Follow the 2010 NFPA 91 to prevent exhaust systems from spreading fire and increasing explosion risks.
NFPA 91: Standard for Exhaust Systems for Air Conveying of Vapors, Gases, Mists, and Noncombustible Particulate Solids provides minimum requirements for the design, construction, installation, operation, testing, and maintenance of these systems except as modified or amplified by other applicable NFPA® standards.
Key changes in the 2010 Standard include:
- Updated definitions for consistency with other particulate solids documents, such as NFPA 654: Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particular Solids
- Amended scope and application clarify that the provisions are intended to provide protection against fire and explosion hazards.
- Revised requirements pertaining to access to ducts for purposes of inspection provide a more performance oriented approach.
- New chapter on air-material separators based on provisions in NFPA 654
- Modified testing and maintenance rules require that provisions be applicable retroactively. This is consistent with the other particulate solids documents, such as NFPA 654.
- Revised requirements for duct clearances from combustible construction include more comprehensive criteria for various installations of duct systems.
The 2010 NFPA 91 is essential for process industries in which there is production or release of gases, vapors, or solids that are pneumatically conveyed through duct systems; design engineers; fire protection engineers; safety and health professionals; industrial hygienists; and fire and building officials. (Softbound, 18 pp., 2010)
NFPA® 91 Standard for Exhaust Systems for Air Conveying of Vapors, Gases, Mists, and Noncombustible Particulate Solids 2010 Edition
Chapter 1 Administration
Chapter 2 Referenced Publications
2.2 NFPA Publications
2.3 Other Publications
2.4 References for Extracts in Mandatory Sections
Chapter 3 Definitions
3.2 NFPA Official Definitions
3.3 General Definitions
Chapter 4 Design and Construction
4.1 General Requirements
4.2 Duct Material and Construction
4.4 Design Requirements
4.5 Hangers and Supports
4.6 Duct Installation
Chapter 5 Corrosive Materials
Chapter 6 Air-Moving Devices
6.2 Flammable or Combustible Materials
6.5 Maintenance and Inspection
6.7 Flexible Connections
Chapter 7 Air-Material Separators (Air Separation Devices)
7.1 General Requirements
7.2 Separators for Noncombustible Particulates
7.3 Separators for Flammable Gases, Vapors, and Mists
Chapter 8 Ignition Sources
8.1 Electrical Equipment
8.2 Static Electricity
8.4 Open Flames and Sparks
8.5 Removal of Ferrous Materials
8.6 Belt Drives
Chapter 9 Fire Protection
9.3 Testing and Inspection
Chapter 10 Testing and Maintenance
10.3 System Test
10.4 System Inspection.
10.6 Maintenance Program
10.7 Maintenance Log
Annex A Explanatory Material
Annex B Informational References