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Reduce the risks for sulfur fires and explosions with the expanded edition of NFPA 655: Standard for Prevention of Sulfur Fires and Explosions.

Use the essential steps and requirements outlined in the 2012 NFPA 655 to eliminate or reduce hazards encountered in the crushing, grinding, and pulverizing of bulk and liquid sulfur. NFPA 655 also prescribes the safe handling of all forms of sulfur, including ground sulfur and molten sulfur.

This edition introduces an alternative means for determining where in a facility a combustible dust hazardous condition exists. It also clarifies how to choose between prescriptive or performance-based options when applying NFPA 655.

Other changes help you understand and correctly address hazards.

• Clarification of the dust layer depth criterion for determining whether a combustible dust hazardous condition exists
• New housekeeping requirements addressing the hierarchy of cleaning methods and the frequency of housekeeping based upon rate of accumulation of combustible dusts
• Added requirements for employee training; and new rules applicable to contractors and subcontractors
• Added PPE for flash fires, selected according to NFPA 2113: Standard on Selection, Care, Use, and Maintenance of Flame-Resistant Garments for Protection of Industrial Personnel Against Flash Fire
• Annex B illustrating how to apply the methods for determining existence of combustible dust hazardous condition
• Added Annex text explaining protection strategies against static electrical ignition concerns where intermediate bulk containers (IBC) are used for sulfur storage and transport