IADC Level 3 Well Control Operations Exam
Questions and Answers with Rationales| Latest Update
covers core Level 3 (Supervisor) well control topics: pressure fundamentals, kick
detection, shut-in procedures, kill methods (Driller’s, Wait and Weight, Volumetric,
Bullheading), kill sheet calculations, MAASP and kick tolerance, BOP and choke manifold
equipment, accumulator systems, stripping/snubbing, gas migration, special well control
problems, and testing/documentation.
,1. Primary well control is maintained by:
A) The BOP stack
B) The hydrostatic pressure of the drilling fluid column
C) The choke manifold
D) The kelly cock
Answer: B
Rationale: Primary control relies on the hydrostatic pressure of the fluid column
exceeding formation pressure. Secondary well control (BOP, choke) is only engaged
once primary control is lost.
2. A kick is best defined as:
A) Loss of returns to the formation
B) An unscheduled entry of formation fluids into the wellbore
C) A sudden increase in mud weight
D) Excessive torque on the drill string
Answer: B
Rationale: A kick occurs when formation fluid enters the wellbore because formation
pressure exceeds the hydrostatic pressure of the mud column.
3. Which of the following is one of the two most reliable indicators of a kick while
drilling?
A) Increase in pit volume
B) Change in pump pressure alone
C) A drilling break
D) Gas at surface
Answer: A
Rationale: An increase in active pit volume (pit gain) directly indicates fluid entering
the wellbore and, along with flow rate increase, is one of the most reliable primary
kick indicators.
,4. Causes of a kick include all of the following EXCEPT:
A) Insufficient mud weight
B) Swabbing while tripping
C) Lost circulation (reducing hydrostatic head)
D) Increasing mud weight above formation pressure
Answer: D
Rationale: Raising mud weight above formation pressure increases the safety margin
and helps prevent a kick rather than cause one.
5. Swabbing is most likely to occur when:
A) Running in hole too fast
B) Pulling out of hole too fast, especially with a balled-up BHA
C) Circulating bottoms up
D) Increasing pump rate
Answer: B
Rationale: Rapid upward pipe movement, particularly with a bit or BHA that acts like
a piston, reduces bottomhole pressure and can swab formation fluid into the well.
6. Surge pressure while running pipe into the hole can most directly lead to:
A) A kick
B) Lost circulation or formation fracture
C) Stuck pipe only
D) Gas migration
Answer: B
Rationale: Running pipe too fast increases annular pressure (surge), which can
exceed the formation fracture gradient and induce losses.
, 7. The purpose of a trip tank is to:
A) Store excess mud for mixing
B) Accurately monitor hole fill or displacement volume while tripping
C) Mix chemicals into the mud
D) Measure the gas content of returns
Answer: B
Rationale: A trip tank provides an accurate, continuously monitored small-volume
system to confirm the hole is taking or giving back the correct calculated volume
during trips.
8. Which shut-in method closes the BOP element first and then opens the choke line
valve?
A) Hard shut-in
B) Soft shut-in
C) Volumetric method
D) Bullheading
Answer: A
Rationale: In a hard shut-in, the preventer is closed immediately with the choke line
valve already shut, stopping flow as fast as possible.
9. The soft shut-in procedure is preferred by some operators because it:
A) Is always faster than a hard shut-in
B) Reduces water-hammer/shock pressure by opening the choke line valve before
closing the BOP
C) Requires no choke manifold
D) Eliminates the need for an annular preventer
Answer: B
Rationale: Opening the choke line valve first allows flow to be diverted through the
manifold as the preventer closes, reducing the pressure surge compared to closing
everything simultaneously.
Questions and Answers with Rationales| Latest Update
covers core Level 3 (Supervisor) well control topics: pressure fundamentals, kick
detection, shut-in procedures, kill methods (Driller’s, Wait and Weight, Volumetric,
Bullheading), kill sheet calculations, MAASP and kick tolerance, BOP and choke manifold
equipment, accumulator systems, stripping/snubbing, gas migration, special well control
problems, and testing/documentation.
,1. Primary well control is maintained by:
A) The BOP stack
B) The hydrostatic pressure of the drilling fluid column
C) The choke manifold
D) The kelly cock
Answer: B
Rationale: Primary control relies on the hydrostatic pressure of the fluid column
exceeding formation pressure. Secondary well control (BOP, choke) is only engaged
once primary control is lost.
2. A kick is best defined as:
A) Loss of returns to the formation
B) An unscheduled entry of formation fluids into the wellbore
C) A sudden increase in mud weight
D) Excessive torque on the drill string
Answer: B
Rationale: A kick occurs when formation fluid enters the wellbore because formation
pressure exceeds the hydrostatic pressure of the mud column.
3. Which of the following is one of the two most reliable indicators of a kick while
drilling?
A) Increase in pit volume
B) Change in pump pressure alone
C) A drilling break
D) Gas at surface
Answer: A
Rationale: An increase in active pit volume (pit gain) directly indicates fluid entering
the wellbore and, along with flow rate increase, is one of the most reliable primary
kick indicators.
,4. Causes of a kick include all of the following EXCEPT:
A) Insufficient mud weight
B) Swabbing while tripping
C) Lost circulation (reducing hydrostatic head)
D) Increasing mud weight above formation pressure
Answer: D
Rationale: Raising mud weight above formation pressure increases the safety margin
and helps prevent a kick rather than cause one.
5. Swabbing is most likely to occur when:
A) Running in hole too fast
B) Pulling out of hole too fast, especially with a balled-up BHA
C) Circulating bottoms up
D) Increasing pump rate
Answer: B
Rationale: Rapid upward pipe movement, particularly with a bit or BHA that acts like
a piston, reduces bottomhole pressure and can swab formation fluid into the well.
6. Surge pressure while running pipe into the hole can most directly lead to:
A) A kick
B) Lost circulation or formation fracture
C) Stuck pipe only
D) Gas migration
Answer: B
Rationale: Running pipe too fast increases annular pressure (surge), which can
exceed the formation fracture gradient and induce losses.
, 7. The purpose of a trip tank is to:
A) Store excess mud for mixing
B) Accurately monitor hole fill or displacement volume while tripping
C) Mix chemicals into the mud
D) Measure the gas content of returns
Answer: B
Rationale: A trip tank provides an accurate, continuously monitored small-volume
system to confirm the hole is taking or giving back the correct calculated volume
during trips.
8. Which shut-in method closes the BOP element first and then opens the choke line
valve?
A) Hard shut-in
B) Soft shut-in
C) Volumetric method
D) Bullheading
Answer: A
Rationale: In a hard shut-in, the preventer is closed immediately with the choke line
valve already shut, stopping flow as fast as possible.
9. The soft shut-in procedure is preferred by some operators because it:
A) Is always faster than a hard shut-in
B) Reduces water-hammer/shock pressure by opening the choke line valve before
closing the BOP
C) Requires no choke manifold
D) Eliminates the need for an annular preventer
Answer: B
Rationale: Opening the choke line valve first allows flow to be diverted through the
manifold as the preventer closes, reducing the pressure surge compared to closing
everything simultaneously.
