OIT Practice and Application 2 — Questions and Answers
Question 1: When performing a lockout/tagout procedure on a piece of industrial equipment, what is the correct first step?
- Apply the lock to the energy source
- Notify affected workers
- Identify all energy sources (Correct answer)
- Test the equipment to confirm de-energization
Correct answer: Identify all energy sources
The first step in lockout/tagout is to identify all energy sources associated with the equipment before any other action.
Question 2: A machinist measures a shaft diameter with a micrometer and gets a reading of 25.37 mm. The blueprint specifies 25.40 mm ± 0.03 mm. Is the part acceptable?
- Yes, it is within tolerance (Correct answer)
- No, it is undersize by 0.03 mm
- No, it exceeds the lower tolerance limit
- Yes, but it must be re-measured
Correct answer: Yes, it is within tolerance
The acceptable range is 25.37 mm to 25.43 mm, so 25.37 mm falls exactly on the lower limit and is acceptable.
Question 3: Under Ontario's Occupational Health and Safety Act, who has the primary duty to ensure a safe workplace?
- The joint health and safety committee
- The employer (Correct answer)
- The Ministry of Labour inspector
- The union representative
Correct answer: The employer
Under the OHSA, the employer bears the primary duty to ensure the workplace is safe and that all safety requirements are met.
Question 4: What type of fire extinguisher is appropriate for a Class C (electrical) fire in an industrial setting?
- Water-based extinguisher
- CO2 or dry chemical extinguisher (Correct answer)
- Foam extinguisher
- Wet chemical extinguisher
Correct answer: CO2 or dry chemical extinguisher
CO2 and dry chemical extinguishers are non-conductive and appropriate for Class C electrical fires, while water-based or foam agents conduct electricity.
Question 5: A welder notices a crack forming in a structural weld during inspection. What is the correct immediate action?
- Continue welding over the crack to fill it
- Report and tag the component out of service (Correct answer)
- Grind the crack smooth and leave it
- Apply weld repair without documentation
Correct answer: Report and tag the component out of service
A cracked structural weld must be reported and the component taken out of service until a proper repair procedure is authorized and performed.
Question 6: When reading an isometric piping drawing, what does a dashed line typically represent?
- A pipe running behind or hidden from view (Correct answer)
- A high-pressure pipe section
- A pipe requiring insulation
- A future installation line
Correct answer: A pipe running behind or hidden from view
Dashed lines in isometric drawings represent hidden lines — pipes or components that are behind other elements and not directly visible.
Question 7: A journeyperson electrician is installing conduit and needs to make a 90° bend. The conduit has a take-up of 150 mm. Where should the bender be placed?
- At the exact location of the desired bend
- 150 mm before the desired bend location (Correct answer)
- 150 mm after the desired bend location
- At the center of the conduit length
Correct answer: 150 mm before the desired bend location
The bender must be placed the take-up distance (150 mm) before the desired bend mark to account for the arc formed during bending.
OIT Practice and Application 2
When performing a lockout/tagout procedure on a piece of industrial equipment, what is the correct first step?