Master / Journeyman Plumber Exam
Safety & General Practice Questions
20 practice questions with detailed explanations — aligned to the Master / Journeyman Plumber Exam.
Master Safety & General to boost your score on the Master / Journeyman Plumber Exam. Each question below mirrors the style and difficulty of real exam questions, complete with detailed explanations so you understand the why behind every answer. Work through all 20 questions, review any that trip you up, and use the related topics below to round out your preparation.
Q1.OSHA requires trench protection (shoring or shielding) for trenches deeper than:
A.3 feetB.4 feetC.5 feetD.6 feet✓C. 5 feetExplanation: OSHA 1926.652 requires protection from cave-ins for trenches 5 feet or deeper (unless in stable rock).
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Q2.Ladders must be provided in trenches deeper than 4 feet and spaced no more than ___ feet apart.
A.20B.25C.50D.100✓B. 25Explanation: OSHA requires egress (ladders) within 25 feet of lateral travel for workers in trenches 4 feet or deeper.
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Q3.Excavated soil (spoils) must be kept at least ___ feet back from the edge of the trench.
A.1B.2C.3D.4✓B. 2Explanation: OSHA requires spoil piles to be at least 2 feet from the edge to prevent them from falling back in or causing collapse.
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Q4.What type of fire extinguisher is best for a fire involving PVC glue or solvents?
A.Class A (Water)B.Class B (Foam/Dry Chem)C.Class C (Electrical)D.Class D (Metal)✓B. Class B (Foam/Dry Chem)Explanation: Solvents and glues are flammable liquids, requiring a Class B extinguisher.
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Q5.When soldering copper pipe, you should always wear:
A.Safety glasses and glovesB.A welding helmetC.Rubber bootsD.A tie✓A. Safety glasses and glovesExplanation: Safety glasses protect eyes from flux splatter and solder; gloves protect against heat burns.
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Q6.Confined spaces (like manholes or septic tanks) require what before entry?
A.A permit and atmospheric testingB.Just a ladderC.A flashlightD.Holding your breath✓A. A permit and atmospheric testingExplanation: Permit-required confined spaces mandate air testing for oxygen deficiency or toxic gases before and during entry.
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Q7.Which gas is commonly found in sewers and is known as the 'silent killer' because it numbs the sense of smell?
A.MethaneB.Hydrogen Sulfide (H2S)C.Carbon MonoxideD.Oxygen✓B. Hydrogen Sulfide (H2S)Explanation: Hydrogen Sulfide (H2S) smells like rotten eggs at low concentrations but destroys the olfactory nerve at higher concentrations, making it undetectable and lethal.
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Q8.When cutting cast iron pipe with a snap cutter, the primary hazard is:
A.FireB.Flying metal shards/fragmentsC.ElectrocutionD.Toxic fumes✓B. Flying metal shards/fragmentsExplanation: Cast iron is brittle and can shatter or send chips flying when snapped. Eye protection is critical.
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Q9.A GFCI (Ground Fault Circuit Interrupter) is required for temporary power on job sites to prevent:
A.FireB.Electrocution (Shock)C.Tripping breakersD.Voltage drop✓B. Electrocution (Shock)Explanation: GFCIs detect ground faults and cut power instantly to prevent lethal shocks, especially in wet construction environments.
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Q10.Asbestos is most commonly found in older plumbing systems in:
A.Pipe insulationB.Copper pipe itselfC.SolderD.PVC glue✓A. Pipe insulationExplanation: Old steam and hot water pipes often used asbestos-containing insulation (lagging).
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Q11.When working on a gas line, you must:
A.Use a flame to check for leaksB.Shut off the gas supply and Lockout/TagoutC.Leave the gas onD.Use steel tools only✓B. Shut off the gas supply and Lockout/TagoutExplanation: Lockout/Tagout procedures ensure the gas cannot be accidentally turned on while work is being performed.
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Q12.The proper angle for setting up an extension ladder is a ratio of:
A.1 foot out for every 1 foot up (1:1)B.1 foot out for every 4 feet up (4:1)C.1 foot out for every 10 feet up (10:1)D.Vertical✓B. 1 foot out for every 4 feet up (4:1)Explanation: The 4:1 rule ensures stability. For every 4 feet of height, the base should be 1 foot away from the wall.
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Q13.Which of the following is considered 'Hot Work' requiring a permit in some facilities?
A.Gluing PVCB.Soldering or brazingC.Threading pipeD.Digging✓B. Soldering or brazingExplanation: Soldering involves open flame, constituting a fire hazard that often requires a Hot Work Permit.
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Q14.Lead-based solder was banned for potable water systems in what year (Safe Drinking Water Act amendment)?
A.1978B.1986C.1995D.2014✓B. 1986Explanation: The 1986 amendments to the Safe Drinking Water Act banned the use of lead solder (effective 1988).
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Q15.When lifting heavy pipes or water heaters, you should:
A.Bend at the waistB.Lift with your legs, keeping the back straightC.Twist while liftingD.Jerk the load upward✓B. Lift with your legs, keeping the back straightExplanation: Proper lifting technique prevents back injury.
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Q16.The top of a ladder must extend at least ___ feet above the landing surface.
A.2B.3C.4D.5✓B. 3Explanation: OSHA requires extension ladders to extend 3 feet above the landing to provide a handhold for getting off.
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Q17.What does MSDS (now SDS) stand for?
A.Material Safety Data SheetB.Maximum Safety Design StandardC.Mechanical System Design SheetD.Master Sewer Design Spec✓A. Material Safety Data SheetExplanation: Safety Data Sheets (SDS) provide detailed info on chemicals (like glue, flux, putty) used on site.
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Q18.Before digging a trench, you must call:
A.The inspectorB.811 (Call Before You Dig)C.The water companyD.The police✓B. 811 (Call Before You Dig)Explanation: 811 is the national number to request utility locates before excavation.
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Q19.When working with raw sewage, plumbers should ensure they have current vaccinations for:
A.FluB.Hepatitis B and TetanusC.Chicken PoxD.Malaria✓B. Hepatitis B and TetanusExplanation: Hepatitis B and Tetanus are significant risks when exposed to sewage and rusty metal/soil.
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Q20.Nominal pipe size refers to:
A.The exact outside diameterB.The exact inside diameterC.A standardized designation that approximates the inside diameterD.The wall thickness✓C. A standardized designation that approximates the inside diameterExplanation: Nominal size is a trade designation (e.g., 2 inch pipe), which approximates the ID but is not an exact measurement of OD or ID.
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