evacuation lime, 380, 381 Charts, 382 Example, 381 Features, 345... 

General Considerations 1 Location of people relative to the unit 2 Location of critical systems 3 Dominant wind direction 4 Climate and weather extremes earthquake, flooding, windstorms 5 Site topography 6 External hazards or threats (fire/explosion/toxic release from nearby process or facility aircraft subsidence sabotage) 7 Traffic flow patterns and clearances from process vessels and lines 8 Security and reliability of all critical feeds and utilities 9 Command center and alternate command center locations 10 Evacuation routes, emergency exits, safe rally spots... 

The liquid can be exploded by a detonator, though not by mechanical shock [1]. Use of propylene oxide as a biological sterilant is hazardous because of ready formation of explosive mixtures with air (2.8—37%). Commercially available mixtures with carbon dioxide, though non-explosive, may be asphyxiant and vesicant [1], Such mixtures may be ineffective, but neat propylene oxide vapour may be used safely, provided that it is removed by evacuation using a water-jet pump [2]. The main factors involved in the use and safe handling on a laboratory scale have been discussed [3]. The energy of decomposition (in range 340—500°C) has been measured as 1.114 kJ/g [4]. 

The response phase should use the American Medical Association s DISASTER algorithm. This stands for Detect, Incident Command, Scene Safety and Security, Assess Hazards, Support Required, Triage and TLeatment, Evacuation, and Recovery. An explosion is... 

ERA considers it a health hazard if a particular chemical gas has a ground-level concentration (GLC) greater than 1 x 10 g/m. An explosion in a chemical plant releases 1000 kg of this gas as a puff from ground level conditions. A residential community is located 4000 m downwind and 1000 m crosswind Ifom the source of the explosion. If the wind speed is 6 m/s and the stability category is unstable, how much time do the residents have to evacuate the town ... 

Distances recommended in the NAERG were developed to assist responders at the scene of traditional hazardous materials incidents. It is important to realize that these distances were not developed to account for additional dispersal from an explosive device or from a spray release. In these cases, the initial isolation and downwind evacuation distances should begin at the edge of any liquid or solid contaminahon caused by the dispersal device. Figure 3.2 illustrates an irregular release downwind hazard assessment. 

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