What certifications should you require when hiring pipefitters?
ASME B31.3 Process Piping is the baseline standard for most industrial process piping work — refineries, chemical plants, pharmaceutical facilities. ASME B31.1 governs power piping (boiler and steam systems). Requiring the wrong code, or failing to specify code entirely, is a common procurement error that leads to mismatched placements and rework risk on live systems.
Matching the correct certification to the scope of work requires understanding what each code covers:
- ASME B31.3 Process Piping: Chemical plant, refinery, and pharmaceutical process piping. The most common requirement for industrial facility maintenance and turnaround work.
- ASME B31.1 Power Piping: Boiler and steam system piping. Power generation facilities and industrial boiler systems.
- NCCER Pipefitter Level 4: The standard journeyman-level industrial pipefitter credential. Appropriate for general plant work that does not require specific code qualifications.
- UA Journeyman: Union plumber/pipefitter credential. Required for dispatch through UA locals in union markets.
How do you evaluate a staffing agency's pipefitter screening process?
The quality of a pipefitter placement depends on the staffing agency's screening process — because certification verification is complex and shortcuts are easy to take. Before using an agency for pipefitter placements, ask specifically:
- How do you verify ASME qualification records? (Correct answer: WPS and PQR documentation maintained on file; employer-based qualifications require verification with the qualifying employer)
- What trades-specific questions do you ask beyond the certification card? (Look for questions about pipe support, hydrostatic testing, fit-up tolerances, and LOTO experience)
- Have your pipefitters worked on hot work permits in classified environments? (Critical for refinery and chemical plant placements)
- What is your replacement guarantee if a pipefitter fails a facility qualification test?
What should a qualified pipefitter know beyond the certification?
Certification documents procedure qualification. Operational competence includes knowledge that distinguishes experienced field pipefitters from those who passed a test but have limited real-world experience: pipe support and hanger types and spacing; hydrostatic test procedures and required documentation; bolt torquing sequences for flanged joints; spring hanger adjustment for thermal expansion; and the difference between Class 150, 300, and 600 flange ratings.
When interviewing pipefitters — or evaluating whether a staffing agency screens for these skills — these operational knowledge areas are the best differentiators of genuine experience. For salary benchmarks to build competitive offers, see the pipefitter salary guide. For shutdown-specific screening requirements, see the shutdown staffing checklist.
Common pipefitter hiring mistakes and how to avoid them
| Mistake | Consequence | How to Avoid |
|---|---|---|
| Requiring wrong code for the application | Mismatched candidates; rework risk | Specify code, material, and pressure rating in the requisition |
| Not verifying continuity of qualification | Expired certification; safety exposure | Confirm pipefitter has not had a break in process use exceeding 6 months |
| No facility qualification test | Discovering deficiencies after work begins | Require a short fitment test before production work begins |
| Not requiring proof of insurance from agency | Workers' comp liability exposure | Always require a COI naming your facility before any work starts |
| Accepting verbal shutdown experience claims | Placing an under-skilled worker on critical systems | Ask for specific site names, dates, and reference contacts from previous shutdowns |