NFPA 54: National Fuel Gas Code Handbook, 2012 Edition

Contents

Preface

History of the National Fuel Gas Code

About the Contributors

About the Editor

PART ONE

NFPA 54, National Fuel Gas Code, 2012 Edition, with Commentary

1 Administration

1.1 Scope

1.2 Purpose

1.3 Retroactivity

1.4 Equivalency

1.5 Enforcement

2 Referenced Publications

2.1 General

2.2 NFPA Publications

2.3 Other Publications

2.4 References for Extracts in Mandatory Sections

3 Definitions

3.1 General

3.2 NFPA Official Definitions

3.3 General Definitions

4 General

4.1 Qualified Agency

4.2 Interruption of Service

4.3 Prevention of Accidental Ignition

5 Gas Piping System Design, Materials, and Components

5.1 Piping Plan

5.2 Provision for Location of Point of Delivery

5.3 Interconnections Between Gas Piping Systems

5.4 Sizing of Gas Piping Systems

5.5 Piping System Operating Pressure Limitations

5.6 Acceptable Piping Materials and Joining Methods

5.7 Gas Meters

5.8 Gas Pressure Regulators

5.9 Overpressure Protection Devices

5.10 Back Pressure Protection

5.11 Low-Pressure Protection

5.12 Shutoff Valves

5.13 Excess Flow Valve(s)

5.14 Expansion and Flexibility

6 Pipe Sizing

6.1 Pipe Sizing Methods

6.2 Tables for Sizing Gas Piping Systems Using Natural Gas

6.3 Tables for Sizing Gas Piping Systems Using Propane

6.4 Sizing Equations

7 Gas Piping Installation

7.1 Piping Underground

7.2 Installation of 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 Branch Pipe Connection

7.9 Manual Gas Shutoff Valves

7.10 Prohibited Devices

7.11 Systems Containing Gas–Air Mixtures Outside the Flammable Range

7.12 Systems Containing Flammable Gas–Air Mixtures

7.13 Electrical Bonding and Grounding

7.14 Electrical Circuits

7.15 Electrical Connections

8 Inspection, Testing, and Purging

8.1 Pressure Testing and Inspection

8.2 Piping System Leak Check

8.3 Purging Requirements

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

10 Installation of Specific Appliances

10.1 General

10.2 Air-Conditioning Appliances (Gas-Fired Air Conditioners and Heat Pumps)

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 Non-Recirculating Direct Gas-Fired Industrial Air Heaters

10.9 Recirculating Direct Gas-Fired Industrial Air Heaters

10.10 Duct Furnaces

10.11 Floor Furnaces

10.12 Food Service Appliance, Floor-Mounted

10.13 Food Service Appliances, Counter Appliances

10.14 Hot Plates and Laundry Stoves

10.15 Household Cooking Appliances

10.16 Illuminating Appliances

10.17 Incinerators, Commercial-Industrial

10.18 Infrared Heaters

10.19 Open-Top Broiler Units

10.20 Outdoor Cooking Appliances

10.21 Pool Heaters

10.22 Refrigerators

10.23 Room Heaters

10.24 Stationary Gas Engines

10.25 Gas-Fired Toilets

10.26 Unit Heaters

10.27 Wall Furnaces

10.28 Water Heaters

10.29 Compressed Natural Gas (CNG) Vehicular Fuel Systems

10.30 Appliances for Installation in Manufactured Housing

10.31 Fuel Cell Power Plants

10.32 Outdoor Open Flame Decorative Appliances

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

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

13 Sizing of Category I Venting Systems

13.1 Additional Requirements to Single Appliance Vent

13.2 Additional Requirements to Multiple-Appliance Vent

Annexes

A Explanatory Material

B Sizing and Capacities of Gas Piping

C Suggested Method of Checking for Leakage

D Suggested Emergency Procedure for Gas Leaks

E Flow of Gas Through Fixed Orifices

F Sizing of Venting Systems Serving Appliances Equipped with Draft Hoods, Category I Appliances, and Appliances Listed for Use with Type B Vents

G Recommended Procedure for Safety Inspection of an Existing Appliance Installation

H Indoor Combustion Air Calculation Examples

I Example of Combination of Indoor and Outdoor Combustion and Ventilation Opening Design

J Other Useful Definitions

K Enforcement

L Informational References

PART TWO

Supplements

1 Development of Revised Venting Guidelines

2 Fuel Gas Odorization

3 Procedure to Estimate Infiltration Rate for Residential Structures

4 Calculation Worksheets

5 Clearance Distance for Gas Appliance Sidewall Venting

6 Purging

7 Technical/Substantive Changes from the 2009 Edition to the 2012 Edition of NFPA 54

Index

Important Notices and Legal Disclaimers