Welding Certification — Knowledge Practice
Safety: practice questions
Our Welding Knowledge bank has 18 questions on this topic. Here are 5 of them with answers; the full mock exam draws from every topic, like the real one.
Question 1
What is the maximum safe working pressure for acetylene?
- 5 psig
- 50 psig
- 100 psig
- 15 psig
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D. 15 psig — Above 15 psig, acetylene can become unstable.
Question 2
What is metal fume fever usually caused by?
- Using a low-hydrogen rod
- Welding in cold weather
- Breathing fumes from welding galvanised (zinc-coated) steel
- Welding aluminium in a closed booth with argon as the shielding gas
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C. Breathing fumes from welding galvanised (zinc-coated) steel — Use ventilation and respiratory protection.
Question 3
What is the hazard of welding in a confined space?
- Fumes, oxygen deficiency or enrichment, and fire
- The welds are smaller
- There is no special hazard if the welder wears a helmet
- The space is too quiet
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A. Fumes, oxygen deficiency or enrichment, and fire — Confined spaces need permits, ventilation and monitoring.
Question 4
What hazard does welding near chlorinated solvents create?
- The solvent improves the weld by cleaning off oil and mill scale as you weld
- UV light can turn solvent vapours into toxic phosgene gas
- No hazard
- It increases spatter
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B. UV light can turn solvent vapours into toxic phosgene gas — Keep degreasing operations away from arcs.
Question 5
Why should welders wear safety glasses under their helmet?
- For style
- To see the arc better
- To protect eyes from flying debris and slag when the helmet is raised
- To reduce UV exposure more than the filter lens does when the helmet is down
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C. To protect eyes from flying debris and slag when the helmet is raised — Chipping and grinding produce flying particles.