AWS Safety & Welding Standards 2 — Questions and Answers
Question 1: According to AWS Z49.1, what is the minimum air change rate required in a confined space during welding?
- 2 air changes per hour
- 4 air changes per hour
- 6 air changes per hour (Correct answer)
- 10 air changes per hour
Correct answer: 6 air changes per hour
AWS Z49.1 requires a minimum of 6 air changes per hour in confined spaces to maintain safe ventilation during welding.
Question 2: What ANSI/AWS standard specifically addresses safety in welding, cutting, and allied processes?
- AWS D1.1
- AWS Z49.1 (Correct answer)
- AWS A5.1
- AWS B2.1
Correct answer: AWS Z49.1
AWS Z49.1 is the primary standard titled 'Safety in Welding, Cutting, and Allied Processes.'
Question 3: When welding on containers that held flammable materials, AWS standards require the welder to:
- Weld only on the exterior surface
- Fill the container with water or inert gas before welding (Correct answer)
- Use low-amperage settings only
- Apply fire-resistant coatings before welding
Correct answer: Fill the container with water or inert gas before welding
AWS Z49.1 mandates that containers previously holding flammables be purged with water or inert gas to eliminate explosion risk.
Question 4: Which eye protection shade is generally recommended for shielded metal arc welding (SMAW) at currents between 75–200 amps?
- Shade 8
- Shade 10 (Correct answer)
- Shade 12
- Shade 14
Correct answer: Shade 10
ANSI/AWS guidelines recommend shade 10 lens for SMAW operations in the 75–200 amp range.
Question 5: Under OSHA 1910.252, what is the maximum allowable iron oxide fume concentration in the welder's breathing zone?
- 1 mg/m³
- 5 mg/m³ (Correct answer)
- 10 mg/m³
- 15 mg/m³
Correct answer: 5 mg/m³
OSHA's permissible exposure limit (PEL) for iron oxide fume is 5 mg/m³ as an 8-hour time-weighted average.
Question 6: AWS D1.1 structural welding code defines a 'qualified welder' as one who has:
- Completed a vocational welding program
- Passed a performance qualification test per the code (Correct answer)
- Held a welding job for at least 2 years
- Obtained an AWS Certified Welder credential
Correct answer: Passed a performance qualification test per the code
AWS D1.1 defines qualification strictly through successful completion of prescribed performance tests documented by test records.
Question 7: Which of the following is a primary hazard associated with ozone gas generated during GMAW of aluminum?
- Skin burns from UV exposure
- Pulmonary edema from inhalation (Correct answer)
- Electric shock from ionized air
- Eye damage from infrared radiation
Correct answer: Pulmonary edema from inhalation
Ozone generated by UV arc radiation reacting with oxygen can cause pulmonary edema (fluid in the lungs) if inhaled in sufficient concentration.
AWS Safety & Welding Standards 2
According to AWS Z49.1, what is the minimum air change rate required in a confined space during welding?