ASME B31.3 PROCESS PIPING CODE | REAL EXAM 2026/2027 | EXAM
READY - VERIFIED QUESTIONS AND ANSWERS - COMPREHENSIVE
LATEST VERSION
Q1. What is the full title of ASME B31.3? ANSWER ASME Code for Pressure
Piping, Process Piping.
Q2. What does ASME B31.3 primarily govern? ANSWER The design,
fabrication, assembly, erection, examination, inspection, and testing of process
piping.
Q3. What types of facilities typically use B31.3? ANSWER Petroleum
refineries, chemical plants, pharmaceutical plants, textile plants, paper plants,
semiconductor plants, and cryogenic plants.
Q4. What is the pressure range covered by B31.3? ANSWER All internal
gauge pressures at or above zero, with specific exclusions for very low pressure
systems.
Q5. What systems are EXCLUDED from B31.3 scope per par ANSWER
300.1.3? ANSWER Piping systems designed for internal gauge pressures
below 105 kPa (15 psi) provided the fluid is nonflammable, nontoxic, not
damaging to human tissues, and design temperature is between −29°C (−20°F)
and 186°C (366°F).
Q6. Are fire protection systems covered by B31.3? ANSWER No, fire
protection systems are excluded from B31.3 scope.
Q7. Are building plumbing systems covered by B31.3? ANSWER No, building
plumbing systems are excluded.
Q8. What is the definition of "fluid service" in B31.3? ANSWER A general
term concerning the application of a piping system, considering the
combination of fluid properties, operating conditions, and other factors that
establish the basis for design.
Q9. How many fluid service categories does B31.3 define? ANSWER Four:
Category D, Normal Fluid Service, Category M, and High Pressure Fluid Service.
,Q10. What is Category D Fluid Service? ANSWER A fluid service where: (1)
fluid is nonflammable, nontoxic, and not damaging to human tissues; (2)
design gauge pressure does not exceed 1,035 kPa (150 psi); (3) design
temperature is not greater than 186°C (366°F); and (4) minimum temperature
is not less than −29°C (−20°F).
Q11. What is Category M Fluid Service? ANSWER A fluid service in which the
fluid is so highly toxic that a single exposure to a very small quantity can
produce serious irreversible harm to persons on breathing or bodily contact.
Q12. Can radioactive fluids be classified as Category D? ANSWER No,
radioactive fluids must not be classified as Category D (Appendix Q).
Q13. What is Normal Fluid Service? ANSWER The default fluid service
category that applies when neither Category D, Category M, nor High Pressure
conditions are met.
Q14. What is High Pressure Fluid Service? ANSWER Fluid service for which
the owner specifies the use of Appendix K, typically above Class 2500 ASME
B16.5 rating.
Q15. Who is responsible for assigning the fluid service category? ANSWER
The Design Authority (Owner) must assign a fluid service category to every
piping line on the line list prior to detailed design.
Q16. What is the definition of "designer" in B31.3? ANSWER The person or
organization in responsible charge of the engineering design.
Q17. What is the definition of "fabrication"? ANSWER The preparation of
piping for assembly, including cutting, threading, grooving, forming, bending,
and joining of components into subassemblies.
Q18. What is the definition of "erection"? ANSWER The complete installation
of a piping system in the locations and on the supports designated by the
engineering design.
Q19. What is "cold spring"? ANSWER The intentional deformation of piping
during assembly to produce a desired initial displacement and stress.
Q20. What is the difference between "examination" and "inspection" in
B31.3? ANSWER Examination is performed by the Employer's certified
Examiner (QC function); Inspection is performed by the Owner's Inspector
(verification function).
, Q21. Can the Owner's Inspector function be delegated to the contractor's QC
organization? ANSWER No, the Owner's Inspector function cannot be
delegated to the contractor's quality control organization.
Q22. What are the minimum qualifications for an Owner's Inspector?
ANSWER Per paragraph 340.4(b), the Inspector must have a minimum of 10
years of experience in the design, fabrication, or inspection of industrial
pressure piping, or an engineering degree plus 5 years of experience.
Q23. What units of measurement may be used with B31.3? ANSWER Either
International System (SI/metric) or U.S. Customary units may be used.
Q24. How often are new editions of B31.3 published? ANSWER New editions
are published at intervals of 2 years.
Q25. Is B31.3 retroactive? ANSWER No, this edition of Code Section B31.3 is
not retroactive.
Q26. What happens when no specific edition is specified in a contract?
ANSWER The specific edition is the one issued at least 6 months prior to the
original contract date for the first design activity.
Q27. What is the primary consideration of B31.3? ANSWER Safety is the
primary consideration.
Q28. Does B31.3 serve as a design handbook? ANSWER No, the Code is not a
design handbook and does not serve as a substitute for sound engineering
judgment.
Q29. What is the responsibility of the organization performing calculations?
ANSWER To ensure that a consistent system of units is used.
Q30. What is the role of the Owner per paragraph 300(b)? ANSWER The
Owner holds ultimate compliance responsibility, including designating a
qualified Owner's Inspector.
SECTION 2: DESIGN PRESSURE & TEMPERATURE (Q31–Q60)
Q31. What is "design pressure" per B31.3? ANSWER The most severe
condition of coincident internal or external pressure and temperature
expected during service.
READY - VERIFIED QUESTIONS AND ANSWERS - COMPREHENSIVE
LATEST VERSION
Q1. What is the full title of ASME B31.3? ANSWER ASME Code for Pressure
Piping, Process Piping.
Q2. What does ASME B31.3 primarily govern? ANSWER The design,
fabrication, assembly, erection, examination, inspection, and testing of process
piping.
Q3. What types of facilities typically use B31.3? ANSWER Petroleum
refineries, chemical plants, pharmaceutical plants, textile plants, paper plants,
semiconductor plants, and cryogenic plants.
Q4. What is the pressure range covered by B31.3? ANSWER All internal
gauge pressures at or above zero, with specific exclusions for very low pressure
systems.
Q5. What systems are EXCLUDED from B31.3 scope per par ANSWER
300.1.3? ANSWER Piping systems designed for internal gauge pressures
below 105 kPa (15 psi) provided the fluid is nonflammable, nontoxic, not
damaging to human tissues, and design temperature is between −29°C (−20°F)
and 186°C (366°F).
Q6. Are fire protection systems covered by B31.3? ANSWER No, fire
protection systems are excluded from B31.3 scope.
Q7. Are building plumbing systems covered by B31.3? ANSWER No, building
plumbing systems are excluded.
Q8. What is the definition of "fluid service" in B31.3? ANSWER A general
term concerning the application of a piping system, considering the
combination of fluid properties, operating conditions, and other factors that
establish the basis for design.
Q9. How many fluid service categories does B31.3 define? ANSWER Four:
Category D, Normal Fluid Service, Category M, and High Pressure Fluid Service.
,Q10. What is Category D Fluid Service? ANSWER A fluid service where: (1)
fluid is nonflammable, nontoxic, and not damaging to human tissues; (2)
design gauge pressure does not exceed 1,035 kPa (150 psi); (3) design
temperature is not greater than 186°C (366°F); and (4) minimum temperature
is not less than −29°C (−20°F).
Q11. What is Category M Fluid Service? ANSWER A fluid service in which the
fluid is so highly toxic that a single exposure to a very small quantity can
produce serious irreversible harm to persons on breathing or bodily contact.
Q12. Can radioactive fluids be classified as Category D? ANSWER No,
radioactive fluids must not be classified as Category D (Appendix Q).
Q13. What is Normal Fluid Service? ANSWER The default fluid service
category that applies when neither Category D, Category M, nor High Pressure
conditions are met.
Q14. What is High Pressure Fluid Service? ANSWER Fluid service for which
the owner specifies the use of Appendix K, typically above Class 2500 ASME
B16.5 rating.
Q15. Who is responsible for assigning the fluid service category? ANSWER
The Design Authority (Owner) must assign a fluid service category to every
piping line on the line list prior to detailed design.
Q16. What is the definition of "designer" in B31.3? ANSWER The person or
organization in responsible charge of the engineering design.
Q17. What is the definition of "fabrication"? ANSWER The preparation of
piping for assembly, including cutting, threading, grooving, forming, bending,
and joining of components into subassemblies.
Q18. What is the definition of "erection"? ANSWER The complete installation
of a piping system in the locations and on the supports designated by the
engineering design.
Q19. What is "cold spring"? ANSWER The intentional deformation of piping
during assembly to produce a desired initial displacement and stress.
Q20. What is the difference between "examination" and "inspection" in
B31.3? ANSWER Examination is performed by the Employer's certified
Examiner (QC function); Inspection is performed by the Owner's Inspector
(verification function).
, Q21. Can the Owner's Inspector function be delegated to the contractor's QC
organization? ANSWER No, the Owner's Inspector function cannot be
delegated to the contractor's quality control organization.
Q22. What are the minimum qualifications for an Owner's Inspector?
ANSWER Per paragraph 340.4(b), the Inspector must have a minimum of 10
years of experience in the design, fabrication, or inspection of industrial
pressure piping, or an engineering degree plus 5 years of experience.
Q23. What units of measurement may be used with B31.3? ANSWER Either
International System (SI/metric) or U.S. Customary units may be used.
Q24. How often are new editions of B31.3 published? ANSWER New editions
are published at intervals of 2 years.
Q25. Is B31.3 retroactive? ANSWER No, this edition of Code Section B31.3 is
not retroactive.
Q26. What happens when no specific edition is specified in a contract?
ANSWER The specific edition is the one issued at least 6 months prior to the
original contract date for the first design activity.
Q27. What is the primary consideration of B31.3? ANSWER Safety is the
primary consideration.
Q28. Does B31.3 serve as a design handbook? ANSWER No, the Code is not a
design handbook and does not serve as a substitute for sound engineering
judgment.
Q29. What is the responsibility of the organization performing calculations?
ANSWER To ensure that a consistent system of units is used.
Q30. What is the role of the Owner per paragraph 300(b)? ANSWER The
Owner holds ultimate compliance responsibility, including designating a
qualified Owner's Inspector.
SECTION 2: DESIGN PRESSURE & TEMPERATURE (Q31–Q60)
Q31. What is "design pressure" per B31.3? ANSWER The most severe
condition of coincident internal or external pressure and temperature
expected during service.
