ACI SHOTCRETE NOZZLEMAN CERTIFICATION REAL QUESTIONS +
DETAILED ANSWERS - LATEST VERSION - TOP RATED 2026/2027
1. What is the primary difference between wet-mix and dry-mix shotcrete?
• A) Wet-mix uses more cement
• B) Dry-mix adds water at the nozzle; wet-mix has water added before
pumping
• C) Dry-mix uses larger aggregate
• D) Wet-mix requires more air pressure
ANSWER : B - In dry-mix shotcrete, dry materials are conveyed through the
hose and water is added at the nozzle. In wet-mix, all ingredients including
water are mixed before being pumped through the delivery system
.
2. What is the minimum shooting experience required for full ACI
Shotcrete Nozzleman Certification?
• A) 100 hours
• B) 250 hours
• C) 500 hours total, with 100 hours in the specific process and orientation
• D) 1000 hours
ANSWER : C - Full nozzleman certification requires a minimum of 500 hours
of shooting overall, with at least 100 hours in the specific process (wet or dry)
and orientation (vertical or overhead) being pursued
.
3. What is the Nozzleman-in-Training (NIT) program minimum hour
requirement?
• A) 10 hours
• B) 25 hours
, • C) 50 hours
• D) 100 hours
ANSWER : B - The NIT requires a minimum of only 25 hours of shooting
experience in the process being pursued for certification
.
4. How long is ACI Shotcrete Nozzleman Certification valid?
• A) 2 years
• B) 3 years
• C) 5 years
• D) 10 years
ANSWER : C - The ACI Shotcrete Nozzleman Certification is valid for a
period of 5 years from the date of completion of all certification requirements
.
5. What is the minimum passing grade for the written examination?
• A) 60%
• B) 70%
• C) 75%
• D) 80%
ANSWER : C - The minimum passing grade for the ACI Shotcrete Nozzleman
written examination is 75%
.
6. How many multiple-choice questions are on the written examination?
• A) 40
• B) 50
• C) 60
• D) 80
ANSWER : C - The written exam consists of 60 multiple-choice questions to
be completed in 90 minutes
.
,7. What is the primary purpose of high-velocity material discharge in
shotcrete?
• A) To reduce rebound
• B) To compact the material and drive it around reinforcement
• C) To increase production speed
• D) To reduce water content
ANSWER : B - The high velocity is essential to drive the fresh, wet material
around the reinforcement and into the receiving surface, providing excellent
compaction
.
8. What is the minimum air compressor capacity for wet-mix shotcrete
using a blowpipe?
• A) 100-200 ft³/min
• B) 185-365 ft³/min (5.25-10.5 m³/min)
• C) 400-500 ft³/min
• D) 600-750 ft³/min
ANSWER : B - For wet-mix using a blowpipe, the minimum is 185 to 365
ft³/min (5.25 to 10.5 m³/min)
.
9. What is the minimum air compressor capacity for dry-mix shotcrete?
• A) 185-365 ft³/min
• B) 400-500 ft³/min
• C) 600-750 ft³/min (17-21 m³/min)
• D) 800-1000 ft³/min
ANSWER : C - Dry-mix shotcrete requires 600 to 750 ft³/min (17 to 21
m³/min) due to the need to convey dry materials and add water at the nozzle
.
10. What is the proper nozzle distance from the surface for shotcrete
application?
• A) 6-12 inches (150-300 mm)
, • B) 2-4 feet (0.6-1.2 m)
• C) 5-8 feet (1.5-2.4 m)
• D) 10-15 feet (3-4.5 m)
ANSWER : B - The nozzle with adequate material velocity should be between
2 and 4 feet (0.6 and 1.2 m) from the surface
.
11. What size delivery air hose is required for wet-mix shotcrete nozzles?
• A) 1/4 inch (6.5 mm)
• B) 1/2 inch (13 mm)
• C) 3/4 inch (20 mm)
• D) 1 inch (25 mm)
ANSWER : C - All wet shotcrete nozzles have a minimum of a 3/4 inch (20
mm) air line running into them for maximum material velocity
.
12. What size delivery air hose is required for dry-mix shotcrete nozzles?
• A) 1/4 inch (6.5 mm)
• B) 1/2 inch (13 mm)
• C) 3/4 inch (20 mm)
• D) 2 inch (50 mm)
ANSWER : D - Dry-mix shotcrete requires a 2 inch (50 mm) delivery air hose
.
13. What is "rebound" in shotcrete?
• A) The elastic recovery of shotcrete after placement
• B) Material that bounces off the surface during shooting
• C) The contraction of shotcrete during curing
• D) The expansion of shotcrete during setting
ANSWER : B - Rebound is material (aggregate and cement) that bounces off
the surface during shooting and does not adhere to the substrate
DETAILED ANSWERS - LATEST VERSION - TOP RATED 2026/2027
1. What is the primary difference between wet-mix and dry-mix shotcrete?
• A) Wet-mix uses more cement
• B) Dry-mix adds water at the nozzle; wet-mix has water added before
pumping
• C) Dry-mix uses larger aggregate
• D) Wet-mix requires more air pressure
ANSWER : B - In dry-mix shotcrete, dry materials are conveyed through the
hose and water is added at the nozzle. In wet-mix, all ingredients including
water are mixed before being pumped through the delivery system
.
2. What is the minimum shooting experience required for full ACI
Shotcrete Nozzleman Certification?
• A) 100 hours
• B) 250 hours
• C) 500 hours total, with 100 hours in the specific process and orientation
• D) 1000 hours
ANSWER : C - Full nozzleman certification requires a minimum of 500 hours
of shooting overall, with at least 100 hours in the specific process (wet or dry)
and orientation (vertical or overhead) being pursued
.
3. What is the Nozzleman-in-Training (NIT) program minimum hour
requirement?
• A) 10 hours
• B) 25 hours
, • C) 50 hours
• D) 100 hours
ANSWER : B - The NIT requires a minimum of only 25 hours of shooting
experience in the process being pursued for certification
.
4. How long is ACI Shotcrete Nozzleman Certification valid?
• A) 2 years
• B) 3 years
• C) 5 years
• D) 10 years
ANSWER : C - The ACI Shotcrete Nozzleman Certification is valid for a
period of 5 years from the date of completion of all certification requirements
.
5. What is the minimum passing grade for the written examination?
• A) 60%
• B) 70%
• C) 75%
• D) 80%
ANSWER : C - The minimum passing grade for the ACI Shotcrete Nozzleman
written examination is 75%
.
6. How many multiple-choice questions are on the written examination?
• A) 40
• B) 50
• C) 60
• D) 80
ANSWER : C - The written exam consists of 60 multiple-choice questions to
be completed in 90 minutes
.
,7. What is the primary purpose of high-velocity material discharge in
shotcrete?
• A) To reduce rebound
• B) To compact the material and drive it around reinforcement
• C) To increase production speed
• D) To reduce water content
ANSWER : B - The high velocity is essential to drive the fresh, wet material
around the reinforcement and into the receiving surface, providing excellent
compaction
.
8. What is the minimum air compressor capacity for wet-mix shotcrete
using a blowpipe?
• A) 100-200 ft³/min
• B) 185-365 ft³/min (5.25-10.5 m³/min)
• C) 400-500 ft³/min
• D) 600-750 ft³/min
ANSWER : B - For wet-mix using a blowpipe, the minimum is 185 to 365
ft³/min (5.25 to 10.5 m³/min)
.
9. What is the minimum air compressor capacity for dry-mix shotcrete?
• A) 185-365 ft³/min
• B) 400-500 ft³/min
• C) 600-750 ft³/min (17-21 m³/min)
• D) 800-1000 ft³/min
ANSWER : C - Dry-mix shotcrete requires 600 to 750 ft³/min (17 to 21
m³/min) due to the need to convey dry materials and add water at the nozzle
.
10. What is the proper nozzle distance from the surface for shotcrete
application?
• A) 6-12 inches (150-300 mm)
, • B) 2-4 feet (0.6-1.2 m)
• C) 5-8 feet (1.5-2.4 m)
• D) 10-15 feet (3-4.5 m)
ANSWER : B - The nozzle with adequate material velocity should be between
2 and 4 feet (0.6 and 1.2 m) from the surface
.
11. What size delivery air hose is required for wet-mix shotcrete nozzles?
• A) 1/4 inch (6.5 mm)
• B) 1/2 inch (13 mm)
• C) 3/4 inch (20 mm)
• D) 1 inch (25 mm)
ANSWER : C - All wet shotcrete nozzles have a minimum of a 3/4 inch (20
mm) air line running into them for maximum material velocity
.
12. What size delivery air hose is required for dry-mix shotcrete nozzles?
• A) 1/4 inch (6.5 mm)
• B) 1/2 inch (13 mm)
• C) 3/4 inch (20 mm)
• D) 2 inch (50 mm)
ANSWER : D - Dry-mix shotcrete requires a 2 inch (50 mm) delivery air hose
.
13. What is "rebound" in shotcrete?
• A) The elastic recovery of shotcrete after placement
• B) Material that bounces off the surface during shooting
• C) The contraction of shotcrete during curing
• D) The expansion of shotcrete during setting
ANSWER : B - Rebound is material (aggregate and cement) that bounces off
the surface during shooting and does not adhere to the substrate
