TEXAS TRADESMAN PLUMBER-LIMITED
LICENSE PRACTICE EXAM 2025-2026
QUESTIONS AND ANSWERS WITH
VERIFIED RATIONALES
Master the 2025–2026 Texas State Board of
Plumbing Examiners licensing exam with this
comprehensive question practice test bank. Each
multiple-choice question features verified correct
answers paired with deep, code-verified rationales
based on the International Residential Code and
Texas Plumbing License Law. Perfect for fast-tracked
independent study, this premium guide guarantees
the technical clarity and confidence needed to pass
your Tradesman-Limited exam on the first attempt.
Questions 1–50
1. Which state body is solely responsible for regulating the plumbing
industry, administering examinations, and issuing licenses in Texas?
• A) Texas Department of Licensing and Regulation (TDLR)
• B) Texas Commission on Environmental Quality (TCEQ)
, • C) Texas State Board of Plumbing Examiners (TSBPE)
• D) Texas Department of Insurance (TDI)
• Correct Answer: C
• Rationale: The Texas State Board of Plumbing Examiners (TSBPE)
is the dedicated agency that enforces the Texas Plumbing License
Law, manages exam scheduling, and issues all credentials from
apprentice registrations to Master licenses.
2. A Tradesman Plumber-Limited license holder is legally permitted to
design or install plumbing systems in which type of structure?
• A) Multi-family apartment complexes up to four stories
• B) One- and two-family dwellings only
• C) Light commercial storefronts and strip malls
• D) Public school structures under 5,000 square feet
• Correct Answer: B
• Rationale: Texas plumbing regulations strictly limit the scope of
work for a Tradesman-Limited license holder to residential
plumbing within single-family houses and duplexes. Commercial
and larger residential jobs require a Journeyman or Master
license.
3. Under whose direct supervision must a Tradesman Plumber-Limited
licensee perform plumbing work?
• A) An elected municipal plumbing inspector
• B) A licensed Journeyman Plumber
, • C) A registered Plumbing Engineer
• D) A Responsible Master Plumber (RMP)
• Correct Answer: D
• Rationale: All work performed by a Tradesman Plumber-Limited
must be under the general supervision of a designated
Responsible Master Plumber (RMP) who holds the company's
master license.
4. To renew an active Tradesman Plumber-Limited license in the state
of Texas, how many hours of approved continuing education must be
completed annually?
• A) 4 hours
• B) 6 hours
• C) 8 hours
• D) 12 hours
• Correct Answer: B
• Rationale: TSBPE rules mandate that all active plumbing
licensees must complete 6 hours of approved Continuing
Professional Education (CPE) courses during each annual renewal
cycle.
5. What is the primary functional purpose of a plumbing trap installed
on a drainage fixture?
• A) To collect dropped jewelry and heavy debris safely
• B) To control the velocity of wastewater rushing down the stack
, • C) To form a water seal that prevents sewer gases from entering
rooms
• D) To equalize air pressure between the building and the city main
• Correct Answer: C
• Rationale: Liquid traps maintain a permanent water barrier (trap
seal) that physically blocks toxic, flammable, or foul-smelling
sewer gases from escaping into the living space.
6. What is the minimum legal trap size required for a standard
residential kitchen sink?
• A) 1-1/4 inches
• B) 1-1/2 inches
• C) 2 inches
• D) 3 inches
• Correct Answer: B
• Rationale: Plumbing codes enforce a minimum size of 1-1/2
inches for kitchen sink traps to accommodate the volume of
organic debris, food waste, and greases commonly introduced to
the drain.
7. When measuring an air gap to prevent back-siphonage into a
potable water supply, what is the minimum vertical separation
distance required?
• A) A flat 1 inch regardless of the pipe size
• B) Twice the effective diameter of the water supply pipe
LICENSE PRACTICE EXAM 2025-2026
QUESTIONS AND ANSWERS WITH
VERIFIED RATIONALES
Master the 2025–2026 Texas State Board of
Plumbing Examiners licensing exam with this
comprehensive question practice test bank. Each
multiple-choice question features verified correct
answers paired with deep, code-verified rationales
based on the International Residential Code and
Texas Plumbing License Law. Perfect for fast-tracked
independent study, this premium guide guarantees
the technical clarity and confidence needed to pass
your Tradesman-Limited exam on the first attempt.
Questions 1–50
1. Which state body is solely responsible for regulating the plumbing
industry, administering examinations, and issuing licenses in Texas?
• A) Texas Department of Licensing and Regulation (TDLR)
• B) Texas Commission on Environmental Quality (TCEQ)
, • C) Texas State Board of Plumbing Examiners (TSBPE)
• D) Texas Department of Insurance (TDI)
• Correct Answer: C
• Rationale: The Texas State Board of Plumbing Examiners (TSBPE)
is the dedicated agency that enforces the Texas Plumbing License
Law, manages exam scheduling, and issues all credentials from
apprentice registrations to Master licenses.
2. A Tradesman Plumber-Limited license holder is legally permitted to
design or install plumbing systems in which type of structure?
• A) Multi-family apartment complexes up to four stories
• B) One- and two-family dwellings only
• C) Light commercial storefronts and strip malls
• D) Public school structures under 5,000 square feet
• Correct Answer: B
• Rationale: Texas plumbing regulations strictly limit the scope of
work for a Tradesman-Limited license holder to residential
plumbing within single-family houses and duplexes. Commercial
and larger residential jobs require a Journeyman or Master
license.
3. Under whose direct supervision must a Tradesman Plumber-Limited
licensee perform plumbing work?
• A) An elected municipal plumbing inspector
• B) A licensed Journeyman Plumber
, • C) A registered Plumbing Engineer
• D) A Responsible Master Plumber (RMP)
• Correct Answer: D
• Rationale: All work performed by a Tradesman Plumber-Limited
must be under the general supervision of a designated
Responsible Master Plumber (RMP) who holds the company's
master license.
4. To renew an active Tradesman Plumber-Limited license in the state
of Texas, how many hours of approved continuing education must be
completed annually?
• A) 4 hours
• B) 6 hours
• C) 8 hours
• D) 12 hours
• Correct Answer: B
• Rationale: TSBPE rules mandate that all active plumbing
licensees must complete 6 hours of approved Continuing
Professional Education (CPE) courses during each annual renewal
cycle.
5. What is the primary functional purpose of a plumbing trap installed
on a drainage fixture?
• A) To collect dropped jewelry and heavy debris safely
• B) To control the velocity of wastewater rushing down the stack
, • C) To form a water seal that prevents sewer gases from entering
rooms
• D) To equalize air pressure between the building and the city main
• Correct Answer: C
• Rationale: Liquid traps maintain a permanent water barrier (trap
seal) that physically blocks toxic, flammable, or foul-smelling
sewer gases from escaping into the living space.
6. What is the minimum legal trap size required for a standard
residential kitchen sink?
• A) 1-1/4 inches
• B) 1-1/2 inches
• C) 2 inches
• D) 3 inches
• Correct Answer: B
• Rationale: Plumbing codes enforce a minimum size of 1-1/2
inches for kitchen sink traps to accommodate the volume of
organic debris, food waste, and greases commonly introduced to
the drain.
7. When measuring an air gap to prevent back-siphonage into a
potable water supply, what is the minimum vertical separation
distance required?
• A) A flat 1 inch regardless of the pipe size
• B) Twice the effective diameter of the water supply pipe
