ICC Journeyman Plumber with Gas - G28-N Exam Prep Guide

The ICC Journeyman Plumber with Gas - G28-N examination is designed for plumbing professionals preparing to demonstrate their knowledge of plumbing systems, water distribution, sanitary drainage, venting, fixtures, traps, storm drainage, fuel-gas piping, combustion air, appliance connections, and safe installation practices.

The ICC Journeyman Plumber with Gas - G28-N exam prep collection includes a books and courses rental package, professionally highlighted and tabbed references, flexible online exam preparation, and a standard exam book package.

This guide explains the available G28-N preparation options, current examination details, approved references, major plumbing and gas study areas, calculation topics, and practical code-navigation strategies.

Available G28-N Exam Prep Packages

• ICC Journeyman Plumber with Gas - G28-N - Books & Courses Rental Package: $790.00 sale price, reduced from $1,090.00
• ICC Journeyman Plumber with Gas - G28-N Highlighted & Tabbed Book Package: $495.00 sale price, reduced from $695.00
• ICC Journeyman Plumber with Gas - G28-N - Online Exam Prep: $295.00 sale price, reduced from $395.00
• ICC Journeyman Plumber with Gas - G28-N Exam Book Package: $129.00 sale price, reduced from $229.00

The rental package combines temporary book access with online training. The highlighted and tabbed package supports faster navigation between plumbing and fuel-gas topics. The online course is suitable for candidates who already own the correct references, while the exam book package supports independent study.

Books & Courses Rental Package

The ICC Journeyman Plumber with Gas - G28-N Books & Courses Rental Package combines temporary access to the assigned plumbing and fuel-gas references with structured online exam preparation.

The package is listed at a sale price of $790.00, reduced from the regular price of $1,090.00.

This package may be appropriate for candidates who:

• Need both exam references and the online course
• Do not currently own the approved code books
• Want an organized plumbing and gas study plan
• Need help navigating two separate references
• Want practice with plumbing and gas calculations
• Prefer combining lessons, books, and exam-style questions

Candidates should review the current product listing for rental periods, course access, shipping details, deposit requirements, and return instructions.

Highlighted & Tabbed Book Package

The ICC Journeyman Plumber with Gas - G28-N Highlighted & Tabbed Book Package provides professionally organized references for candidates who want to begin studying without preparing each book themselves.

The package is listed at a sale price of $495.00, reduced from the regular price of $695.00.

The prepared references may help candidates locate:

• Plumbing definitions and general regulations
• Fixture and water heater requirements
• Water-supply sizing tables
• Sanitary drainage and venting provisions
• Traps, interceptors, and storm drainage
• Fuel-gas piping and sizing tables
• Pressure regulators and appliance connections
• Combustion-air and venting requirements

Highlighted and tabbed books can improve navigation, but candidates must still understand how to interpret tables, definitions, exceptions, and installation requirements.

Online Exam Prep

The ICC Journeyman Plumber with Gas - G28-N Online Exam Prep course provides flexible, self-paced preparation for candidates who already own the correct references or plan to purchase them separately.

The course is listed at a sale price of $295.00, reduced from the regular price of $395.00.

Online preparation may help candidates:

• Review plumbing and gas subjects in a logical order
• Practice water, drainage, vent, and gas calculations
• Improve code-book navigation
• Review plan-reading questions
• Identify weak knowledge areas
• Complete exam-style practice questions
• Study around an active plumbing schedule

The course is most effective when candidates use both approved references while completing lessons and practice questions.

Exam Book Package

The ICC Journeyman Plumber with Gas - G28-N Exam Book Package provides the printed references associated with the examination for independent preparation.

The package is listed at a sale price of $129.00, reduced from the regular price of $229.00.

This package may be appropriate for candidates who:

• Prefer independent book-based study
• Want to own the exam references
• Already understand many plumbing and gas subjects
• Want to create a personalized tab and highlighting system
• Already have separate training or practice questions
• Need the references for continued professional use

What Is the ICC G28-N Examination?

The G28-N examination is the ICC National Standard Journeyman Plumber with Gas examination. Participating jurisdictions may use it as part of a journeyman plumber, plumber with gas, or combined plumbing and gas-fitting qualification process.

The examination includes 70 multiple-choice questions with a three-hour time limit. Candidates must earn at least 70 percent to pass.

The examination is open book, subject to current ICC rules for approved references, permanent tabs, highlighting, handwritten notes, inserted materials, and book condition.

Passing G28-N does not automatically issue a plumbing or gas-fitting license. Candidates must also satisfy the experience, application, supervision, insurance, registration, and fee requirements established by the applicable licensing authority.

G28-N Exam References

The current G28-N examination information identifies two primary references:

• International Plumbing Code, 2018 Edition
• International Fuel Gas Code, 2018 Edition

The International Plumbing Code supports preparation involving fixtures, water heaters, water supply and distribution, sanitary drainage, vents, traps, interceptors, separators, storm drainage, and plumbing system testing.

The International Fuel Gas Code supports preparation involving gas piping, pipe sizing, regulators, valves, appliance connections, pressure testing, combustion air, chimneys, vents, and fuel-gas safety.

Candidates should confirm the approved editions before registering because examination references can change.

G28-N Examination Content

The current examination outline assigns questions across plumbing and gas subjects, including:

• Administration and General Regulations: 34%
• Plumbing Fixtures: 11%
• Water Supply and Distribution: 11%
• Sanitary Drainage: 9%
• Plumbing Vent Requirements: 7%
• Traps, Interceptors, and Separators: 7%
• Storm Drainage: 2%
• Gas Piping: 19%

Candidates should prepare across the complete outline instead of concentrating only on the work they perform most often.

Confirm Local Licensing Requirements

Before purchasing materials or scheduling the examination, candidates should verify:

• Whether the licensing authority accepts G28-N
• The scope of the plumber-with-gas classification
• The required plumbing and fuel-gas code editions
• The current approved reference list
• The question count, testing time, and passing score
• Rules for tabs, highlighting, and notes
• Required plumbing and gas-fitting experience
• Apprenticeship or education requirements
• Application and examination fees
• Required supervision
• License renewal and continuing-education requirements

What Does a Journeyman Plumber with Gas Do?

A journeyman plumber with gas installs, alters, repairs, tests, and maintains plumbing and fuel-gas systems within the scope permitted by the applicable licensing authority.

Common responsibilities may include:

• Reading plumbing and gas piping plans
• Installing water service and distribution piping
• Installing sanitary drainage and vent systems
• Connecting plumbing fixtures and water heaters
• Installing natural gas and propane piping
• Sizing gas piping for connected appliances
• Installing valves, regulators, and connectors
• Testing plumbing and fuel-gas systems
• Installing combustion-air openings and venting
• Correcting code deficiencies
• Coordinating permits and inspections
• Following jobsite and fuel-gas safety procedures

Plumbing Code Administration

Journeyman candidates should understand how plumbing work moves through permitting, inspection, testing, correction, and final approval.

Study subjects may include:

• Permit requirements
• Construction documents
• Required inspections
• Approved materials and methods
• Alternative materials
• Equipment access
• Protection of piping
• System testing
• Unsafe conditions
• Installer responsibilities

Plumbing Fixtures

Fixture requirements address approved products, installation, clearances, water connections, drainage connections, and accessibility.

Common fixtures include:

• Water closets
• Urinals
• Lavatories
• Kitchen sinks
• Service sinks
• Bathtubs and showers
• Drinking fountains
• Clothes-washing machines
• Floor drains
• Emergency fixtures

Candidates should review fixture-unit values, required clearances, traps, supports, waste connections, and water-supply connections.

Water Heaters

Water heater questions may involve installation location, capacity, clearances, temperature control, pressure protection, combustion air, venting, and drainage.

Candidates should review:

• Temperature and pressure relief valves
• Relief discharge piping
• Drain pans
• Cold-water shutoff valves
• Thermal expansion control
• Combustion-air requirements
• Chimneys and vents
• Garage installation
• Access for service
• Protection from physical damage

Water Supply and Distribution

Water distribution systems must provide potable water at suitable pressure and flow to every required fixture and appliance.

Study subjects may include:

• Water service piping
• Water distribution piping
• Water-supply fixture units
• Developed length
• Available water pressure
• Elevation pressure loss
• Pressure-reducing valves
• Water hammer control
• Thermal expansion
• Hot-water distribution
• Recirculation systems
• Pipe insulation

Water Pipe-Sizing Calculations

Water pipe sizing may require candidates to use fixture units, developed length, available pressure, elevation, and pressure-loss information.

A practical process includes:

• Identify the fixtures served
• Determine the water-supply fixture units
• Calculate developed piping length
• Determine available supply pressure
• Account for elevation and equipment losses
• Select the correct sizing table
• Choose a pipe size with adequate capacity

Backflow Prevention

Backflow prevention protects potable water from contamination caused by backsiphonage or backpressure.

Candidates should review:

• Air gaps
• Atmospheric vacuum breakers
• Pressure vacuum breakers
• Reduced-pressure-principle assemblies
• Double-check assemblies
• Hose connection vacuum breakers
• Required device locations
• Installation clearances
• Testing and accessibility

The degree of hazard and type of potential backflow determine the required protection.

Sanitary Drainage Systems

Sanitary drainage systems carry wastewater from fixtures to the building sewer or another approved disposal point.

Important subjects include:

• Drainage fixture units
• Fixture drains
• Horizontal branches
• Vertical stacks
• Building drains
• Building sewers
• Drainage pipe sizing
• Required pipe slope
• Changes in direction
• Cleanouts
• Sumps and ejectors
• System testing

Drainage Fixture Units and Pipe Sizing

Drainage fixture units represent the probable discharge load produced by plumbing fixtures.

Candidates may need to:

• Determine individual fixture-unit values
• Add fixture units on a branch
• Calculate stack loads
• Calculate building drain loads
• Select pipe sizes from drainage tables
• Apply required slopes
• Interpret table notes and exceptions

The correct sizing table depends on whether the piping is horizontal, vertical, a building drain, or a building sewer.

Cleanouts

Cleanouts provide access for inspection, cleaning, and removal of drainage obstructions.

Candidates should review:

• Required cleanout locations
• Maximum cleanout spacing
• Changes in direction
• Building drain and sewer cleanouts
• Stack cleanouts
• Cleanout size
• Required access and clearance
• Protection from physical damage

Plumbing Vent Systems

Vent systems protect trap seals and allow drainage systems to operate at atmospheric pressure.

Common venting methods include:

• Individual vents
• Common vents
• Wet vents
• Circuit vents
• Stack vents
• Vent stacks
• Relief vents
• Island fixture vents
• Combination waste and vent systems
• Air admittance valves where permitted

Candidates should identify the venting method before applying sizing, connection, and installation requirements.

Vent Sizing and Trap Arms

Vent size may depend on connected drainage fixture units, developed vent length, and the drainage piping served.

Trap-arm questions may involve:

• Trap-arm pipe size
• Maximum developed length
• Required slope
• Distance from the trap to the vent
• Changes in direction
• Prohibited arrangements
• Protection of the trap seal

Candidates should practice using vent-sizing and trap-arm tables under timed conditions.

Traps, Interceptors, and Separators

Fixture traps prevent sewer gases from entering occupied spaces. Interceptors and separators remove grease, oil, sand, lint, solids, and other materials before they enter the drainage system.

Study subjects may include:

• Trap-seal depth
• Trap size
• Prohibited traps
• Double trapping
• Trap primers
• Grease interceptors
• Oil separators
• Sand interceptors
• Lint and hair interceptors
• Access, venting, and maintenance

Storm Drainage

Storm drainage systems remove rainwater from roofs and other approved surfaces.

Study subjects may include:

• Roof drainage areas
• Rainfall rates
• Roof drains
• Gutters
• Leaders and conductors
• Horizontal storm piping
• Secondary drainage
• Overflow drains
• Scuppers
• Discharge locations

Candidates should understand how roof area and rainfall rate affect drain, conductor, and horizontal pipe sizing.

Fuel-Gas Piping

Fuel-gas piping must deliver sufficient gas to connected appliances while maintaining the required operating pressure.

Important preparation subjects include:

• Natural gas and propane characteristics
• Connected appliance demand
• Pipe-sizing tables
• Developed length
• Steel piping
• Corrugated stainless steel tubing
• Underground plastic piping
• Joints and fittings
• Pipe support and protection
• Corrosion protection
• Pressure testing
• Leak detection

Gas Pipe-Sizing Calculations

Gas pipe sizing may depend on fuel type, system pressure, permitted pressure drop, pipe material, specific gravity, developed length, and connected demand.

A practical sizing process includes:

• List all connected gas appliances
• Determine each appliance input rating
• Calculate the load carried by each pipe section
• Determine the applicable developed length
• Select the correct fuel, pressure, and material table
• Choose a pipe size with sufficient capacity

Candidates should avoid mixing natural gas, propane, low-pressure, and elevated-pressure sizing tables.

Gas Piping Materials and Joints

Gas piping materials and joining methods must be approved for the fuel, pressure, installation location, and environmental conditions.

Possible materials and joints include:

• Steel pipe and threaded joints
• Welded steel piping
• Copper-alloy tubing where permitted
• Corrugated stainless steel tubing
• Polyethylene underground piping
• Flared connections
• Mechanical fittings
• Heat-fusion joints
• Listed transition fittings

Gas Valves and Regulators

Valves and regulators control gas flow and protect downstream appliances from improper pressure.

Candidates should review:

• Building shutoff valves
• Branch shutoff valves
• Appliance shutoff valves
• Line pressure regulators
• Appliance regulators
• Regulator capacity
• Regulator venting
• Overpressure protection
• Valve accessibility
• Appliance connectors
• Sediment traps

Gas Piping Pressure Testing

New and altered gas piping must be tested before concealment or operation.

Important preparation topics include:

• Approved test media
• Test pressure
• Test duration
• Gauge range and accuracy
• Isolation of appliances and regulators
• Inspection of exposed joints
• Repair and retesting
• Approved leak-detection methods
• Pressure-test safety

Open flames should never be used to locate gas leaks, and oxygen should not be used as a gas piping test medium.

Combustion Air

Fuel-burning appliances require sufficient air for combustion, dilution, and ventilation.

Combustion-air requirements may depend on:

• Total appliance input
• Room volume
• Building construction
• Indoor openings
• Outdoor openings
• Horizontal or vertical ducts
• Mechanical combustion air
• Louver and grille free area
• Competing exhaust systems
• Appliance type

Candidates should identify the combustion-air method before calculating the required opening or mechanical airflow.

Chimneys and Vents

Chimneys and vents carry combustion products safely outdoors.

Important study subjects include:

• Masonry chimneys
• Factory-built chimneys
• Type B gas vents
• Special gas vents
• Vent connectors
• Common venting
• Vent sizing
• Connector slope and support
• Clearance to combustible materials
• Vent termination
• Condensing appliances
• Manufacturer instructions

Gas-Fired Appliances

Common gas-fired appliances that may appear in G28-N preparation include:

• Water heaters
• Furnaces
• Boilers
• Ranges and ovens
• Clothes dryers
• Commercial cooking appliances
• Unit heaters
• Fireplaces
• Pool heaters
• Standby generators

For each appliance, candidates should review gas demand, valves, regulators, connectors, sediment traps, combustion air, venting, clearances, and service access.

Plan Reading

Plan-reading questions may require candidates to interpret plumbing plans, riser diagrams, isometric drawings, gas piping diagrams, fixture schedules, and equipment information.

Study subjects may include:

• Water piping plans
• Sanitary drainage plans
• Vent riser diagrams
• Storm drainage plans
• Gas piping layouts
• Pipe sizes and slopes
• Fixture and appliance schedules
• Valve and regulator locations
• Developed piping lengths
• Plan symbols and abbreviations

System Testing and Inspection

Plumbing and gas systems may require testing before piping is concealed or placed into service.

Study areas may include:

• Water piping pressure tests
• Drainage and vent tests
• Water and air tests
• Gas piping pressure tests
• Approved test equipment
• Test pressure and duration
• Leak inspection
• Repair and retesting
• Inspection documentation
• Final system approval

Plumbing and Gas Safety

Plumbing and gas-fitting work may involve excavations, pressurized systems, combustible fuel, hot work, confined spaces, ladders, and power tools.

Important safety subjects include:

• Personal protective equipment
• Trenching and excavation safety
• Confined-space awareness
• Hot-work precautions
• Pressure-test safety
• Lockout and tagout
• Control of ignition sources
• Combustible gas monitoring
• Carbon monoxide awareness
• Emergency gas-leak response
• Protection of occupants and property

Code-Book Navigation

An open-book examination still requires fast and accurate reference navigation.

A practical lookup method includes:

• Read the complete question
• Identify whether the subject is plumbing or fuel gas
• Select the International Plumbing Code or International Fuel Gas Code
• Use the index or table of contents
• Locate the complete section, table, or figure
• Review definitions, footnotes, and exceptions
• Confirm that the requirement applies to the stated system
• Record difficult topics for additional practice

Candidates should practice choosing the correct reference before searching for the exact answer.

Recommended Study Plan

• Review exam rules and reference-book organization
• Study plumbing and fuel-gas definitions
• Review fixtures and water heaters
• Practice water-supply pipe sizing
• Study backflow prevention
• Practice sanitary drainage calculations
• Review vent types and vent sizing
• Study traps, interceptors, and storm drainage
• Practice natural gas and propane pipe sizing
• Review valves, regulators, and pressure testing
• Study combustion air and venting
• Practice plan reading
• Complete timed code-navigation exercises
• Review every missed practice question

Which G28-N Package Should You Choose?

• Choose the Books & Courses Rental Package for temporary access to both references and structured online preparation.
• Choose the Highlighted & Tabbed Book Package for professionally organized plumbing and fuel-gas references.
• Choose Online Exam Prep when you already own the correct books and want guided study.
• Choose the Exam Book Package for independent preparation and permanent book ownership.

FAQ

Q. What is the ICC Journeyman Plumber with Gas - G28-N exam?

A. It is an ICC Contractor and Trades examination used by participating jurisdictions to evaluate journeyman-level plumbing and fuel-gas knowledge.

Q. How much does the Books & Courses Rental Package cost?

A. The sale price is $790.00, reduced from the regular price of $1,090.00.

Q. How much does the Highlighted & Tabbed Book Package cost?

A. The sale price is $495.00, reduced from the regular price of $695.00.

Q. How much does Online Exam Prep cost?

A. The sale price is $295.00, reduced from the regular price of $395.00.

Q. How much does the Exam Book Package cost?

A. The sale price is $129.00, reduced from the regular price of $229.00.

Q. What books are used for G28-N?

A. The current approved references are the 2018 International Plumbing Code and 2018 International Fuel Gas Code.

Q. How many questions are on the G28-N examination?

A. The examination currently includes 70 multiple-choice questions.

Q. How much time is allowed?

A. Candidates currently have three hours to complete the examination.

Q. What score is required to pass?

A. Candidates must currently answer at least 70 percent of the questions correctly.

Q. Is the G28-N examination open book?

A. Yes. Candidates may use approved references subject to current ICC testing rules.

Q. What subjects should I study?

A. Study administration, fixtures, water supply, sanitary drainage, vents, traps, storm drainage, gas piping, regulators, testing, combustion air, and appliance venting.

Q. Should I practice both water and gas pipe-sizing calculations?

A. Yes. The examination includes plumbing distribution and fuel-gas piping subjects.

Q. Should I study plan reading?

A. Yes. Candidates should practice plumbing plans, riser diagrams, isometrics, gas piping layouts, and equipment schedules.

Q. Does passing G28-N automatically issue a plumbing or gas license?

A. No. The applicable licensing authority controls experience, applications, supervision, fees, insurance, and final approval.

Q. Where can I purchase the G28-N packages?

A. The available options can be found in the ICC Journeyman Plumber with Gas - G28-N exam prep collection.

Conclusion

The ICC Journeyman Plumber with Gas - G28-N examination requires candidates to combine practical plumbing experience with fuel-gas knowledge and efficient navigation of two code references.

Important preparation subjects include fixtures, water heaters, water supply, sanitary drainage, venting, traps, storm drainage, gas piping, pipe sizing, valves, regulators, pressure testing, combustion air, appliance venting, and plan reading.

1 Exam Prep offers a Books & Courses Rental Package, Highlighted & Tabbed Book Package, Online Exam Prep, and Exam Book Package for different preparation needs and budgets.

Shop ICC Journeyman Plumber with Gas - G28-N Exam Prep

Key Takeaways

• G28-N is the ICC National Standard Journeyman Plumber with Gas examination.
• The Books & Courses Rental Package sale price is $790.00.
• The Highlighted & Tabbed Book Package sale price is $495.00.
• The Online Exam Prep sale price is $295.00.
• The Exam Book Package sale price is $129.00.
• The exam currently includes 70 questions and a three-hour limit.
• The passing requirement is 70 percent.
• The examination is open book under current testing rules.
• The references are the 2018 International Plumbing Code and 2018 International Fuel Gas Code.
• The exam combines plumbing, drainage, venting, water-supply, and fuel-gas subjects.
• Passing G28-N does not automatically issue a plumbing or gas-fitting license.
• Candidates should verify current exam and jurisdictional requirements before registering.