WCL Safety Standards & Regulations 5 — Questions and Answers
Question 1: In California, which agency issues the Welder Performance Qualification certification that is commonly required by Los Angeles area contractors?
- The certifying body specified by the applicable code (e.g., AWS, ASME) hired by the employer (Correct answer)
- California Department of Industrial Relations exclusively
- Los Angeles Bureau of Contract Administration
- OSHA Region 9
Correct answer: The certifying body specified by the applicable code (e.g., AWS, ASME) hired by the employer
Welder qualification is conducted per the applicable construction or manufacturing code (AWS D1.1, ASME Section IX, etc.) by a qualified employer or third-party testing agency, not a single state agency.
Question 2: What does a 'lockout/tagout' (LOTO) procedure protect against when maintenance welding is performed on machinery?
- Unexpected energization or startup of equipment during maintenance (Correct answer)
- Sparks igniting nearby materials
- Electrode contamination from machine oils
- Excessive current in the welding circuit
Correct answer: Unexpected energization or startup of equipment during maintenance
LOTO procedures (OSHA 1910.147) ensure equipment cannot be accidentally energized while welders perform maintenance work.
Question 3: Which type of respirator is required when welding stainless steel due to the hexavalent chromium (Cr VI) in the fumes?
- A half-face air-purifying respirator with P100 and OV/P100 combination cartridges, or a supplied-air respirator (Correct answer)
- A simple dust mask (N95) is sufficient
- No respirator is required if welding outdoors
- A full-face shield replaces respiratory protection
Correct answer: A half-face air-purifying respirator with P100 and OV/P100 combination cartridges, or a supplied-air respirator
Hexavalent chromium is a known carcinogen requiring P100 particulate filtration; supplied-air respirators may be needed at higher concentrations.
Question 4: According to OSHA's Hazard Communication Standard (HCS 2012), where must safety data sheets (SDS) for welding consumables be accessible to workers?
- In the work area or readily accessible to employees during their shift (Correct answer)
- Only in the main office building
- Posted on the company website only
- Distributed to employees annually by mail
Correct answer: In the work area or readily accessible to employees during their shift
OSHA HCS 2012 requires SDS to be readily accessible to employees during their shifts in their work area.
Question 5: When using oxy-fuel cutting equipment, which condition indicates a flashback and requires immediate equipment shutdown?
- A squealing or hissing sound in the torch with flame burning back into the hoses (Correct answer)
- Excessive tip spatter during cutting
- Low oxygen pressure at the regulator
- Difficulty lighting the torch
Correct answer: A squealing or hissing sound in the torch with flame burning back into the hoses
A squealing sound with the flame retreating into the hoses indicates flashback, a dangerous condition requiring immediate gas shutoff.
Question 6: Under Cal/OSHA Title 8 Section 5155, what is the permissible exposure limit (PEL) for ozone—a byproduct of welding arcs—as an 8-hour TWA?
- 0.1 ppm (Correct answer)
- 1.0 ppm
- 0.5 ppm
- 0.01 ppm
Correct answer: 0.1 ppm
Cal/OSHA sets the PEL for ozone at 0.1 ppm as an 8-hour time-weighted average, reflecting its toxicity to the respiratory system.
Question 7: A welder in Los Angeles is about to weld on structural steel in a building with active fire sprinklers. Per NFPA 51B, who must be notified and what must be done before hot work begins?
- The building owner and fire department must be notified, and sprinkler impairment procedures followed if sprinklers will be shut off (Correct answer)
- Only the immediate supervisor must be notified
- No notification is required because sprinklers provide automatic protection
- Only the insurance carrier must be notified
Correct answer: The building owner and fire department must be notified, and sprinkler impairment procedures followed if sprinklers will be shut off
NFPA 51B requires notification of the building owner and the fire department when sprinklers may be impaired, with proper impairment control procedures followed.
WCL Safety Standards & Regulations 5
In California, which agency issues the Welder Performance Qualification certification that is commonly required by Los Angeles area contractors?