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ICC F34 Journeyman Gas Pipe Fitter Exam (2015 IFGC)

National · Pearson Vue

Verified, not estimated. Every figure below is drawn from the official exam structure we maintain — question counts, passing standard and topic weighting. Practice questions are grounded in the source law with statute citations. We omit any figure we can't verify rather than guess at it.

Total questions

Passing score

70%

Exam time

120 min

Administered by

Pearson Vue

Format

Reference materials allowed

National State Portion 55 questions

General Requirements 22 Q · 40%

General Installation RequirementsCode Definitions and TermsPlan ReadingTestingMaterialsPermits and Permit RequirementsInspections and Inspection TypesAppliance Location and Prohibited LocationsClearances to Combustible ConstructionElectrical Bonding and Grounding of Gas PipingCode Official Authority and EnforcementAppliance Access and Service Space Requirements +1 more

Appliances and Equipment 13 Q · 24%

Requirements for Specific Appliances & EquipmentClearance requirements for specific appliancesClothes dryer exhaust duct installation and length limitationsUnvented room heater restrictions and oxygen-depletion safety systemsVented wall furnace and floor furnace placement and accessForced-air warm-air furnace return air prohibited sourcesTesting standards and listing requirements by appliance typeSauna heater combustion air, temperature controls, and safety noticesDirect-fired industrial air heater installation and ventilation requirements

Fuel Supply System Sizing 5 Q · 9%

Service and Distribution Pipe SizingMaximum Gas Demand Calculation (Total Connected Load)Allowable Pressure Drop and Minimum Appliance Supply PressurePipe Length Determination Methods (Longest Length, Branch Length, Hybrid Pressure)Sizing Tables and Equations for Different Pipe/Tubing Materials (Schedule 40 Steel, Copper, CSST, PE)Altitude Adjustment for Gas Demand Above 2,000 Feet ElevationMaximum Design Operating Pressure Limits for Interior Piping SystemsSizing for Existing System Modifications and Additional AppliancesGas Piping Installations

Combustion Air 7 Q · 13%

Combustion Air Source, Size of Ducts/OpeningsIndoor Combustion Air Volume Requirements (Standard and Known-ACH Methods)Outdoor Combustion Air Opening Methods (Two-Opening and One-Opening)Combination Indoor and Outdoor Combustion AirMechanical Combustion Air Supply Systems and Appliance InterlockLouvers, Grilles, and Screen Free-Area CalculationsCombustion Air Duct Construction and Installation RequirementsMakeup Air Requirements for Exhaust InterferenceProtection of Combustion Air From Corrosive or Flammable Fumes

Chimneys and Vents 8 Q · 15%

Venting, Vent Connector, and ChimneysAppliance venting categories and vent type selection (Types B, BW, L, single-wall metal)Vent and chimney termination height and location requirementsSizing of Category I venting systems using IFGC Section 504 tablesVent connector materials, clearances, slope, and length limitationsDraft hoods and draft control devices installation requirementsAppliances not required to be vented and aggregate input limitsMasonry chimney inspection, lining, and cleanout requirementsDirect-vent, mechanical draft, and positive-pressure venting system requirementsChimneys and Vents

Key Distinctions

Longest length method (Section 402.4.1)vsBranch length method (Section 402.4.2)

The longest length method sizes every section of the system from the single table row for the length to the most remote outlet, while the branch length method sizes each branch from that branch's own meter-to-outlet length (mains on the longest run still use the longest-run row).

IFGC Section 402.4.1, Longest Length Method; Table 402.4(2), Schedule 40 Metallic Pipe (natural gas, 0.5 in. w.c. drop)

Low-pressure gas sizing equation (Equation 4-1)vsHigh-pressure gas sizing equation (Equation 4-2)

Per 2015 IFGC Section 402.4, Equation 4-1 is used for systems operating at less than 1 1/2 psi and Equation 4-2 for systems at 1 1/2 psi and above (the 2 psi figure is only an inlet-pressure heading in certain capacity tables).

IFGC 2015 Section 402.4 (Equations 4-1 and 4-2)

Outdoor combustion air through openings direct to outdoors or vertical ductsvsOutdoor combustion air through horizontal ducts

Under Section 304.6.1 the two-permanent-openings method requires 1 square inch per 4,000 Btu/h for each opening communicating directly with the outdoors or through vertical ducts, versus 1 square inch per 2,000 Btu/h where horizontal ducts are used.

IFGC 2015 Section 304.6.1

Two-permanent-openings method (outdoor air)vsOne-permanent-opening method (outdoor air)

The two-opening method sizes each opening by Btu/h input (Section 304.6.1), while the one-opening method (Section 304.6.2), with the opening commencing within 12 inches of the top of the enclosure, additionally requires appliance clearances of not less than 1 inch from sides and back and 6 inches from the front.

IFGC 2015 Section 304.6.1

Indoor combustion air openings between spaces on the same story (Section 304.5.3.1)vsOpenings in floors connecting spaces in different stories (Section 304.5.3.2)

Same-story openings each need a minimum free area of 1 square inch per 1,000 Btu/h of total input but not less than 100 square inches, while openings in doors or floors joining different stories need a total minimum free area of 2 square inches per 1,000 Btu/h of total input.

IFGC 2015 Section 304.5.3.1

Furnace output rating capacityvsFurnace input rating

Section 618.2 sizes outdoor and return air ducts/openings from the furnace OUTPUT rating capacity (2 square inches per 1,000 Btu/h output); using the input rating is a common error.

IFGC 2015 Section 618.2

Thimble not less than 2 inches larger in diametervsThimble not less than 4, 6, or 12 inches larger in diameter

Section 503.7.7, Item 1 allows a ventilated thimble only 2 inches larger in diameter where there is a run of not less than 6 feet of metal pipe in the open between the draft hood outlet and the thimble; otherwise listed draft-hood appliances require 4 inches larger, with 6-inch and 12-inch figures applying to unlisted draft-hood appliances and to residential/low-heat appliances respectively.

IFGC 2015 Section 503.7.7

Gas vent 12 inches or less in size located not less than 8 feet from a vertical wallvsGas vent over 12 inches in size, or located less than 8 feet from a wall or similar obstruction

Per Section 503.6.4, the first case may terminate above a sloped roof in accordance with Figure 503.6.4, while the second must terminate not less than 2 feet above the roof penetration and 2 feet above any portion of a building within 10 feet horizontally.

IFGC 2015 Section 503.6.4

Medium-heat appliancevsLow-heat (residential) appliance

Under the Section 202 'Appliance Type' definitions, flue-entrance combustion products of a medium-heat appliance exceed 1,000°F but are not greater than 2,000°F, whereas at or below 1,000°F the appliance is a low-heat (residential) appliance.

IFGC 2015 Section 202 (definition of 'Appliance Type')

Pressure test duration of 1/2 hour per 500 cubic feetvsPressure test duration of not less than 10 minutes

Section 406.4.2 sets the general duration at not less than 1/2 hour for each 500 cubic feet of pipe volume or fraction thereof, but for a system of less than 10 cubic feet or a system in a single-family dwelling the duration shall be not less than 10 minutes.

IFGC 2015 Sections 406.4.1 and 406.4.2

Buildings within the scope of the IFGCvsBuildings excepted to the International Residential Code

Section 101.2 Exception sends detached one- and two-family dwellings and multiple single-family dwellings (townhouses) not more than three stories high with separate means of egress, plus their accessory structures, to the International Residential Code instead of the fuel gas code.

IFGC 2015 Section 101.2

Raw material (feedstock) piping — outside the code scopevsPiping to special atmosphere generators — within the code scope

Section 101.2.4, Item 3 excludes raw material/feedstock applications 'except for piping to special atmosphere generators,' so that generator piping remains regulated, while atomic energy plant fuel gas piping, railroad switch heating LP-gas systems, and temporary LP-gas piping not becoming part of the permanent system are outside the scope.

IFGC 2015 Section 101.2.4

Key Terms

Medium-heat appliance (Section 202, 'Appliance Type') IFGC 2015 Section 202 (definition of 'Appliance Type')

An appliance in which the products of combustion at the point of entrance to the flue, under normal operating conditions, have a temperature greater than 1,000°F but not greater than 2,000°F.

Board of appeals fuel gas member qualification (Section 109.2.1) IFGC 2015 Section 109.2.1

Where the fuel gas seat is filled by a contractor rather than a registered design professional, the member shall be a fuel gas contractor with not less than 10 years' experience, 5 of which shall have been in responsible charge of work.

Mechanical test gauge range (Section 406.4) IFGC 2015 Section 406.4

A mechanical gauge used to measure test pressures shall have a range such that the highest end of the scale is not greater than five times the test pressure.

Double block and bleed valve system (Section 406.1.4) IFGC 2015 Section 406.1.4

The only condition under which a valve in a line may serve as a bulkhead between gas in one section and test medium in an adjacent section when a system is pressure tested in sections.

Conduit for piping in a solid floor (Sections 404.8, 404.8.1) IFGC 2015 Sections 404.8 and 404.8.1

Where gas piping in a solid floor is installed in conduit with one end outdoors and the other extending into an occupiable portion of the building with the annular space sealed, the conduit shall extend not less than 4 inches outside the building, be vented above grade to the outdoors, prevent entrance of water and insects, and extend not less than 2 inches beyond the point where the pipe emerges from the floor.

Reduced clearance protective assembly (Section 308.2) IFGC 2015 Section 308.2

A manufactured assembly used in lieu of the prescribed Table 308.2 clearance-reduction methods, which must be listed and labeled in accordance with UL 1618.

Sauna heater warning notice (Section 615.4) IFGC 2015 Section 615.4

Where a non-direct-vent sauna heater's combustion air inlet and draft hood are in an adjoining dressing room, provisions must prevent blocking and contact or a warning notice must be posted that is easily readable, contrasts with its background, and uses letters not less than 1/4 inch (6.4 mm) high.

Alternative area method for chimney venting, two draft-hood appliances (Section 503.5.5, Item 3) IFGC 2015 Section 503.5.5

The effective area of the chimney flue shall be not less than the area of the larger draft hood outlet plus 50 percent of the area of the smaller draft hood outlet, and not greater than seven times the smallest draft hood outlet area.

Manifold-mounted appliance shutoff valve (Section 409.5.3) IFGC 2015 Section 409.5.3

An appliance shutoff valve may be installed at a manifold provided the manifold is readily accessible, permanently identified, and located within 50 feet of the appliance served, with piping from the manifold to within 6 feet of the appliance designed, sized and installed per Sections 401 through 408.

Q (input rate) in the sizing equations (Section 402.4) IFGC 2015 Section 402.4

Input rate of the appliance(s) expressed in cubic feet per hour at 60°F and 30-inch mercury column.

CSST bonding jumper length (Section 310.1.1.3) IFGC 2015 Section 310.1.1.3

The bonding jumper between the connection to the gas piping system and the connection to the grounding electrode system shall not exceed 75 feet in length.

Unvented room heater oxygen-depletion safety shutoff (Section 621.6) IFGC 2015 Section 621.6

A system that shuts off gas to the main and pilot burners at the oxygen concentration specified by the manufacturer but in no case lower than 18 percent, with no field adjustment means that could change the set point.

Appliances in public garages (Section 305.4) IFGC 2015 Section 305.4

Appliances shall be installed not less than 8 feet above the floor, and where motor vehicles can pass beneath, at the manufacturer's required clearances and not less than 1 foot higher than the tallest vehicle garage door opening.

Standard method, indoor combustion air (Sections 304.5, 304.5.1) IFGC 2015 Sections 304.5 and 304.5.1

Where the air infiltration rate is not known, the space must have a minimum volume of 50 cubic feet per 1,000 Btu/h of the total input rating of all appliances in the space.

Return air from a room containing an appliance (Section 618.4(5), Exception 2.1) IFGC 2015 Section 618.4

Permitted only where the room volume exceeds 1 cubic foot for each 10 Btu/h of combined input rating of all fuel-burning appliances in the room (with supply air returned approximately equal and inlets more than 10 feet from any draft hood).

Minimum test pressure (Section 406.4.1) IFGC 2015 Sections 406.4.1 and 406.4.2

The test pressure shall be not less than 1 1/2 times the proposed maximum working pressure, but not less than 3 psig.

Formulas to Know

Convert appliance Btuh to demand in cfh and table capacity back to Btuh (natural gas at 1,000 Btu per cubic foot)

cfh = Btuh ÷ 1,000; Btuh capacity = table cfh × 1,000 (e.g., 40,000 Btuh = 40 cfh; 247 cfh = 247,000 Btuh; 44 cfh = 44,000 Btuh)

Selecting the table length row (Table 402.4(2))

Use the measured length; where the table has no matching row, use the next longer row (15 ft → 20-ft row; 45 ft → 50-ft row; 75 ft → 80-ft row; 95 ft → 100-ft row)

Longest length method row and section sizing

Find the length from the meter to the most remote outlet, take that row (or next longer), and size every section in that one row for the load it carries; pick the smallest size whose capacity meets the load (e.g., 190 cfh in the 50-ft row: 3/4 in = 151 cfh too small, 1 in = 284 cfh)

Branch length method lengths

Each branch is sized on its own meter-to-outlet length (main run to tee + branch run; e.g., 15 + 8 = 23 ft → 30-ft row; 38 ft → 40-ft row; 50 ft → 50-ft row), while main sections are sized on the longest run length

Spare (excess) capacity of an installed pipe

Spare cfh = table capacity of installed size at that length − appliance demand in cfh (e.g., 137 − 80 = 57 cfh; 44 − 40 = 4 cfh; 322 − 150 = 172 cfh)

Minimum pressure test pressure (Section 406.4.1)Test pressure = 1 1/2 × proposed maximum working pressure, but not less than 3 psig (2 psig × 1.5 = 3 psig)

Maximum full-scale range of a mechanical test gauge (Section 406.4)Highest end of scale not greater than 5 × test pressure (5 × 3 psig = 15 psig maximum)

Minimum pressure test duration (Section 406.4.2)

Not less than 1/2 hour for each 500 cubic feet of pipe volume or fraction thereof (1,200 ÷ 500 = 2.4 → 3 increments × 1/2 hr = 1 1/2 hours); for a system under 10 cubic feet or in a single-family dwelling, not less than 10 minutes

Indoor combustion air, standard method minimum space volume (Section 304.5.1)Volume = total appliance input ÷ 1,000 × 50 cubic feet (120,000 ÷ 1,000 × 50 = 6,000 cubic feet)

Return/outdoor air duct or opening area for a forced-air furnace (Section 618.2)

Not less than 2 square inches of unobstructed area per 1,000 Btu/h of furnace OUTPUT rating capacity (120,000 ÷ 1,000 × 2 = 240 square inches), unless manufacturer's instructions state larger

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