MSHA Respirable Crystalline Silica Compliance
Training Certification Practice Exam Questions
And Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. What is respirable crystalline silica (RCS)?
A. A type of coal dust
B. Tiny particles of crystalline silica small enough to enter the
lungs
C. Water vapor in mines
D. Organic soil dust
RCS refers to crystalline silica particles that are small enough to
penetrate deep into the lungs, potentially causing silicosis and
other respiratory diseases.
2. Which occupational disease is most commonly associated with
RCS exposure?
A. Pneumonia
B. Asthma
C. Silicosis
D. Bronchitis
Silicosis is a progressive lung disease caused by inhaling respirable
crystalline silica over time.
3. What size of silica particles is considered respirable?
A. Larger than 10 microns
B. 10 microns or smaller
C. 50–100 microns
, D. Any visible dust
Particles smaller than 10 microns can reach the alveoli, where gas
exchange occurs, making them respirable.
4. Which mining activity produces the highest levels of RCS?
A. Operating ventilation fans
B. Drilling and cutting of rock containing quartz
C. Inspecting equipment
D. Administrative tasks in the office
Drilling, cutting, and crushing quartz-containing rock releases fine
dust particles that are respirable.
5. Which federal agency regulates occupational silica exposure in the
U.S.?
A. EPA
B. FDA
C. OSHA
D. CDC
OSHA sets permissible exposure limits (PELs) for respirable
crystalline silica in workplaces, including mines.
6. What is the current OSHA PEL for RCS in general industry?
A. 0.05 mg/m³
B. 0.05 mg/m³ as an 8-hour TWA
C. 0.25 mg/m³
D. 1 mg/m³
The PEL is 0.05 milligrams per cubic meter of air averaged over an
8-hour shift.
7. What does TWA stand for?
A. Total Work Area
, B. Time-Weighted Average
C. Time-Weighted Average
D. Threshold Work Alert
TWA represents the average airborne concentration over an 8-
hour work shift.
8. Which engineering control is most effective at reducing RCS
exposure?
A. Respirators
B. Water sprays and ventilation systems
C. Wearing gloves
D. Safety glasses
Engineering controls like water sprays and local exhaust
ventilation reduce dust at the source.
9. When are respirators required for silica exposure?
A. Only during inspections
B. Only in summer
C. When engineering controls cannot reduce exposure below the
PEL
D. Always, regardless of exposure
Respirators are a secondary control used only when other
measures are insufficient.
10. What type of respirator is approved for RCS protection?
A. Cloth mask
B. Surgical mask
C. N95 or higher particulate respirator
D. Gas mask
Training Certification Practice Exam Questions
And Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. What is respirable crystalline silica (RCS)?
A. A type of coal dust
B. Tiny particles of crystalline silica small enough to enter the
lungs
C. Water vapor in mines
D. Organic soil dust
RCS refers to crystalline silica particles that are small enough to
penetrate deep into the lungs, potentially causing silicosis and
other respiratory diseases.
2. Which occupational disease is most commonly associated with
RCS exposure?
A. Pneumonia
B. Asthma
C. Silicosis
D. Bronchitis
Silicosis is a progressive lung disease caused by inhaling respirable
crystalline silica over time.
3. What size of silica particles is considered respirable?
A. Larger than 10 microns
B. 10 microns or smaller
C. 50–100 microns
, D. Any visible dust
Particles smaller than 10 microns can reach the alveoli, where gas
exchange occurs, making them respirable.
4. Which mining activity produces the highest levels of RCS?
A. Operating ventilation fans
B. Drilling and cutting of rock containing quartz
C. Inspecting equipment
D. Administrative tasks in the office
Drilling, cutting, and crushing quartz-containing rock releases fine
dust particles that are respirable.
5. Which federal agency regulates occupational silica exposure in the
U.S.?
A. EPA
B. FDA
C. OSHA
D. CDC
OSHA sets permissible exposure limits (PELs) for respirable
crystalline silica in workplaces, including mines.
6. What is the current OSHA PEL for RCS in general industry?
A. 0.05 mg/m³
B. 0.05 mg/m³ as an 8-hour TWA
C. 0.25 mg/m³
D. 1 mg/m³
The PEL is 0.05 milligrams per cubic meter of air averaged over an
8-hour shift.
7. What does TWA stand for?
A. Total Work Area
, B. Time-Weighted Average
C. Time-Weighted Average
D. Threshold Work Alert
TWA represents the average airborne concentration over an 8-
hour work shift.
8. Which engineering control is most effective at reducing RCS
exposure?
A. Respirators
B. Water sprays and ventilation systems
C. Wearing gloves
D. Safety glasses
Engineering controls like water sprays and local exhaust
ventilation reduce dust at the source.
9. When are respirators required for silica exposure?
A. Only during inspections
B. Only in summer
C. When engineering controls cannot reduce exposure below the
PEL
D. Always, regardless of exposure
Respirators are a secondary control used only when other
measures are insufficient.
10. What type of respirator is approved for RCS protection?
A. Cloth mask
B. Surgical mask
C. N95 or higher particulate respirator
D. Gas mask
