1、 Errata NFPA 61 Standard for the Prevention of Fires and Dust Explosions in Agricultural and Food Processing Facilities 2017 Edition Reference: A.8.7.2.1, A.8.7.2.2, A.8.7.2.4 and A.9.10.1(7) Errata No: 61-17-1 The Technical Committee on Agricultural Dusts and the Correlating Committee on Combustibl
2、e Dusts notes the following error in the 2017 edition of NFPA 61, Standard for the Prevention of Fires and Dust Explosions in Agricultural and Food Processing Facilities. 1. Add Annex material that was omitted in the printing of NFPA 61 to read as follows: A.8.7.2.1 Techniques to prevent or reduce d
3、ust generation and dispersal are vital to any dust control program. These techniques include the use of reduced handling speeds, dead boxes, choked feeding, snorkel loaders, dusttight enclosures, short vertical runs, cleaning, and dust suppressant, as well as many others. Preventive dust control is
4、encouraged, since it can effectively reduce total dust control costs as well as the demands placed on the performance of subsequent dust control techniques outlined in Section 8.4 and 8.7.2. Various oils and other liquids have been used as a dust suppressant. Each dust suppressant has its limitation
5、s and should be used with regard to applicable grain and food standards and regulations. Oil dust suppressants should not be applied directly into the leg, as there have been cases of belt slippage using oil. Application should be made in the transition spout between the receiving pit and the receiv
6、ing leg. If this is not feasible, application can be made at a transfer point or discharge of a conveying system, or directly on a conveyor belt or into a screw auger. The idea is to apply the dust suppressant where there is grain turbulence, thereby allowing the dust suppressant to mix thoroughly.
7、A.8.7.2.2 Legs are the most frequent location of known primary dust explosions and can experience malfunctions, which can result in ignition of the returned dust. This section is not intended to apply to point-of-use dust collectors. A.8.7.2.4 The purpose of this dust control method is to remove dis
8、placed air from the equipment so that it operates under a slightly negative pressure in order to reduce fugitive dust emissions from the equipment, keep the dust generated from the material being conveyed with the material, and eliminate the propagation hazard of interconnecting the conveying equipm
9、ent with a central dust collection system. The dust is not removed from the equipment, and this approach does not lower the risk of a dust deflagration within the equipment itself. The point-of-use dust collector should be located near the material inlet point on the conveyor. Little dust should be
10、drawn into the point-of-use collector. When used on a bucket elevator leg, it is recommended that the point-of-use dust collector be installed in the down leg of the bucket elevator leg to facilitate dust release from the filters. The cross-sectional area of the transition between the duct and the l
11、eg casing should be 2.5 times the cross-sectional area of the dust collector inlet. The angle of the transition duct to the leg casing should be no less than 60 degrees. This dust control method should be used in conjunction with a good housekeeping program, equipment maintenance strategy, and dust
12、deflagration mitigation actions as required. A.9.10.1(7) Contractor records typically include information such as the contract documentation with scope of work and necessary insurance coverage, the contractors safety programs, records demonstrating the contractors safety performance, qualifications
13、and certifications necessary for the work to be done, periodic evaluations of the contractors work performance, and records demonstrating that the employees of the contractor have been trained to safely perform the assigned work. 652:A.9.10.1(8) Issue Date: September 14, 2016 (Note: Electronic products and pamphlet reprints may have this errata incorporated. For current information about the NFPA Codes and Standards, including this errata, please see www.nfpa.org/docinfo) Copyright 2016 All Rights Reserved NATIONAL FIRE PROTECTION ASSOCIATION
