NFPA 54/ANSI Z223.1, National Fuel Gas Code

2021 Edition

Improve public safety by referencing NFPA 54/ANSI Z223.1, 2021 edition, for the latest criteria for the acceptable use of gas in homes and buildings.

From carbon monoxide poisoning to the risks of fire and explosion, there are many hazards inherent with the utilization of gaseous fuels. NFPA 54 offers comprehensive provisions for the safe design, installation, operation, maintenance, purging, and inspection of gas piping, equipment, accessories, and appliances supplied with fuel gas.

The code covers:

• Piping system design, materials, and components
• Pipe sizing and installing pipes underground, aboveground, and inside concealed spaces
• Piping inspection, testing, system leak check, and purging
• Requirements for process air and installation of appliances
• Minimum safe performance criteria, general requirements, and specifications for venting combustion products.

Take confidence you are up to date with the latest information on fuel gas installations by referencing the new NFPA 54.

The National Fuel Gas Code is the cumulative result of the vast knowledge of a broad range of stakeholders and organizations with expertise in gas piping and equipment and the use of gaseous fuels. An industry-accepted standard, the recently amended NFPA 54 features significant changes and additions to account for state-of-the-art equipment, practices, materials, trends, and technology.

Changes to the 2021 edition include:

• Revisions in Chapter 10 requiring appliances to be listed to and in compliance with the appropriate ANSI/CSA appliance listing standard
• Addition of a table for through the wall vent terminal clearances to Chapter 12, along with an associated annex figure that coordinates this code with the clearances in ANSI product standards
• Definition of engineering methods in Chapter 4 to provide guidance to authorities having jurisdiction on acceptable methods, eliminating the need to approve all engineering methods used individually
• Revised and reorganized electric isolation requirements for gas piping installation to better reflect where the dielectric union is to be installed in the system and what it is protecting

Make sure you have the most current provisions to help ensure fuel gas safety on consumer premises.

Help protect lives and property from fuel gas dangers by purchasing your copy of NFPA 54/ANSI Z223.1, National Fuel Gas Code, 2021 edition.

2018 Edition

Ensure a safe fuel gas installation using the 2018 edition of NFPA 54/ANSI Z223.1, National Fuel Gas Code.

NFPA 54, National Fuel Gas Code provides industry-accepted guidance for the safe installation and operation of fuel gas piping systems, appliances, equipment, and accessories. The 2018 edition includes updates based on recognized risks, recent research, and the techniques, materials, developments, and construction practices in use today. From design to installation, maintenance, and inspection -- no matter what aspect of fuel gas safety your job involves, the latest edition of the National Fuel Gas Code is essential.

Update to the 2018 edition of the NFPA 54 for greater confidence in CSST bonding.

Be sure you're working with the most up-to-date information on the National Fuel Gas Code's bonding requirement for corrugated stainless steel tubing (CSST). All CSST used for fuel gas piping must be bonded to the building grounding system to prevent damage to the system due to nearby lightning strikes. In the 2018 edition, revisions to piping requirements include allowing listed arc-resistant jacket or coated CSST to use the appliance's electrical grounding connector as the bonding means and recognizing stainless steel smooth wall pipe and tubing products as acceptable piping materials.

Other changes impact contractors, installers, and code officials:

• The minimum allowed wall thickness of carbon and stainless steel pipe is revised to Schedule 10, however joints on Schedule 10 pipe cannot be made with screwed fittings.
• Press-connect fittings are now an acceptable joining method for pipe.
• Revisions to the venting requirements include requiring listing to the appropriate UL standards for plastic venting materials, factory-built chimneys, Type B and BW vents, chimney lining systems, and special gas vents.
• Direct vent clearances to building openings for appliances with an input above 150,000 Btu (44 kW) are to be in accordance with the appliance manufacturer's installation instructions.
• An existing gas appliance installation is required to be inspected for combustion air and venting code compliance when the building structure that it is installed in is modified with specific air infiltration-reducing changes.

Annexes provide a wealth of additional information such as:

• Details on coordinating appliance and equipment design, construction, and maintenance -- including a design and construction checklist
• Steps on checking for leakage and suggested emergency procedures for gas leaks

Never underestimate fuel gas dangers!

The NFPA 54/ANSI Z223.1, National Fuel Gas Code provides the most effective means of ensuring fuel gas safety on consumers' premises. Update now for the latest pipe sizing tables; design requirements; installation provisions; inspection, testing, and purging requirements; and venting system rules that address fuel gas risks. (Print, 168 pp., 2018)

2015 Edition

NFPA 54: National Fuel Gas Code provides the most effective means of ensuring fuel gas safety on consumers' premises.

NFPA 54: National Fuel Gas Code provides critical guidance for the safe installation and operation of fuel gas piping systems, appliances, equipment, and accessories. Installers, designers, AHJs, maintainers, inspectors, and facility managers look to the Code for design requirements; inspection, testing, and purging requirements; pipe sizing tables; and venting system rules that address fuel gas risks. Each edition builds on the next, through consensus-based changes that reflect the evolving needs of the field and the latest information about fuel gas safety.

The 2015 NFPA 54: National Fuel Gas Code includes updates based on recognized risks, recent research, and the techniques, materials, developments, and construction practices in use today. From design to installation, maintenance, and inspection.

2012 Edition

The 2012 NFPA 54 incorporates indoor gas piping purging rules that address recommendations by the U.S. Chemical Safety Board (CSB). In response to a devastating gas piping purging accident, NFPA 54 received an emergency Tentative Interim Amendment to the purging requirements in the 2009 Code. With minor editorial changes, the 2012 NFPA 54 presents these new rules specifying mandatory use of combustible gas indicators and detectors so employers can identify the presence of fuel gas. Other major changes improve safety and facilitate Code application; such as a new bonding clamp location for Corrugated Stainless Steel Tubing (CSST) gas piping that clarifies bonding requirements added in the 2009 edition.

2009 and 2006 Editions -

The 2009 NFPA 54: National Fuel Gas Code reflects scores of proposals from the field. A new bonding requirement for Corrugated Stainless Steel Tubing (CSST) gas piping installed inside buildings helps protect against threats likely to energize gas piping. This edition also addresses a new system of connecting copper tubing using a crimping tool for press-connect fittings, and includes a new rule for a dedicated master shutoff valve for laboratories. Revised requirements for connectors to radiant tube heaters help prevent cracks, leaks, or fractures. Additional requirements for commercial cooking appliance connectors reduce the risk of fugitive gas, potential fires, and subsequent losses.

The 2006 NFPA 54: National Fuel Gas Code includes revised data that helps designers and engineers properly size longer installations; dozens of pipe sizing tables have been extended with information for all piping up to 2,000 feet. A first-time requirement addresses support of rooftop piping to protect against wind damage. Revised requirements for appliance shutoff valves allow manifold systems with all shutoff valves in one location up to 50 feet from the most remote appliance. Definitions are organized by categories, and chapters dealing with piping, installation, and venting are grouped together for ease of use.

NFPA^® 54 ANSI Z223.1–2021 National Fuel Gas Code, 2021 Edition

Chapter 1 Administration

1.1 Scope.
1.2 Purpose.
1.3 Retroactivity.
1.4 Equivalency.
1.5 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

4.1 Qualified Agency.
4.2 Interruption of Service.
4.3 Prevention of Accidental Ignition.
4.4 Noncombustible Material. 
4.5 Engineering Methods.

Chapter 5 Gas Piping System Design, Materials, and Components

5.1 Piping Plan.
5.2 Interconnections Between Gas Piping Systems.
5.3 Sizing of Gas Piping Systems.
5.4 Operating Pressure.
5.5 Piping Materials and Joining Methods.
5.6 Gas Meters.
5.7 Gas Pressure Regulators.
5.8 Overpressure Protection Devices.
5.9 Back Pressure Protection.
5.10 Low-Pressure Protection.
5.11 Shutoff Valves.
5.12 Excess Flow Valve(s).
5.13 Expansion and Flexibility.
5.14 Pressure Regulator and Pressure Control Venting.

Chapter 6 Pipe Sizing

6.1 Pipe Sizing Methods.
6.2 Sizing Natural Gas Piping Systems.
6.3 Sizing Propane Piping Systems.
6.4 Sizing Equations.

Chapter 7 Gas Piping Installation

7.1 Installation of Underground Piping.
7.2 Installation of Aboveground Piping.
7.3 Concealed Piping in Buildings.
7.4 Piping in Vertical Chases.
7.5 Gas Pipe Turns.
7.6 Drips and Sediment Traps.
7.7 Outlets.
7.8 Manual Gas Shutoff Valves.
7.9 Prohibited Devices.
7.10 Systems Containing Gas–Air Mixtures Outside the Flammable Range.
7.11 Systems Containing Flammable Gas–Air Mixtures.
7.12 Electrical Bonding and Grounding.
7.13 Electrical Circuits.
7.14 Electrical Connections.

Chapter 8 Inspection, Testing, and Purging

8.1 Pressure Testing and Inspection.
8.2 Piping System Leak Check.
8.3 Purging Requirements.

Chapter 9 Appliance, Equipment, and Accessory Installation

9.1 General.
9.2 Accessibility and Clearance.
9.3 Air for Combustion and Ventilation.
9.4 Appliances on Roofs.
9.5 Appliances in Attics.
9.6 Appliance and Equipment Connections to Building Piping.
9.7 Electrical.
9.8 Room Temperature Thermostats.

Chapter 10 Installation of Specific Appliances

10.1 General.
10.2 Air-Conditioning Appliances.
10.3 Central Heating Boilers and Furnaces.
10.4 Clothes Dryers.
10.5 Conversion Burners.
10.6 Decorative Appliances for Installation in Vented Fireplaces.
10.7 Gas Fireplaces, Vented.
10.8 Direct Gas-Fired Heating and Forced Ventilation Appliances.
10.9 Duct Furnaces.
10.10 Floor Furnaces.
10.11 Food Service Appliance, Floor-Mounted.
10.12 Food Service Appliances, Counter Appliances.
10.13 Household Cooking Appliances.
10.14 Illuminating Appliances.
10.15 Incinerators, Commercial-Industrial.
10.16 Infrared Heaters.
10.17 Open-Top Broiler Units.
10.18 Outdoor Cooking Appliances.
10.19 Pool Heaters.
10.20 Refrigerators.
10.21 Room Heaters.
10.22 Stationary Gas Engines.
10.23 Gas-Fired Toilets.
10.24 Unit Heaters.
10.25 Wall Furnaces.
10.26 Water Heaters.
10.27 Compressed Natural Gas (CNG) Vehicular Fuel Systems.
10.28 Appliances for Installation in Manufactured Housing.
10.29 Fuel Cell Power Plants.
10.30 Outdoor Open Flame Decorative Appliances.
10.31 Outdoor Infrared Heaters.

Chapter 11 Procedures to Be Followed to Place Appliance in Operation

11.1 Adjusting the Burner Input.
11.2 Primary Air Adjustment.
11.3 Safety Shutoff Devices.
11.4 Automatic Ignition.
11.5 Protective Devices.
11.6 Checking the Draft.
11.7 Operating Instructions.

Chapter 12 Venting of Appliances

12.1 Minimum Safe Performance.
12.2 General.
12.3 Specification for Venting.
12.4 Design and Construction.
12.5 Type of Venting System to Be Used.
12.6 Masonry, Metal, and Factory-Built Chimneys.
12.7 Gas Vents.
12.8 Single-Wall Metal Pipe.
12.9 Through-the-Wall Vent Termination.
12.10 Condensation Drain.
12.11 Vent Connectors for Category I Appliances.
12.12 Vent Connectors for Category II, Category III, and Category IV Appliances.
12.13 Draft Hoods and Draft Controls.
12.14 Manually Operated Dampers.
12.15 Automatically Operated Vent Dampers.
12.16 Obstructions.

Chapter 13 Sizing of Category I Venting Systems

13.1 Additional Requirements to Single Appliance Vent.
13.2 Additional Requirements to Multiple-Appliance Vent.

Annex A Explanatory Material
Annex B Sizing and Capacities of Gas Piping
Annex C Suggested Method of Checking for Leakage
Annex D Suggested Emergency Procedure for Gas Leaks
Annex E Flow of Gas Through Fixed Orifices
Annex F Sizing of Venting Systems Serving Appliances Equipped with Draft Hoods, Category I Appliances, and Appliances Listed for Use with Type B Vents
Annex G Recommended Procedure for Safety Inspection of an Existing Appliance Installation
Annex H Indoor Combustion Air Calculation Examples
Annex I Example of Combination of Indoor and Outdoor Combustion and Ventilation Opening Design
Annex J Enforcement
Annex K Informational References

THE NFPA HANDBOOKS DIFFER FROM CODES AND STANDARDS

Ever wonder what the difference is between an NFPA^® handbook and a code or standard? We’re glad you asked.

NFPA codes and standards both provide requirements for achieving outcomes. Handbooks take a deeper dive, providing the full text of a code or standard as well as expert commentary and features such as graphics, decision trees, testing procedures, case studies, sample forms and checklists, and other helpful aids to give a better understanding of the reasoning behind the requirements and how to apply them.

JUST REMEMBER:

• A code or standard is a framework—a set of rules to follow with a goal to achieve a certain result
• A handbook is a connector—linking requirements to application by helping you understand the reasoning behind a code or standard

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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• Calculating Pipe Size Using the Longest Length Method
• Calculating Pipe Size Using the Branch Length Method
• Sizing Combustion Air Using the Standard Method
• Sizing Combustion Air Using the KAIR Method
• Calculating the Size of Combustion Air Openings
• Calculating the Size of Reduced Building Area Openings
• Calculating Vent Size for Single Appliance
• Calculating Vent Size for Two (or more) Appliances

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