NEVADA CONCRETE CONTRACTOR
C-5 LICENSE
PRACTICE EXAMINATION
,Nevada Concrete Contractor (C-5) — Practice Examination Page 2
SAFETY & OSHA REGULATIONS — Questions 1–35
Q1 What is OSHA's permissible exposure limit (PEL) for respirable crystalline silica in construction?
A) 0.025 mg/m³ as an 8-hr TWA
B) 0.05 mg/m³ as an 8-hr TWA
C) 0.5 mg/m³ as an 8-hr TWA
D) 2 mg/m³ as an 8-hr TWA
Answer: B) 0.05 mg/m³ as an 8-hr TWA
OSHA 29 CFR 1926.1153 sets the PEL at 0.05 mg/m³ as an 8-hour TWA, cutting the previous limit in half to reduce silicosis risk.
Q2 Which hazard is most associated with silica dust generated during concrete grinding?
A) Hearing loss
B) Respiratory disease including silicosis and lung cancer
C) Chemical skin burns
D) Eye strain
Answer: B) Respiratory disease including silicosis and lung cancer
Inhaling fine respirable crystalline silica particles can cause silicosis, a progressive, incurable lung disease, and raises risk of lung
cancer and COPD.
Q3 What is the correct method for lifting heavy concrete forms to prevent back injury?
A) Bend at the waist and pull with the back
B) Twist the torso while lifting
C) Keep the load close to the body and lift with the legs
D) Use only the shoulder muscles
Answer: C) Keep the load close to the body and lift with the legs
Proper lifting requires bending the knees, keeping the load close, and using leg muscles to lift — minimizing spinal stress.
Q4 When must lockout/tagout (LOTO) procedures be implemented on concrete equipment?
A) During routine cleaning only
B) Before starting a new shift
C) When maintenance or repair is being performed
D) Only when OSHA inspectors are present
Answer: C) When maintenance or repair is being performed
OSHA 29 CFR 1910.147 requires LOTO whenever servicing equipment where unexpected energization could injure workers.
Q5 At what minimum height must construction workers be protected by fall protection per OSHA?
A) 4 feet
B) 6 feet
C) 8 feet
D) 10 feet
Answer: B) 6 feet
OSHA 29 CFR 1926.502 requires fall protection at elevations of 6 feet or more above a lower level.
Original practice content for study purposes only. Always consult official NSCB materials and current code editions.
,Nevada Concrete Contractor (C-5) — Practice Examination Page 3
Q6 Wet concrete has an approximate pH of:
A) 6–7
B) 7–8
C) 9–10
D) 12–13
Answer: D) 12–13
Fresh concrete has a pH of 12–13 due to calcium hydroxide produced during cement hydration, causing severe alkali burns with
prolonged skin contact.
Q7 Before any worker enters a permit-required confined space, what must be done first?
A) Get written approval from the project manager
B) Test the atmosphere for oxygen, flammable gas, and toxic vapors
C) Ventilate for a minimum of 60 minutes
D) Notify local fire department
Answer: B) Test the atmosphere for oxygen, flammable gas, and toxic vapors
OSHA 29 CFR 1910.146 requires atmospheric testing before entry — verifying oxygen levels (19.5–23.5%), absence of flammable
gas, and toxic vapors.
Q8 What slope angle is required for Type C soil excavations per OSHA?
A) 90° (vertical)
B) 3/4H:1V
C) 1H:1V
D) 1.5H:1V
Answer: D) 1.5H:1V
OSHA Appendix B to Subpart P classifies Type C soil as requiring a 1.5H:1V (34°) maximum slope to prevent cave-in.
Q9 Spoil piles from an excavation must be placed at least how far from the edge?
A) 1 foot
B) 2 feet
C) 3 feet
D) 5 feet
Answer: B) 2 feet
OSHA 29 CFR 1926.651(j)(2) requires excavated material to be kept a minimum of 2 feet from the edge of any excavation.
Q10 Which PPE is required when using a jackhammer to break concrete?
A) Hard hat only
B) Safety glasses only
C) Hard hat, safety glasses, hearing protection, gloves, and steel-toed boots
D) A respirator only
Answer: C) Hard hat, safety glasses, hearing protection, gloves, and steel-toed boots
Jackhammer operation exposes workers to flying debris, extreme noise (>100 dB), vibration, and foot crush hazards — all listed
PPE is required.
Original practice content for study purposes only. Always consult official NSCB materials and current code editions.
, Nevada Concrete Contractor (C-5) — Practice Examination Page 4
Q11 What is the minimum distance a worker must maintain from an energized overhead power line?
A) 3 feet
B) 5 feet
C) 10 feet
D) 15 feet
Answer: C) 10 feet
OSHA 29 CFR 1926.1408 requires a minimum 10-foot clearance from energized power lines up to 50 kV.
Q12 An SDS for cement must include how many standardized sections per OSHA's Hazard
Communication Standard?
A) 8
B) 12
C) 16
D) 20
Answer: C) 16
OSHA's revised HazCom Standard (29 CFR 1910.1200) requires SDS documents to follow GHS format with exactly 16
standardized sections.
Q13 What type of ladder must extend at least 3 feet above the upper landing surface?
A) Step ladder
B) Extension ladder or job-built ladder
C) Articulating ladder
D) Platform ladder
Answer: B) Extension ladder or job-built ladder
OSHA 29 CFR 1926.1053(b)(1) requires portable ladders to extend at least 3 feet above the upper landing to provide a safe
handhold.
Q14 Hand-arm vibration syndrome (HAVS) from concrete vibrators is a disorder affecting:
A) The cardiovascular system
B) The blood vessels, nerves, and muscles of the hand and arm
C) The respiratory system
D) The auditory system
Answer: B) The blood vessels, nerves, and muscles of the hand and arm
HAVS results from prolonged vibrating tool use, damaging blood vessels and nerves, causing tingling, numbness, and loss of grip
strength.
Q15 Under OSHA's Heat Illness Prevention standard, which is NOT one of the three key prevention
elements?
A) Water
B) Rest
C) Shade
D) Sunscreen
Answer: D) Sunscreen
OSHA's heat illness prevention focuses on three elements: Water, Rest, and Shade. Sunscreen is not part of the official
framework.
Original practice content for study purposes only. Always consult official NSCB materials and current code editions.
C-5 LICENSE
PRACTICE EXAMINATION
,Nevada Concrete Contractor (C-5) — Practice Examination Page 2
SAFETY & OSHA REGULATIONS — Questions 1–35
Q1 What is OSHA's permissible exposure limit (PEL) for respirable crystalline silica in construction?
A) 0.025 mg/m³ as an 8-hr TWA
B) 0.05 mg/m³ as an 8-hr TWA
C) 0.5 mg/m³ as an 8-hr TWA
D) 2 mg/m³ as an 8-hr TWA
Answer: B) 0.05 mg/m³ as an 8-hr TWA
OSHA 29 CFR 1926.1153 sets the PEL at 0.05 mg/m³ as an 8-hour TWA, cutting the previous limit in half to reduce silicosis risk.
Q2 Which hazard is most associated with silica dust generated during concrete grinding?
A) Hearing loss
B) Respiratory disease including silicosis and lung cancer
C) Chemical skin burns
D) Eye strain
Answer: B) Respiratory disease including silicosis and lung cancer
Inhaling fine respirable crystalline silica particles can cause silicosis, a progressive, incurable lung disease, and raises risk of lung
cancer and COPD.
Q3 What is the correct method for lifting heavy concrete forms to prevent back injury?
A) Bend at the waist and pull with the back
B) Twist the torso while lifting
C) Keep the load close to the body and lift with the legs
D) Use only the shoulder muscles
Answer: C) Keep the load close to the body and lift with the legs
Proper lifting requires bending the knees, keeping the load close, and using leg muscles to lift — minimizing spinal stress.
Q4 When must lockout/tagout (LOTO) procedures be implemented on concrete equipment?
A) During routine cleaning only
B) Before starting a new shift
C) When maintenance or repair is being performed
D) Only when OSHA inspectors are present
Answer: C) When maintenance or repair is being performed
OSHA 29 CFR 1910.147 requires LOTO whenever servicing equipment where unexpected energization could injure workers.
Q5 At what minimum height must construction workers be protected by fall protection per OSHA?
A) 4 feet
B) 6 feet
C) 8 feet
D) 10 feet
Answer: B) 6 feet
OSHA 29 CFR 1926.502 requires fall protection at elevations of 6 feet or more above a lower level.
Original practice content for study purposes only. Always consult official NSCB materials and current code editions.
,Nevada Concrete Contractor (C-5) — Practice Examination Page 3
Q6 Wet concrete has an approximate pH of:
A) 6–7
B) 7–8
C) 9–10
D) 12–13
Answer: D) 12–13
Fresh concrete has a pH of 12–13 due to calcium hydroxide produced during cement hydration, causing severe alkali burns with
prolonged skin contact.
Q7 Before any worker enters a permit-required confined space, what must be done first?
A) Get written approval from the project manager
B) Test the atmosphere for oxygen, flammable gas, and toxic vapors
C) Ventilate for a minimum of 60 minutes
D) Notify local fire department
Answer: B) Test the atmosphere for oxygen, flammable gas, and toxic vapors
OSHA 29 CFR 1910.146 requires atmospheric testing before entry — verifying oxygen levels (19.5–23.5%), absence of flammable
gas, and toxic vapors.
Q8 What slope angle is required for Type C soil excavations per OSHA?
A) 90° (vertical)
B) 3/4H:1V
C) 1H:1V
D) 1.5H:1V
Answer: D) 1.5H:1V
OSHA Appendix B to Subpart P classifies Type C soil as requiring a 1.5H:1V (34°) maximum slope to prevent cave-in.
Q9 Spoil piles from an excavation must be placed at least how far from the edge?
A) 1 foot
B) 2 feet
C) 3 feet
D) 5 feet
Answer: B) 2 feet
OSHA 29 CFR 1926.651(j)(2) requires excavated material to be kept a minimum of 2 feet from the edge of any excavation.
Q10 Which PPE is required when using a jackhammer to break concrete?
A) Hard hat only
B) Safety glasses only
C) Hard hat, safety glasses, hearing protection, gloves, and steel-toed boots
D) A respirator only
Answer: C) Hard hat, safety glasses, hearing protection, gloves, and steel-toed boots
Jackhammer operation exposes workers to flying debris, extreme noise (>100 dB), vibration, and foot crush hazards — all listed
PPE is required.
Original practice content for study purposes only. Always consult official NSCB materials and current code editions.
, Nevada Concrete Contractor (C-5) — Practice Examination Page 4
Q11 What is the minimum distance a worker must maintain from an energized overhead power line?
A) 3 feet
B) 5 feet
C) 10 feet
D) 15 feet
Answer: C) 10 feet
OSHA 29 CFR 1926.1408 requires a minimum 10-foot clearance from energized power lines up to 50 kV.
Q12 An SDS for cement must include how many standardized sections per OSHA's Hazard
Communication Standard?
A) 8
B) 12
C) 16
D) 20
Answer: C) 16
OSHA's revised HazCom Standard (29 CFR 1910.1200) requires SDS documents to follow GHS format with exactly 16
standardized sections.
Q13 What type of ladder must extend at least 3 feet above the upper landing surface?
A) Step ladder
B) Extension ladder or job-built ladder
C) Articulating ladder
D) Platform ladder
Answer: B) Extension ladder or job-built ladder
OSHA 29 CFR 1926.1053(b)(1) requires portable ladders to extend at least 3 feet above the upper landing to provide a safe
handhold.
Q14 Hand-arm vibration syndrome (HAVS) from concrete vibrators is a disorder affecting:
A) The cardiovascular system
B) The blood vessels, nerves, and muscles of the hand and arm
C) The respiratory system
D) The auditory system
Answer: B) The blood vessels, nerves, and muscles of the hand and arm
HAVS results from prolonged vibrating tool use, damaging blood vessels and nerves, causing tingling, numbness, and loss of grip
strength.
Q15 Under OSHA's Heat Illness Prevention standard, which is NOT one of the three key prevention
elements?
A) Water
B) Rest
C) Shade
D) Sunscreen
Answer: D) Sunscreen
OSHA's heat illness prevention focuses on three elements: Water, Rest, and Shade. Sunscreen is not part of the official
framework.
Original practice content for study purposes only. Always consult official NSCB materials and current code editions.
