Pipe Welding & Fabrication
Certification Practice Exam (2026
Edition)||| questions and answers with
rationales/graded A+/2026
update/100% correct /instant
download
Total Questions: 85
Passing Score: 75% (64 correct)
Time Allowed: 120 minutes
Standards Referenced: AWS D10.10, ASME BPVC Sec. IX, API 1104
Section 1: Safety & Shop Practices (Questions 1–12)
1. What is the minimum recommended oxygen level for safe welding in a confined
space?
• A) 15.5%
• B) 19.5%
• C) 21.0%
• D) 23.5%
Rationale: OSHA requires 19.5–23.5% O₂. Below 19.5% is oxygen-deficient,
risking asphyxiation.
2. Which fume is most hazardous when welding stainless steel pipe?
• A) Iron oxide
• B) Hexavalent chromium
• C) Manganese
, • D) Carbon dioxide
Rationale: Stainless steel contains chromium; welding produces Cr(VI), a
carcinogen requiring local exhaust ventilation.
3. When pipe welding in a vertical position, the proper fire watch duration after
welding ceases is:
• A) 15 minutes
• B) 30 minutes
• C) 1 hour
• D) No fire watch needed
Rationale: AWS safety standards mandate 30 min fire watch post-welding in high-
risk areas.
4. The maximum safe working pressure for a damaged acetylene hose is:
• A) 5 psi
• B) 15 psi
• C) 30 psi
• D) Not permitted
Rationale: Acetylene becomes unstable above 15 psi; damaged hoses must be
removed from service immediately.
5. What type of respirator is minimal for welding galvanized pipe?
• A) Dust mask
• B) P100 respirator
• C) N95 mask
• D) Half-mask with organic vapor cartridges
Rationale: Zinc oxide fumes require P100 particulate filtration; organic cartridges
are for solvents.
6. Which grounding practice is unsafe for pipe welding?
• A) Clamp to the pipe near weld
Certification Practice Exam (2026
Edition)||| questions and answers with
rationales/graded A+/2026
update/100% correct /instant
download
Total Questions: 85
Passing Score: 75% (64 correct)
Time Allowed: 120 minutes
Standards Referenced: AWS D10.10, ASME BPVC Sec. IX, API 1104
Section 1: Safety & Shop Practices (Questions 1–12)
1. What is the minimum recommended oxygen level for safe welding in a confined
space?
• A) 15.5%
• B) 19.5%
• C) 21.0%
• D) 23.5%
Rationale: OSHA requires 19.5–23.5% O₂. Below 19.5% is oxygen-deficient,
risking asphyxiation.
2. Which fume is most hazardous when welding stainless steel pipe?
• A) Iron oxide
• B) Hexavalent chromium
• C) Manganese
, • D) Carbon dioxide
Rationale: Stainless steel contains chromium; welding produces Cr(VI), a
carcinogen requiring local exhaust ventilation.
3. When pipe welding in a vertical position, the proper fire watch duration after
welding ceases is:
• A) 15 minutes
• B) 30 minutes
• C) 1 hour
• D) No fire watch needed
Rationale: AWS safety standards mandate 30 min fire watch post-welding in high-
risk areas.
4. The maximum safe working pressure for a damaged acetylene hose is:
• A) 5 psi
• B) 15 psi
• C) 30 psi
• D) Not permitted
Rationale: Acetylene becomes unstable above 15 psi; damaged hoses must be
removed from service immediately.
5. What type of respirator is minimal for welding galvanized pipe?
• A) Dust mask
• B) P100 respirator
• C) N95 mask
• D) Half-mask with organic vapor cartridges
Rationale: Zinc oxide fumes require P100 particulate filtration; organic cartridges
are for solvents.
6. Which grounding practice is unsafe for pipe welding?
• A) Clamp to the pipe near weld
