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CWS (Other exams) practice questions

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Question 1Welding Safety & Quality

Before arc welding begins in a confined space, which practice best controls the risk of an oxygen-deficient atmosphere?

  1. Using a paper dust mask to filter the air
  2. Opening the space only after the welder feels lightheaded
  3. Relying on the welder's sense of smell to detect stale air
  4. Testing the atmosphere with a calibrated gas monitor before entry and continuously during work Correct answer.

Explanation

Confined spaces can accumulate shielding gases and displace oxygen without any warning odor, so atmospheric testing with a calibrated monitor before entry and continuous monitoring during the work is the accepted control. Personal senses cannot reliably detect oxygen deficiency, and dust masks do not supply or filter oxygen.

Question 2Welding Safety & Quality

What is the primary purpose of a welding helmet's filter shade number?

  1. To measure the amperage flowing through the electrode
  2. To control the amount of visible, ultraviolet, and infrared radiation reaching the eyes Correct answer.
  3. To indicate the arc voltage to the operator
  4. To filter toxic fumes from the breathing zone

Explanation

The shade number specifies the darkness of the filter and therefore how much optical radiation, including UV and IR, reaches the eyes. Selecting an appropriate shade for the process and current protects against arc eye and long-term eye damage.

Question 3Welding Safety & Quality

Which document typically specifies the welding procedure, base materials, filler metal, and acceptance criteria for a welded joint on a construction project?

  1. The welder's pay stub
  2. The material safety data sheet for the filler metal
  3. The equipment calibration sticker
  4. The welding procedure specification referenced by the contract drawings Correct answer.

Explanation

The welding procedure specification, together with the applicable code and the contract documents, defines how the joint is to be made and what inspection acceptance criteria apply. Safety data sheets and calibration records serve different purposes.

Question 4Welding Safety & Quality

Hot work permits are required primarily because they:

  1. Replace the need for a fire watch during welding
  2. Guarantee that no sparks will escape the work area
  3. Formally authorize work after fire hazards have been assessed and controls put in place Correct answer.
  4. Certify the welder's skill qualification

Explanation

A hot work permit documents that fire hazards were evaluated and that precautions such as removing combustibles, shielding, and a fire watch are established before work starts. It does not eliminate the need for a fire watch or certify welder skill.

Question 5Welding Safety & Quality

Which personal protective equipment is essential when chipping slag from a completed weld?

  1. A respirator with acid-gas cartridges
  2. Safety glasses with side shields or goggles Correct answer.
  3. Insulated rubber gloves rated for line voltage
  4. Hearing protection alone

Explanation

Chipping slag produces flying fragments, so eye protection with side coverage or goggles is required. Other PPE may be needed for specific hazards, but impact protection for the eyes is the direct control.

Question 6Welding Safety & Quality

A welder notices the work lead clamp is loose and the connection is heating up. What is the correct action?

  1. Move the clamp to a painted surface to improve contact
  2. Continue welding but reduce the amperage slightly
  3. Stop welding and repair or replace the connection before continuing Correct answer.
  4. Wrap the connection in electrical tape and keep welding

Explanation

A loose work lead connection creates resistance heating and can cause arcing, fire, or shock hazards, so work should stop until the connection is repaired. Continuing with reduced current or improvised tape does not correct the underlying defect.

Question 7Welding Safety & Quality

Which statement correctly describes the role of a fire watch during welding operations?

  1. The fire watch monitors for sparks and smoldering fires and has extinguishing equipment ready Correct answer.
  2. The fire watch adjusts the welding current for better penetration
  3. The fire watch signs off on the final weld inspection
  4. The fire watch performs the root pass while the welder rests

Explanation

A fire watch is stationed to detect ignition from sparks and slag and to respond immediately with firefighting equipment. The role is fire prevention, not welding or inspection.

Question 8Welding Safety & Quality

Why should welding cables be kept off wet floors and away from sharp edges?

  1. To prevent insulation damage and electrical shock hazards Correct answer.
  2. To keep the cable from getting too cold
  3. To reduce the amount of shielding gas used
  4. To improve the weld bead appearance

Explanation

Wet floors increase the chance of a grounded path through the welder, and sharp edges can cut insulation and expose live conductors. Both conditions raise the risk of electric shock, so routing and inspection of cables matter.

Question 9Welding Safety & Quality

A welder is qualified on 10 mm plate with a given process and position. Which additional variable most commonly requires a new qualification test?

  1. Changing the work shift schedule
  2. Changing the color of the welding helmet
  3. Changing the brand of chipping hammer
  4. Changing from the qualified welding position to a different position Correct answer.

Explanation

Welder qualification is tied to essential variables that include process, position, thickness range, and filler classification. A change in welding position is a typical essential variable that requires requalification.

Question 10Welding Safety & Quality

Which condition most directly indicates that a welding procedure may need requalification?

  1. The welder changes gloves
  2. The weld is made on a different day of the week
  3. The base metal specification is changed to a different material group Correct answer.
  4. The welding machine is moved to another bay

Explanation

A change in base metal group is an essential variable in most welding procedure specifications and generally requires requalification. Location, PPE, and scheduling do not alter the metallurgical basis of the procedure.

Question 11Welding Safety & Quality

A welder finds porosity clustered at the start of a fillet weld. Which cause is most likely?

  1. A weld longer than specified
  2. Excessive travel speed at the end of the weld
  3. A higher-than-required preheat
  4. Insufficient gas coverage or a contaminated start at arc initiation Correct answer.

Explanation

Porosity at the start often results from poor shielding during arc initiation or contamination such as moisture, oil, or rust at the start point. Travel speed at the end and overall weld length affect other features, not start porosity.

Question 12Welding Safety & Quality

Which inspection method is best suited to detecting surface-breaking discontinuities on a ferromagnetic weld?

  1. Magnetic particle testing Correct answer.
  2. Tensile testing
  3. Radiographic testing
  4. Ultrasonic testing of internal flaws only

Explanation

Magnetic particle testing detects surface and near-surface discontinuities in ferromagnetic materials by revealing flux leakage. Radiography and ultrasonography are aimed at internal flaws, and tensile testing is destructive.

Question 13Welding Safety & Quality

Why is preheat used before welding thick-section carbon steel?

  1. To reduce the shielding gas flow requirement
  2. To increase the deposition rate of the electrode
  3. To slow the cooling rate and reduce the risk of hydrogen-assisted cracking Correct answer.
  4. To eliminate the need for post-weld inspection

Explanation

Preheat raises the base metal temperature so the weld cools more slowly, which helps hydrogen escape and reduces hardening and cracking risk. It does not replace inspection or change shielding gas needs.

Question 14Welding Safety & Quality

A weld shows a linear indication running along the toe of the weld. Which defect type should be suspected first?

  1. A toe crack Correct answer.
  2. Gas porosity
  3. Slag inclusion
  4. Lack of fusion at the root

Explanation

A linear indication along the weld toe is characteristic of a toe crack, which often initiates from stress concentration and hydrogen. Porosity appears as rounded indications, and root lack of fusion is located at the joint root.

Question 15Welding Safety & Quality

What is the main quality concern when welding is performed with a damp electrode or wet flux?

  1. Increased arc voltage readings
  2. Reduced weld length
  3. Hydrogen pickup that can lead to cracking Correct answer.
  4. Higher travel speed

Explanation

Moisture in electrodes or flux is a source of hydrogen, which can diffuse into the weld and cause hydrogen-assisted cracking. Electrodes and flux must be stored and dried according to the manufacturer's requirements.

Question 16Welding Safety & Quality

Which practice best protects a welder from fume exposure when welding galvanized steel?

  1. Welding faster to reduce the time in the plume
  2. Standing directly over the arc to keep the plume low
  3. Holding the breath while the arc is on
  4. Local exhaust ventilation at the arc plus appropriate respiratory protection Correct answer.

Explanation

Galvanized coatings produce metal fume that can cause metal fume fever, so source capture with local exhaust ventilation and suitable respiratory protection is the primary control. Positioning over the arc increases exposure rather than reducing it.

Question 17Welding Safety & Quality

A weld cap is specified to be flush with the base metal, but the cap is 2 mm high. How should this be recorded?

  1. As a cosmetic issue with no documentation
  2. As acceptable because reinforcement always improves strength
  3. As a nonconformance against the specified weld profile Correct answer.
  4. As a defect only if the weld is painted

Explanation

Excess reinforcement beyond the specified profile is a dimensional nonconformance and should be documented and dispositioned per the applicable code. Reinforcement is not automatically beneficial, and cosmetic appearance does not override the specification.

Question 18Welding Safety & Quality

Which factor most influences the choice of shade number for gas tungsten arc welding at low current?

  1. The diameter of the filler rod
  2. The length of the work lead
  3. The thickness of the base metal
  4. The welding current level and the resulting arc intensity Correct answer.

Explanation

Shade selection tables are based primarily on the welding process and current, because current determines arc intensity and radiation output. Base metal thickness and lead length do not drive eye protection shade choice.

Question 19Welding Safety & Quality

During a visual inspection, a welder observes undercut along the edge of a fillet weld. Which consequence makes undercut a quality concern?

  1. It increases the weld's resistance to fatigue
  2. It improves the weld's appearance without affecting strength
  3. It reduces the throat thickness and creates a stress concentration Correct answer.
  4. It raises the preheat requirement

Explanation

Undercut removes base metal at the weld toe, reducing the effective throat and creating a notch that concentrates stress. Limits on undercut depth are specified because of these effects on strength and fatigue life.

Question 20Welding Safety & Quality

A welder must perform work in a tank that previously held flammable liquid. Which step is required before hot work may begin?

  1. The tank must be painted inside to seal residual vapors
  2. The tank must be filled with water to the top and left filled
  3. The tank must be cleaned, purged, and tested to confirm it is free of flammable atmosphere Correct answer.
  4. The welder must wear a dust mask and proceed

Explanation

Tanks that held flammable liquids must be cleaned and purged and then tested to verify the absence of a flammable atmosphere before hot work. Painting or partial measures do not remove the explosion hazard.

Question 21Welding Safety & Quality

Which statement best explains why welding machine frames and workpieces should be properly grounded?

  1. Grounding increases the welding current available at the arc
  2. Grounding prevents the electrode from sticking
  3. A low-resistance path to earth limits voltage differences that could drive current through the operator Correct answer.
  4. Grounding eliminates the need for insulated electrode holders

Explanation

Grounding provides a low-resistance path so fault current is directed safely to earth rather than through a person. It does not increase welding current or remove the need for insulated holders.

Question 22Welding Safety & Quality

A procedure specifies a maximum interpass temperature of 250 degrees Celsius. A welder measures 285 degrees Celsius before the next pass. What is the correct response?

  1. Pause and allow the weld to cool to within the specified limit before continuing Correct answer.
  2. Continue welding because interpass temperature only affects appearance
  3. Increase the current to compensate for the higher temperature
  4. Add a second welder to finish faster

Explanation

Interpass temperature is an essential variable that affects mechanical properties and cracking risk, so welding must wait until the temperature falls within the specified maximum. Exceeding the limit without authorization is a procedure violation.

Question 23Welding Safety & Quality

A welder qualified under a procedure using a cellulosic electrode is asked to weld with a low-hydrogen electrode on the same joint. What is the key qualification issue?

  1. Nothing changes because both electrodes are covered
  2. Only the welder's glove size needs review
  3. The change in filler metal classification is an essential variable requiring requalification Correct answer.
  4. The change is acceptable if the weld is painted afterward

Explanation

Filler metal classification is an essential variable in welder and procedure qualification because it changes hydrogen content, mechanical properties, and operating characteristics. Substituting a different classification without qualification is not permitted.

Question 24Welding Safety & Quality

Radiography of a butt weld reveals a rounded dark indication near the weld centerline with sharp edges on the film. Which interpretation is most appropriate?

  1. The indication should be evaluated against the acceptance criteria because its nature and size determine acceptability Correct answer.
  2. It proves the base metal is incorrect
  3. It is acceptable because rounded indications never matter
  4. It is automatically a crack because it appears dark

Explanation

Radiographic indications must be characterized by type, size, and distribution and then judged against the applicable acceptance criteria. Darkness alone does not identify the defect, and rounded indications are not automatically acceptable.

Question 25Welding Safety & Quality

A fabricator wants to reduce hydrogen cracking risk on a high-strength steel joint. Which combination of controls is most technically sound?

  1. Weld in a cold draft to speed cooling
  2. Follow the qualified preheat and interpass limits, use properly dried low-hydrogen consumables, and control cooling Correct answer.
  3. Use any available electrode and rely on visual inspection afterward
  4. Increase travel speed and skip preheat to save time

Explanation

Hydrogen cracking is controlled by limiting hydrogen sources, using adequate preheat, and managing cooling and interpass temperature per the qualified procedure. Skipping controls or accelerating cooling increases susceptibility.

Question 26Welding Safety & Quality

Which type of eye protection is specifically required when chipping slag from a completed weld?

  1. Sunglasses with UV protection
  2. Face shield over safety glasses Correct answer.
  3. Clear safety glasses with side shields
  4. Tinted welding goggles with a filter lens

Explanation

Chipping slag produces flying fragments that can injure the eyes and face; a face shield worn over safety glasses provides the necessary impact protection. Tinted welding goggles are for arc viewing, not chipping, and sunglasses offer no impact resistance.

Question 27Welding Safety & Quality

When welding in a confined space, which atmospheric condition must be verified before entry and maintained during the work?

  1. Relative humidity below 60%
  2. Oxygen content above 23.5%
  3. Oxygen content between 19.5% and 23.5% Correct answer.
  4. Carbon dioxide level below 5%

Explanation

Confined spaces must be tested for oxygen, flammables, and toxics before entry; the acceptable oxygen range is 19.5% to 23.5% by volume. Oxygen above 23.5% creates a fire hazard, and the other parameters are not the primary entry criteria.

Question 28Welding Safety & Quality

What is the primary purpose of a welding machine's disconnect switch?

  1. To provide a means to completely de-energize the machine for maintenance Correct answer.
  2. To protect the electrode holder from overload
  3. To change the welding polarity
  4. To adjust welding current remotely

Explanation

The disconnect switch isolates the welding machine from its power source so that maintenance or repair can be performed safely. It is not used for current adjustment, polarity change, or electrode holder protection.

Question 29Welding Safety & Quality

Which statement correctly describes the required condition of welding cables before use?

  1. Cables must be inspected for damage and repaired or replaced if insulation is compromised Correct answer.
  2. Cables can be run through doorways if protected by a mat
  3. Cables may be coiled around the welder's body to keep them off the floor
  4. Cables may be spliced with tape if the splice is insulated

Explanation

Welding cables must be inspected before each use; damaged insulation exposes the welder to shock and must be repaired or the cable replaced. Taping splices, running through doorways, and coiling around the body all create hazards.

Question 30Welding Safety & Quality

Which fire prevention measure is required in the area where welding or cutting is performed?

  1. Closing all doors and windows to contain sparks
  2. Posting a sign that welding is in progress
  3. Wetting the floor around the work area
  4. Removing all combustible materials within 35 feet (11 m) or guarding them against ignition Correct answer.

Explanation

Hot work requires that combustible materials be removed from the area or protected by fire-resistant guards or curtains. Wetting the floor, posting signs, or closing openings does not address the ignition hazard.

Question 31Welding Safety & Quality

Which statement best describes the function of a welding procedure specification (WPS)?

  1. It specifies the inspection acceptance criteria only
  2. It lists the welder's qualifications and certifications
  3. It records the results of non-destructive testing
  4. It provides the required variables and ranges for making a production weld Correct answer.

Explanation

A WPS is a written document that specifies the welding variables-such as process, filler metal, current, and preheat-needed to produce a weld that meets the required quality. It is not a qualification record, test report, or acceptance standard.

Question 32Welding Safety & Quality

Which type of weld joint is formed when two members are placed end to end in the same plane?

  1. Corner joint
  2. Butt joint Correct answer.
  3. Tee joint
  4. Lap joint

Explanation

A butt joint joins two members end to end in the same plane. A tee joint is perpendicular, a lap joint overlaps, and a corner joint meets at an angle.

Question 33Welding Safety & Quality

What is the primary hazard associated with welding on a workpiece that is not properly grounded?

  1. The weld may be contaminated with slag
  2. The workpiece may become magnetized and deflect the arc
  3. The welder may become part of the electrical circuit and receive a shock Correct answer.
  4. The welding arc may become unstable and spatter excessively

Explanation

If the workpiece is not grounded, the welding current may seek an alternate path through the welder, causing a potentially fatal shock. Poor grounding does not directly cause slag contamination, arc instability, or arc blow.

Question 34Welding Safety & Quality

Which action is required before performing hot work on a tank that previously contained a flammable liquid?

  1. Purge the tank with oxygen to remove fumes
  2. Open all hatches and begin welding from the top
  3. Fill the tank with water and weld immediately
  4. Obtain a hot work permit and verify the tank has been cleaned and tested for flammables Correct answer.

Explanation

Hot work on tanks that held flammables requires cleaning, inerting or purging, atmospheric testing, and a hot work permit. Filling with water may be part of preparation but welding immediately is unsafe, and purging with oxygen creates an extreme fire hazard.

Question 35Welding Safety & Quality

A welder is using a 5 kW engine-driven welding machine in an enclosed area. Which control is most critical to prevent carbon monoxide exposure?

  1. Increasing the welding current to reduce engine load
  2. Opening a window slightly
  3. Wearing a respirator with particulate filters
  4. Routing the engine exhaust outside the work area Correct answer.

Explanation

Engine-driven welders produce carbon monoxide, an odorless and deadly gas; the exhaust must be routed outdoors or the area must be ventilated with mechanical air changes. Particulate respirators do not remove CO, and a slightly open window is insufficient.

Question 36Welding Safety & Quality

A welder is welding in a position that requires the electrode holder to be held above shoulder height for extended periods. Which ergonomic control is most appropriate?

  1. Use a lighter electrode holder and support the arm to reduce static load Correct answer.
  2. Weld with one hand while resting the other on the workpiece
  3. Increase the welding current to speed the work
  4. Take shorter, more frequent breaks without changing technique

Explanation

Overhead work creates static load on the shoulders and arms; using a lighter holder and supporting the arm reduces fatigue and musculoskeletal risk. Increasing current does not address posture, and resting a hand on the workpiece can cause shock.

Question 37Welding Safety & Quality

Which statement correctly describes the purpose of a fire watch during welding operations?

  1. To inspect the completed weld for defects
  2. To monitor the welder's technique and productivity
  3. To ensure that no fire starts and to extinguish incipient fires Correct answer.
  4. To control access to the welding area

Explanation

A fire watch is assigned to watch for sparks and smoldering fires during and after hot work, and to sound an alarm or extinguish a fire if one starts. The fire watch does not perform welding inspection or productivity monitoring.

Question 38Welding Safety & Quality

During visual inspection of a completed fillet weld, a welder measures the leg length as 6 mm where the drawing specifies 8 mm. Which action is correct?

  1. Accept the weld because the difference is within typical tolerance
  2. Add a cover pass without documentation
  3. Record the undersize weld as a defect and initiate repair per the quality plan Correct answer.
  4. Increase the welding current for the next weld

Explanation

A fillet weld that is undersize relative to the specified leg length does not meet the drawing requirement and must be documented and repaired according to the quality plan. Accepting it, adding an undocumented pass, or adjusting future current does not correct the nonconformance.

Question 39Welding Safety & Quality

Which condition is the most likely cause of a welder receiving a shock when touching the workpiece with bare hands while the electrode holder is energized?

  1. The welding machine is set to DCEN instead of DCEP
  2. The electrode is too large for the joint
  3. The welding cable is too short
  4. The workpiece is connected to the work lead but the welder is not insulated from it Correct answer.

Explanation

If the welder's body completes a circuit between the energized electrode and the workpiece, current can flow through the welder. Polarity, electrode size, and cable length do not by themselves cause shock in this scenario.

Question 40Welding Safety & Quality

Which statement best explains why welding fume should be controlled at the source rather than relying on general dilution ventilation?

  1. Source capture eliminates the need for personal protective equipment
  2. General ventilation increases the welding current requirement
  3. General ventilation is always prohibited in welding shops
  4. Source capture removes contaminants before they enter the breathing zone Correct answer.

Explanation

Local exhaust ventilation captures fume at the arc before it reaches the welder's breathing zone, which is more effective than diluting the entire workplace atmosphere. General ventilation is not prohibited, and PPE is still required as a backup.

Question 41Welding Safety & Quality

A welder is qualified to weld 10 mm plate in the 1G position with a specific process. Which change would most likely require requalification?

  1. Changing from 10 mm to 12 mm plate thickness
  2. Changing from a V-groove to a square-groove joint
  3. Changing the welding current within the qualified range
  4. Changing from the 1G to the 3G position Correct answer.

Explanation

Position is an essential variable in welder qualification; moving from flat (1G) to vertical (3G) typically requires a new qualification. Thickness changes within the qualified range, joint design changes not affecting essential variables, and current adjustments within range do not automatically require requalification.

Question 42Welding Safety & Quality

Which document typically records the actual welding parameters used during production for traceability?

  1. Welding procedure specification (WPS)
  2. Welding log or production record Correct answer.
  3. Procedure qualification record (PQR)
  4. Welder performance qualification (WPQ)

Explanation

A welding log or production record captures the actual parameters, welder, and date for each weld, providing traceability. The WPS specifies ranges, the PQR documents procedure qualification testing, and the WPQ documents welder qualification.

Question 43Welding Safety & Quality

A weld exhibits a cluster of small, rounded gas pockets near the surface. Which term best describes this condition?

  1. Porosity Correct answer.
  2. Lack of fusion
  3. Underfill
  4. Slag inclusion

Explanation

Porosity consists of gas pockets trapped in the weld metal, often appearing as rounded voids. Slag inclusion is solid nonmetallic material, lack of fusion is incomplete bonding, and underfill is a concave surface.

Question 44Welding Safety & Quality

Which non-destructive examination method uses a liquid penetrant to reveal surface-breaking defects?

  1. Magnetic particle testing
  2. Ultrasonic testing
  3. Penetrant testing Correct answer.
  4. Radiographic testing

Explanation

Penetrant testing applies a liquid that seeps into surface openings and is then drawn out by a developer, revealing defects. Radiography and ultrasonics detect internal flaws, and magnetic particle testing requires ferromagnetic materials.

Question 45Welding Safety & Quality

Which factor most directly determines the required preheat temperature for a given steel weldment?

  1. The carbon equivalent and thickness of the steel Correct answer.
  2. The ambient humidity
  3. The welding process used
  4. The welder's qualification level

Explanation

Preheat requirements are based primarily on the steel's hardenability (often expressed as carbon equivalent) and its thickness, which affect cooling rate and hydrogen cracking risk. Process, welder qualification, and humidity are secondary considerations.

Question 46Welding Safety & Quality

A welder is using a cellulosic electrode when the WPS specifies a low-hydrogen electrode. What is the most significant risk of proceeding with the cellulosic electrode?

  1. Hydrogen-induced cracking in the weld heat-affected zone Correct answer.
  2. Increased spatter and cleanup time
  3. Reduced travel speed and productivity
  4. Difficulty in striking the arc

Explanation

Cellulosic electrodes introduce hydrogen into the weld, and on susceptible steels this can lead to hydrogen-assisted cracking. Spatter, productivity, and arc starting are secondary concerns compared with cracking.

Question 47Welding Safety & Quality

During radiographic inspection, a dark, irregular indication with jagged edges appears along the weld centerline. Which type of discontinuity is most likely?

  1. Crack Correct answer.
  2. Porosity
  3. Lack of penetration
  4. Slag inclusion

Explanation

Cracks appear on radiographs as dark, irregular lines with sharp ends, often along the centerline. Porosity is rounded, slag is irregular but usually less linear, and lack of penetration is a straight line at the root.

Question 48Welding Safety & Quality

A welder is welding a high-strength steel and the interpass temperature exceeds the WPS maximum. Which consequence is most likely if welding continues?

  1. Reduced risk of hydrogen cracking
  2. Increased deposition efficiency
  3. Improved toughness due to slower cooling
  4. Loss of mechanical properties in the weld and heat-affected zone Correct answer.

Explanation

Exceeding the maximum interpass temperature can cause overheating, grain growth, and a loss of strength and toughness in the weld and heat-affected zone. It does not improve properties or reduce cracking risk.

Question 49Welding Safety & Quality

Which combination of controls best minimizes the risk of hydrogen cracking in a high-strength steel weldment?

  1. Increase welding current and travel speed
  2. Weld in a humid environment to improve arc stability
  3. Use low-hydrogen electrodes, preheat, and maintain interpass temperature Correct answer.
  4. Use cellulosic electrodes and increase cooling rate

Explanation

Hydrogen cracking is controlled by reducing hydrogen input (low-hydrogen electrodes), slowing cooling (preheat), and maintaining interpass temperature to allow hydrogen to escape. Cellulosic electrodes, fast cooling, and humidity increase risk.

Question 50Welding Safety & Quality

A welder is using a transformer-type welding machine and notices a slight tingling sensation when touching the workpiece. Which action should be taken first?

  1. Continue welding but wear thicker gloves
  2. Increase the welding current to stabilize the arc
  3. Reverse the electrode polarity
  4. Stop welding and have the machine inspected for electrical faults Correct answer.

Explanation

A tingling sensation indicates stray current or an electrical fault and is a serious shock hazard; welding must stop and the machine must be inspected by a qualified person. Thicker gloves, polarity changes, or current adjustments do not correct the fault.