1 Del. Admin. Code § 705-1-12.0

Current through Register Vol. 28, No. 4, October 1, 2024

Section 705-1-12.0 - Dusts

12.1 Applicability.

12.1.1 This section shall be applicable only to those operations or occupancies involving combustible dusts which are not otherwise regulated by an applicable NFPA code or standard as adopted and/or modified by these Regulations.

12.2 General Requirements.

12.2.1 The accumulation of dust in quantities sufficient to create a fire or explosion hazard on electric motors, walls, ledges, or other interior surfaces, or on the roof of any building on which dust may settle is prohibited. Metallic dust shall be stored in tightly covered metal containers in a cool, dry place.

12.2.2 Every plant, factory, workshop, or other premises in which dust is produced as a product or as a result of operations in the production of other products in such quantities as to create a possible fire or explosion hazard, shall be equipped and maintained with an approved pneumatic or mechanical dust collection system designed, maintained, and operated in accordance with applicable NFPA codes and standards as adopted and/or modified by these Regulations.

Exception: This section shall not apply to storage bins equipped with explosion vents of sufficient area to relieve any explosion to the outside atmosphere.

12.2.3 All dust-producing or dust-agitation machinery, such as grinding mills and separators, and all elevators, elevator legs, spouts, hoppers, and other conveyors shall be provided with casings or enclosures maintained as nearly dust-tight as possible.

12.2.4 Approved magnetic or pneumatic separators shall be installed ahead of all shellers, crackers, crushers, grinding machines, pulverizers, and similar machines in which the entrance of foreign materials may cause sparks to be generated.

12.2.5 All machinery and metal parts of the crushing, drying, pulverizing, and conveying systems shall be electrically grounded.

12.3 Explosion Prevention and Suppression.

12.3.1 Dust explosion hazards shall be minimized by use of appropriate control measures as set forth in the applicable NFPA codes and standards as adopted and/or modified by these Regulations. The Standard on Explosion Prevention Systems, NFPA 69, and Guide for Venting of Deflagrations, NFPA 68, may be used to meet the requirements of this paragraph with due regard to the precautionary measures contained in these publications.

12.4 Sources of Ignition.

12.4.1 Smoking and Open Flames. Smoking and the carrying of matches, the use of heating, or other devices employing an open flame, or the use of any spark-producing equipment is prohibited in areas containing dust-producing, and/or dust-agitation operations.

12.4.2 Electrical Power and Lighting. Artificial lighting in areas containing dust-producing or dust-agitation operations shall be by electricity. All electrical wiring and equipment in such areas shall be installed in accordance with the provisions of the National Electrical Code, NFPA 70, for Class II Hazardous Locations. The State Fire Marshal shall be responsible for designating the areas requiring hazardous location electrical classification and shall classify the area in accordance with the classification system set forth in the National Electrical Code, NFPA 70, as adopted and/or modified by these Regulations.

12.4.3 Portable Fire Extinguishers Required. Portable fire extinguishers shall be installed for extra hazard occupancy protection.

1 Del. Admin. Code § 705-1-12.0