2020 NFPA 55 Code - Current Edition
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  • Description

    NFPA 55, 2020 edition, is a must-have resource for improved industrial safety around compressed gases and cryogenic fluids.

    Working with and around industrial gas calls for a specialized skill set and understanding of general operating and safety requirements. NFPA 55, Compressed Gases and Cryogenic Fluids Code, demonstrates how to mitigate physiological, over-pressurization, explosion, and flammability hazards relating to these highly combustible materials in all types of occupancies.

    This NFPA publication is essential for everyone from installers, contractors, and engineers to code enforcers, inspectors, and environmental health and safety personnel. NFPA 55 provides comprehensive coverage of the fundamentals for safer and more effective installation, storage, use, and handling of gases in portable and stationary containers, cylinders, equipment, and tanks.

    Code content covers:

    • General requirements for emergency readiness and response
    • Classification of hazardous materials
    • Building control areas and fire and hazard protection systems
    • Storage, use, and handling of compressed gases and cryogenic fluids
    • Bulk oxygen, gas hydrogen, bulk liquefied hydrogen, gas generation, and carbon dioxide systems
    • Storage, handling, and use of ethylene oxide for sterilization and fumigation
    • General requirements and special considerations for acetylene cylinder charging plants
    • Provisions and maintenance procedures for liquid nitrous oxide systems
    • Health care facilities cryogenic fluid central supply systems

    Be confident you have the most current information you need to stay code-compliant and help safeguard lives and property.

    NFPA 55 has been significantly revised to reflect the latest industry practices, trends, and technologies. The 2020 edition offers the most complete set of industrial gas requirements. Changes include:

    • A new definition in Chapter 3 for press-connect fittings. The definition incorporates fitting designs with and without elastomeric seals
    • A code change in Chapter 6, Table 6.6, involving pyrophoric gases to provide a safe system for control of these types of gases in high hazard gas rooms serving Protection Level 5 fabrication facilities
    • A new subsection in Chapter 8 under Pressure Relief Devices requiring pressure relief devices involved with cryogenic fluid piping systems venting to the outdoors when the maximum allowable working pressure or maximum process operating pressure is released
    • New text added to Section 11.3, Location of Bulk Liquefied Hydrogen Systems, to reflect the intentional omission of vent stacks in hydrogen storage systems as they relate to setback distances
    • New text in Liquid Nitrous Oxide Systems in Chapter 16 directing the reader to Chapter 17 for medical gas applications

    Help protect your personnel and facility from compressed gas and cryogenic fluid hazards.

    NFPA 55 helps improve safety in settings that use, produce, or distribute compressed gases or cryogenic fluids. Get your copy of NFPA 55, Compressed Gases and Cryogenic Fluids Code, by placing your order today.


    Are you interested in other editions of NFPA 55? Use the drop-down menu above to select the edition year you need.

  • Table of Contents (2020 Current Edition)

    NFPA® 55 Compressed Gases and Cryogenic Fluids Code, 2020 Edition

    Chapter 1 Administration
    1.1 Scope.
    1.2 Purpose.
    1.3 Application.
    1.4 Retroactivity.
    1.5 Equivalency.
    1.6 Units and Formulas.
    1.7 Enforcement.
    Chapter 2 Referenced Publications
    2.1 General.
    2.2 NFPA Publications.
    2.3 Other Publications.
    2.4 References for Extracts in Mandatory Sections.
    Chapter 3 Definitions
    3.1 General.
    3.2 NFPA Official Definitions.
    3.3 General Definitions.
    Chapter 4 General Requirements
    4.1 Permits.
    4.2 Emergency Plan.
    4.3 Facility Closure.
    4.4 Out-of-Service Stationary Bulk Gas Systems.
    4.5 Management Plan and Hazardous Materials Documentation.
    4.6 Release of Hazardous Materials.
    4.7 Personnel Training.
    4.8 Emergency Response Liaison.
    4.9 Ignition Source Controls.
    4.10 Signs.
    4.11 Protection from Vehicular Damage.
    4.12 Building Construction Materials.
    Chapter 5 Classification of Hazards
    5.1 Hazardous Materials Classification.
    Chapter 6 Building-Related Controls
    6.1 General.
    6.2 Control Areas.
    6.3 Occupancy Protection Levels.
    6.4 Gas Rooms.
    6.5 Hydrogen Gas Rooms.
    6.6 Detached Buildings.
    6.7 Weather Protection.
    6.8 Electrical Equipment.
    6.9 Employee Alarm System.
    6.10 Explosion Control.
    6.11 Fire Protection Systems.
    6.12 Lighting.
    6.13 Hazard Identification Signs.
    6.14 Spill Control, Drainage, and Secondary Containment.
    6.15 Shelving.
    6.16 Vent Pipe Termination.
    6.17 Ventilation.
    6.18 Gas Cabinets.
    6.19 Exhausted Enclosures.
    6.20 Source Valve.
    Chapter 7 Compressed Gases
    7.1 General.
    7.2 Storage.
    7.3 Use and Handling.
    7.4 Medical Gas Systems.
    7.5 Corrosive Gases.
    7.6 Flammable Gases.
    7.7 Oxidizing Gases.
    7.8 Pyrophoric Gases.
    7.9 Toxic and Highly Toxic Gases.
    7.10 Unstable Reactive Gases (Nondetonable).
    Chapter 8 Cryogenic Fluids
    8.1 General.
    8.2 Containers — Design, Construction, and Maintenance.
    8.3 Pressure Relief Vent Piping.
    8.4 Marking.
    8.5 Security.
    8.6 Separation from Hazardous Conditions.
    8.7 Electrical Wiring and Equipment.
    8.8 Service and Repair.
    8.9 Unauthorized Use.
    8.10 Leaks, Damage, and Corrosion.
    8.11 Lighting.
    8.12 Storage.
    8.13 Use and Handling.
    Chapter 9 Bulk Oxygen Systems
    9.1 General.
    9.2 Materials of Construction.
    9.3 Location of Bulk Oxygen Systems.
    9.4 System Fabrication.
    9.5 Inspection.
    Chapter 10 Gas Hydrogen Systems
    10.1 Applicability.
    10.2 General.
    10.3 Hydrogen Systems Having Quantities Greater Than the MAQ.
    10.4 Bulk Gaseous Hydrogen System.
    Chapter 11 Bulk Liquefied Hydrogen Systems
    11.1 General.
    11.2 Design of Bulk Liquefied Hydrogen Systems.
    11.3 Location of Bulk Liquefied Hydrogen Systems.
    11.4 Design Considerations at Specific Locations.
    11.5 Cargo Transport Unloading.
    Chapter 12 Gas Generation Systems
    12.1 General.
    12.2 Corrosive Gases. (Reserved)
    12.3 Flammable Gases — Cryogenic. (Reserved)
    12.4 Oxidizing Gases. (Reserved)
    12.5 Other Gases. (Reserved)
    12.6 Pyrophoric Gases. (Reserved)
    12.7 Toxic and Highly Toxic Gases. (Reserved)
    12.8 Unstable Reactive Gases. (Reserved)
    Chapter 13 Carbon Dioxide Systems
    13.1 General.
    13.2 Uninsulated Carbon Dioxide Compressed Gas Systems. (Reserved)
    13.3 Insulated Carbon Dioxide Compressed Gas Systems.
    13.4 Insulated Liquid Carbon Dioxide Systems.
    13.5 Materials of Construction.
    13.6 Operating Instructions.
    13.7 Small Insulated Liquid Carbon Dioxide Indoor Systems.
    13.8 Small Insulated Liquid Carbon Dioxide Outdoor Systems.
    13.9 Large Indoor Insulated Liquid Carbon Dioxide Systems. (Reserved)
    13.10 Large Outdoor Insulated Liquid Carbon Dioxide Systems.
    13.11 Carbon Dioxide Beverage Systems.
    Chapter 14 Storage, Handling, and Use of Ethylene Oxide for Sterilization and Fumigation
    14.1 General.
    14.2 Receiving and Unloading Ethylene Oxide Containers.
    14.3 Storage of Ethylene Oxide.
    14.4 Piping Systems.
    14.5 Gas Dispensing Areas.
    14.6 Operations.
    14.7 Electrical Installation.
    14.8 Sterilizer Construction.
    14.9 Disposal and Emissions.
    14.10 Maintenance.
    14.11 Construction.
    14.12 Fire Protection.
    Chapter 15 Acetylene Cylinder Charging Plants
    15.1 General.
    15.2 Location.
    15.3 Building-Related Controls.
    15.4 Design, Installation, and Testing.
    15.5 Process Operations.
    15.6 Maintenance. (Reserved)
    15.7 Special Problems — Raw Materials.
    Chapter 16 Liquid Nitrous Oxide Systems
    16.1 General.
    16.2 Location of Bulk Nitrous Oxide Systems.
    16.3 Container Design.
    16.4 Container Installation.
    16.5 Materials of Construction.
    16.6 Vaporizers and Heaters.
    16.7 Pumps.
    16.8 Strainers and Filters.
    16.9 Flow Meters.
    16.10 Cleaning.
    16.11 Maintenance Procedures.
    16.12 Small Insulated Liquid Nitrous Oxide Indoor Systems. (Reserved)
    Chapter 17 Cryogenic Fluid Central Supply Systems for Health Care Facilities
    17.1 General.
    17.2 Cryogenic Fluid Central Supply Systems Installation.
    17.3 Cryogenic Fluid Central Supply Systems Operation.
    17.4 Main Supply System.
    17.5 Reserve Supply System.
    17.6 Cryogenic Fill System.
    17.7 Vaporizers.
    17.8 High-Pressure Manifolds.
    17.9 Pressure Control Devices.
    17.10 Pressure Relief Devices.
    17.11 Tubing and Valves.
    17.12 Alarms.
    Annex A Explanatory Material
    Annex B Attended Operations
    Annex C Physical Properties of Hydrogen
    Annex D Significant Properties of Ethylene Oxide
    Annex E Explanation of Methodology Utilized to Develop Separation Distances
    Annex F Sample Ordinance Adopting NFPA 55
    Annex G OSHA Requirements for Hydrogen Systems
    Annex H Determination of Separation Distances for Bulk Gaseous Hydrogen Systems
    Annex I Informational References
  • Prior Editions

    The 2016 edition of NFPA 55 helps users ensure industrial safety around compressed gases and cryogenic fluids.

    Compressed gases and cryogenic fluids require special safety measures that offer protection from physiological, over-pressurization, explosive, and flammability hazards. NFPA 55, Compressed Gases and Cryogenic Fluids Code fills the safety gap with the most comprehensive set of industrial gas requirements in the National Fire Codes.

    Depend on the 2016 edition of NFPA 55 for the latest fundamental requirements essential for safe installation, storage, use, and handling of gases in portable and stationary containers, cylinders, equipment, and tanks in all occupancy types.

    Major changes respond to industry needs and help you work more confidently:

    • Complete reorganization of hydrogen requirements works to clarify requirements by system size.
    • New chapter addresses the safe storage and use of liquid nitrous oxide.
    • Changes to CO2 system requirements expand requirements for beverage systems.

    NFPA 55 is essential for installers, contractors, engineers, facility managers, and anyone responsible for safety in settings that use, produce, or distribute compressed gases or cryogenic fluids. It's also a must-have resource for code enforcers, inspectors, and environmental health and safety (EHS) personnel. (Softbound, 143 pp., 2016)


    Interested in other editions of NFPA 55? Use the drop down menu above to select the edition year you need.

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    • A code or standard is a framework—a set of rules to follow with a goal to achieve a certain result
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    The simplest way to think about it is that codes and standards list the technical requirements while handbooks explain those requirements to clarify how to apply them.

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