And dust explosions

Health and Safety Factors. Both pyromellitic acid and its dianhydride irritate skin, eyes, and mucous membranes, and they cause skin sensitization (156). When it comes in contact with moist tissue the dianhydride converts to the acid. Direct contact with should be avoided and protective clothing should be worn in areas where it is used. The LD q for intergastric administration in rats is 2.2—2.6 g/kg (157). In 6-mo experiments, the maximum nontoxic dose was 0.07 mg/kg/d, and it affected the fiver, kidney, and reproductive tract. Precautions against fire and dust explosions as explained in the terephthafic acid section should be foUowed. 

Frevention of Fire and Dust Explosions in the Chemical, Dje, Fharmaceutical, andFlastics Industrj, NFFM 654, National Fire Protection Association, Quiucy, Me., 1982. 

NFPA 654 Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids, 1997 edition. 

Lunn, G.A. (1984) Venting Gas and Dust Explosions - A Review, Instn of Chem. Eng., London. 

KjMdman, L., and R. Huhtanen. 1986. Numerical simulation of vapour cloud and dust explosions. Numerical Simulation of Eluid Elow and Heat/Mass Transfer Processes. Vol. 18, Lecture Notes in Engineering, 148-158. 

Other references include CCPS Guidelines for Engineering Design for Process Safety (Ref. 78) NFPA 68 Venting of Deflagrations (Ref. 79) NFPA 69 Explosion Prevention Systems (Ref. 80) NFPA 654 Prevention of Fire and Dust Explosions in the Chemical Dye, Pharmaceutical, and Plastics Industries (Ref. 81) and VDI 3673 Pressure Release of Dust Explosions (Ref. 82). 

The explosion characteristics determined using the vapor and dust explosion apparatus are used in the following way ... 

Additional hazards in plant operations include specific gas and dust explosions, but such considerations are outside the scope of this book. Reference can be made to another CCPS Guidelines book [159] for issues relative to certain explosions. 

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