Millwright Alberta Period 3 Final
Exam Practice Questions with
Answers & Rationale
## SECTION 1: SAFETY, WHMIS, AND FIRE PROTECTION (Questions 1-
40)
**1. What are the four classes of fire extinguishers and their uses?**
**ANSWER:** Class A - Wood, paper, ordinary combustibles; Class B -
Flammable liquids; Class C - Electrical fires; Class D - Combustible
metals
**Rationale:** Fire extinguishers are classified by the type of fire they
are designed to extinguish. Using the wrong type can be ineffective or
dangerous.
**2. When is a WHMIS label not required?**
**ANSWER:** When a controlled product is used immediately
,**Rationale:** WHMIS labeling requirements apply to products that
are stored or transported. Products used immediately upon receipt may
be exempt from full labeling.
**3. What is the most effective type of hearing protection?**
**ANSWER:** Plugs and earmuffs (used together)
**Rationale:** Double hearing protection provides the highest level of
noise attenuation and is recommended in high-noise environments.
**4. What is the highest safest step on a ladder?**
**ANSWER:** Do not use the top 2 rungs
**Rationale:** Using the top rungs creates instability and increases the
risk of falling. The top two rungs are not designed to support a worker's
weight.
**5. What is the name of the scaffold cross brace?**
**ANSWER:** End or transverse brace
**Rationale:** Cross braces provide stability to scaffolding structures
by preventing lateral movement.
**6. What are the two main categories of screw compressors?**
,**ANSWER:** Oil wet and oil free dry screw compressors
**Rationale:** Screw compressors are classified based on whether
they use oil for sealing, cooling, and lubrication.
**7. Which rotor is the driver on a screw compressor?**
**ANSWER:** The male rotor
**Rationale:** The male rotor drives the female rotor in a screw
compressor through their meshing lobes.
**8. What determines the capacity of a screw compressor?**
**ANSWER:** Rotor length, diameter, lobe flute design, and speed
**Rationale:** These factors determine how much air or gas the
compressor can move per revolution.
**9. What is the primary purpose of a bearing?**
**ANSWER:** To support a load and reduce friction between rotating
and stationary components
**Rationale:** Bearings allow smooth rotation while supporting radial
and thrust loads.
, **10. What are the two main types of rolling element bearings?**
**ANSWER:** Ball bearings and roller bearings
**Rationale:** The rolling elements can be balls or various roller
shapes (cylindrical, tapered, spherical).
**11. What is a key difference between a Conrad-type deep-groove ball
bearing and a maximum-capacity bearing?**
**ANSWER:** A Conrad bearing has balls inserted between races
limiting the number; maximum-capacity bearings have a filling notch
allowing more balls, increasing radial load capacity
**Rationale:** The filling notch in maximum-capacity bearings allows
more balls to be inserted but reduces the bearing's ability to handle
thrust loads.
**12. When would you select a spherical roller bearing over a
cylindrical roller bearing?**
**ANSWER:** When you need to accommodate significant shaft
misalignment, as spherical roller bearings are self-aligning
**Rationale:** Spherical roller bearings can accommodate angular
misalignment between shaft and housing.
Exam Practice Questions with
Answers & Rationale
## SECTION 1: SAFETY, WHMIS, AND FIRE PROTECTION (Questions 1-
40)
**1. What are the four classes of fire extinguishers and their uses?**
**ANSWER:** Class A - Wood, paper, ordinary combustibles; Class B -
Flammable liquids; Class C - Electrical fires; Class D - Combustible
metals
**Rationale:** Fire extinguishers are classified by the type of fire they
are designed to extinguish. Using the wrong type can be ineffective or
dangerous.
**2. When is a WHMIS label not required?**
**ANSWER:** When a controlled product is used immediately
,**Rationale:** WHMIS labeling requirements apply to products that
are stored or transported. Products used immediately upon receipt may
be exempt from full labeling.
**3. What is the most effective type of hearing protection?**
**ANSWER:** Plugs and earmuffs (used together)
**Rationale:** Double hearing protection provides the highest level of
noise attenuation and is recommended in high-noise environments.
**4. What is the highest safest step on a ladder?**
**ANSWER:** Do not use the top 2 rungs
**Rationale:** Using the top rungs creates instability and increases the
risk of falling. The top two rungs are not designed to support a worker's
weight.
**5. What is the name of the scaffold cross brace?**
**ANSWER:** End or transverse brace
**Rationale:** Cross braces provide stability to scaffolding structures
by preventing lateral movement.
**6. What are the two main categories of screw compressors?**
,**ANSWER:** Oil wet and oil free dry screw compressors
**Rationale:** Screw compressors are classified based on whether
they use oil for sealing, cooling, and lubrication.
**7. Which rotor is the driver on a screw compressor?**
**ANSWER:** The male rotor
**Rationale:** The male rotor drives the female rotor in a screw
compressor through their meshing lobes.
**8. What determines the capacity of a screw compressor?**
**ANSWER:** Rotor length, diameter, lobe flute design, and speed
**Rationale:** These factors determine how much air or gas the
compressor can move per revolution.
**9. What is the primary purpose of a bearing?**
**ANSWER:** To support a load and reduce friction between rotating
and stationary components
**Rationale:** Bearings allow smooth rotation while supporting radial
and thrust loads.
, **10. What are the two main types of rolling element bearings?**
**ANSWER:** Ball bearings and roller bearings
**Rationale:** The rolling elements can be balls or various roller
shapes (cylindrical, tapered, spherical).
**11. What is a key difference between a Conrad-type deep-groove ball
bearing and a maximum-capacity bearing?**
**ANSWER:** A Conrad bearing has balls inserted between races
limiting the number; maximum-capacity bearings have a filling notch
allowing more balls, increasing radial load capacity
**Rationale:** The filling notch in maximum-capacity bearings allows
more balls to be inserted but reduces the bearing's ability to handle
thrust loads.
**12. When would you select a spherical roller bearing over a
cylindrical roller bearing?**
**ANSWER:** When you need to accommodate significant shaft
misalignment, as spherical roller bearings are self-aligning
**Rationale:** Spherical roller bearings can accommodate angular
misalignment between shaft and housing.
