Tham khảo tài liệu 'industrial ventilation episode 6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | UFC 3-410-04N 25 October 2004 CHAPTER 6 ABRASIVE BLASTING FACILITIES 6-1 FUNCTION. Workers prepare the surface of aircraft shipboard mechanical utility and other equipment in abrasive blasting facilities for surface coating welding and other operations. This Chapter does not apply to temporary blasting enclosures. 6-2 OPERATIONAL CONSIDERATIONS. Silica sand is prohibited from use in fixed location enclosures. Avoid using agricultural media . peach pits rice hulls walnut shells . They are particularly susceptible to explosions. 6-3 DESIGN CRITERIA. Apply the general technical requirements of Chapter 2 and the specific requirements of this Chapter to ensure the proper function operation and maintenance of an abrasive blasting facility. Use this information when assembling a specification package for an enclosure manufacturer or inspecting an enclosure already in place. Exhaust Air. Determine the type of dust hazard and the minimum average air velocity through the blasting enclosure in accordance with 29 CFR a Abrasive Blasting ANSI Abrasive Blasting - Ventilation Safe Practices for Fixed Location Enclosures sections 4 5 6 and A7 NFPA 68 Standard for the Processing and Finishing of Aluminum NFPA 69 Standard on Explosion Prevention NFPA 70 NFPA 91 and NFPA 654. Refer to NFPA 65 NFPA 480 Storage Handling and Processing of Magnesium NFPA 481 Storage Handling and Processing of Titanium NFPA 482 Storage Handling and Processing of Zinc and NFPA 485 Storage Handling and Processing of Lithium when blasting on materials containing aluminum magnesium titanium zirconium and lithium respectively. Blasting Cabinets. Install baffles around air inlets to prevent abrasive material from escaping from the cabinet. Use a minimum inward air velocity of m s 500 fpm at all operating openings. Discharge the exhaust air outside the building. Walk-in Blasting Enclosures. Design the enclosure so that the air flows from either the ceiling to the floor .
