← All free practice sets

NO SIGN-UP REQUIRED

Free Fuel Gas Code Practice — IFGC 2021 practice questions (2026)

What is the format? These ten original multiple-choice questions introduce Fuel Gas Code Practice — IFGC 2021 study topics. They are practice material, not actual exam items. Official assessments may use different formats; check the current candidate guide for your credential.

What does this prepare me for? General code practice. Not aligned to any specific state exam blueprint. Check your licensing authority’s current bulletin. CodeReady does not confer a license.

What should I study? Start with pipe sizing and testing, venting and combustion air, installation and safety. This bank uses IFGC 2021 (ICC); general practice. Check the current exam objectives, adopted editions, and permitted references before planning your study.

How should I practice? Choose an answer before opening the explanation. Read the cited reference and revisit unfamiliar topics. These samples are general preparation, not jurisdiction-specific advice.

Explore full Fuel Gas Code Practice — IFGC 2021 →

1 / Pipe sizing and testing

A natural-gas system uses the longest-length method. The most remote outlet is 85 feet from the delivery point, and another appliance is only 25 feet away. Which table-length row is used to size the shorter branch when the table lists 80 and 90 feet?

  1. The 20-foot row
  2. The 30-foot row
  3. The 80-foot row
  4. The 90-foot row
Show answer & explanation

The 90-foot row

The longest-length method uses the distance to the most remote outlet for each section, together with that section's own load. Select the next listed length that is not shorter than 85 feet: 90 feet.

IFGC 2021 402.4.1; Table 402.4(2)

2 / Installation and safety

The gas supplier delivers 5 psi to a system serving appliances designed for 14 inches water column or less. Besides normal pressure regulation, what protection is required?

  1. Only an additional manual valve that someone must close after failure
  2. Overpressure protection limiting appliance pressure to 2 psi or less on line-regulator failure
  3. Only a larger sediment trap
  4. No additional protection because a regulator is installed
Show answer & explanation

Overpressure protection limiting appliance pressure to 2 psi or less on line-regulator failure

Delivery above 2 psi to these low-pressure appliances triggers overpressure protection. On line-regulator failure, the protective device must limit pressure to each connected appliance to 2 psi or less; this is a failure limit, not the normal operating-pressure setting.

IFGC 2021 416.1; 416.2.1

3 / Pipe sizing and testing

What minimum initial supply pressure is identified for the intended use of natural-gas Table 402.4(3)?

  1. 5 inches water column
  2. 2 inches water column
  3. 8 inches water column
  4. 2 psi
Show answer & explanation

8 inches water column

Table 402.4(3) identifies initial supply of 8 inches w.c. or greater and a 3-inch-w.c. design drop, with inlet below 2 psi and SG 0.60. Appliance inlet requirements remain controlling.

IFGC 2021 Table 402.4(3); 402.6

4 / Pipe sizing and testing

Which proposed use of aluminum-alloy gas tubing violates its location restriction?

  1. An underground outdoor run
  2. An approved protected indoor run
  3. An indoor run joined with appropriate fittings
  4. An indoor run with required corrosion protection
Show answer & explanation

An underground outdoor run

Aluminum-alloy tubing is not permitted outdoors or underground. Coating alone does not remove that prohibition.

IFGC 2021 403.4.4

5 / Pipe sizing and testing

A single closed valve separates live fuel gas from an adjacent pressure-test section. No double-block-and-bleed arrangement is present. Is that permitted as the test bulkhead?

  1. No; that single-valve separation is prohibited
  2. Yes; if the test medium is air
  3. Yes; if only one worker is present
  4. Yes; whenever the handle is locked
Show answer & explanation

No; that single-valve separation is prohibited

Section 406.1.4 prohibits using a valve as that bulkhead except with a double-block-and-bleed system; valve pressure capability must also be established.

IFGC 2021 406.1.4

6 / Venting and combustion air

A designer changes a single Category I installation from direct connection to Type B vent to a single-wall metal connector feeding Type B vent. Which table corresponds to the revised construction?

  1. Table 402.4(2)
  2. Table 504.2(2)
  3. Table 504.3(1)
  4. Table 504.2(1) without changing anything
Show answer & explanation

Table 504.2(2)

Table 504.2(2) is the single-appliance Type B vent table with a single-wall connector. The table construction assumptions must match the actual system.

IFGC 2021 Tables 504.2(1) and 504.2(2)

7 / Venting and combustion air

A clay-tile-lined exterior chimney serves two NAT appliances. Which checks replace reliance on a single interior-chimney maximum-capacity table?

  1. Only outdoor design temperature, with no input checks
  2. Combined maximum in 504.3(6a), each space-heater minimum in 504.3(6b), and connector sizing under 504.3(3)
  3. Only the largest appliance's flue-collar diameter
  4. Only total input against Table 504.3(1)
Show answer & explanation

Combined maximum in 504.3(6a), each space-heater minimum in 504.3(6b), and connector sizing under 504.3(3)

The exterior NAT + NAT path requires the paired maximum/minimum checks and Type B connectors. Minimum space-heater input addresses cold-chimney performance.

IFGC 2021 504.3.20; Tables 504.3(6a), 504.3(6b) and 504.3(3)

8 / Venting and combustion air

An all-mechanical combustion-air system serves 300,000 Btu/h of appliance input, with no other ventilation load in this calculation. What minimum outdoor airflow is required?

  1. 35 cfm
  2. 1,050 cfm
  3. 300 cfm
  4. 105 cfm
Show answer & explanation

105 cfm

Mechanical combustion air = (300,000 / 1,000) × 0.35 = 105 cfm. Makeup and other ventilation demands, if present, must be addressed separately.

IFGC 2021 304.9

9 / Installation and safety

May fuel gas be blown through newly installed piping to remove construction debris?

  1. Yes; if performed before the pressure test
  2. Yes; if no appliance is connected
  3. No; flammable or combustible gas is prohibited for debris removal
  4. Yes; if the gas is natural gas rather than propane
Show answer & explanation

No; flammable or combustible gas is prohibited for debris removal

Section 404.18 prohibits using flammable or combustible gas for pipe cleaning. Controlled purging under 406.7 is a different operation.

IFGC 2021 404.18

10 / Installation and safety

Two regulators have relief vents. May those relief-vent pipes be combined into a manifold merely because breather vents sometimes can be?

  1. Yes; if the smaller pipe is used for the manifold
  2. Yes; all regulator vent types can share one pipe
  3. No; regulator relief vents must terminate indoors
  4. No; relief and combination relief/breather vents serve one device independently to outdoors
Show answer & explanation

No; relief and combination relief/breather vents serve one device independently to outdoors

Section 410.3.1 allows an approved manifold design for breather-only vents, not relief or combined relief/breather vents. Those run independently outdoors.

IFGC 2021 410.3.1

Keep the momentum.

Unlock the full bank, practice modes, and explanations.

Get the full practice bank →