Expanded Level 2 authority and responsibilities, AWS D1.1 visual acceptance criteria, ASME Section V and VIII requirements, code application to specific findings, and comparison of static vs. dynamic loading acceptance limits.
Level 2 Authority and Code Application
The Expanded Role of VT Level 2
VT Level 2 represents a significant expansion of authority and responsibility compared to Level 1. The Level 2 is the principal decision-maker for inspection operations and the technical authority responsible for the quality and accuracy of examination results.
Level 2 Authority Under SNT-TC-1A
Level 2 CAN:
- Set up and verify the performance of test systems and equipment
- Conduct tests using established procedures
- Interpret and evaluate results per applicable codes and standards
- Make formal accept/reject decisions
- Prepare technical reports documenting examination findings and dispositions
- Organize, direct, and instruct Level 1 personnel
- Prepare written inspection procedures (subject to Level 3 approval)
Level 2 CANNOT (without specific authorization):
- Approve the employer's Written Practice (requires Level 3)
- Certify personnel at Level 2 or Level 3 (requires Level 3)
- Develop fundamentally new examination techniques without procedure qualification
The Critical Difference: Interpretation vs. Identification
Level 1 identifies what they see. Level 2 interprets what it means.
A Level 1 sees 'a linear indication, 3/4 inch long, at the weld toe.' A Level 2 evaluates whether this is a crack (rejectable under all codes) or a tight surface irregularity from grinding (possibly non-relevant), applies the acceptance criterion, and issues a formal accept or reject decision with documented technical justification.
Code Hierarchy
Applying acceptance criteria requires understanding the hierarchy of governing documents:
1. Law/Regulation: Federal and state regulations (OSHA, NRC, DOT) supersede all
2. Code of Record: The construction code (ASME Section VIII, AWS D1.1, B31.3) defines minimum requirements
3. Project Specification: May be more restrictive than the code — always apply the more stringent requirement
4. Drawing/Engineering Document: Specific weld size, location, and quality requirements
5. WPS/Inspection Procedure: How the work is to be performed
When a drawing specification is more stringent than the code, apply the drawing specification. When a code is more stringent than the drawing, apply the code. Always apply the most restrictive requirement.
Key VT Level 2 Code Authorities
SNT-TC-1A 2020, Section 6.3 — Level II Requirements:
- Training: Minimum 24 classroom hours for VT Level 2
- Experience: Minimum 6 months combined Level 1 + Level 2 VT work experience
- Examination: General and specific written exams; practical examination
- Authority: 'The Level II shall be capable of evaluating test results with respect to applicable codes, standards, and specifications'
AWS D1.1:2020 Section 6.1.3 — Inspector Duties:
The inspector (functioning at Level 2) 'shall have authority to reject work that does not conform to this code. Controversies, when not resolved, shall be resolved by the engineer.' This establishes the Level 2's direct authority to reject nonconforming welds.
ASME Section V, Article 9:
Distinguishes between the 'examiner' (the person performing the examination — often Level 1) and the 'reviewer' (the person evaluating and accepting results — Level 2 or above). The reviewer's evaluation and signature constitute the formal accept decision.
ASME Section VIII, UW-35:
Defines weld surface condition requirements including maximum undercut, overlap, and reinforcement limits for pressure vessel welds — the specific criteria applied by the Level 2 when evaluating ASME vessel welds.
Making the Level 1 → Level 2 Mental Transition
The hardest part of moving to Level 2 is not learning new code criteria — it is accepting responsibility for making and defending your own evaluation decisions.
Own your accept decisions as much as your reject decisions. Many new Level 2 inspectors are vigilant about documenting why they rejected something, but casual about accepting welds. Every acceptance is also a technical decision — document the basis for significant accepts too, particularly for indications that are close to limits.
Know when to escalate to a Level 3. Level 2 does not mean you know everything. When you encounter a finding that is outside your code knowledge, involves an unusual material or process, or raises a safety concern you cannot fully assess, escalate to the Level 3. This is professionalism, not weakness.
Production pressure is real — your authority is also real. You will face situations where rejecting a weld disrupts production schedules and creates significant cost pressure. SNT-TC-1A and AWS D1.1 explicitly give you the authority to reject nonconforming work. Use it. The integrity of the structure depends on it.
Document your evaluation reasoning for borderline cases. For indications near the acceptance limit, note in your report that the measurement was X, the limit is Y, the finding is accept (or reject), and any relevant observations. This protects you if the decision is later questioned.
Applying AWS D1.1 and ASME Visual Acceptance Criteria
Visual Acceptance Criteria: From Code to Field Decision
AWS D1.1 Table 6.1 — Visual Inspection Criteria Summary
AWS D1.1 provides the most widely used visual acceptance criteria for structural steel welding. Understanding this table is essential for any Level 2 working on structural fabrication:
Rejectable Conditions (Zero Tolerance):
- Cracks: Any crack, any size, any location — automatically rejectable
- Incomplete fusion: Any visible incomplete fusion at the weld face or toes
- Overlap: Any weld metal flowing over base metal without fusion
- Arc strikes: On primary members (varies by engineer's discretion for minor cases)
Dimensional Limits:
| Condition | Statically Loaded | Dynamically Loaded |
|---|---|---|
| Undercut (parallel to stress) | Max 1/32 inch | Max 1/32 inch |
| Undercut (transverse to stress) | Max 1/16 inch | Max 1/32 inch |
| Reinforcement (t ≤ 1") | Max 1/8 inch | Max 1/8 inch |
| Reinforcement (t > 1") | Max 3/16 inch | Max 3/16 inch |
| Undersized fillet weld | Not more than 1/16" under specified size for max 10% of weld length | Not permitted |
Porosity Limits (AWS D1.1 Statically Loaded):
- Individual pore: Maximum diameter = 3/8 t or 3/8 inch (smaller governs)
- Per 1 inch of weld: Maximum aggregate area = 3/8 inch
- Per 12 inches of weld: Maximum aggregate area = 3/4 inch
ASME Section VIII UW-35 Criteria Summary
ASME pressure vessel welds must meet:
- Undercut: Maximum 1/32 inch for most applications
- Reinforcement: Per UW-35 table based on plate thickness
- Weld face: Free from cracks, incomplete fusion, and porosity (limits per application)
- Alignment (joint offset): Per UW-33 (max 1/4 t, not to exceed 1/8 inch for most applications)
Applying Criteria — Step by Step
1. Identify the governing code (AWS D1.1? ASME VIII? B31.3?)
2. Identify the structural category (static vs. dynamic loading in AWS; Normal vs. High-Purity in B31.3)
3. Identify the discontinuity type — different criteria apply to different discontinuity types
4. Measure precisely — use calibrated gauges; do not estimate
5. Compare to the specific limit for that discontinuity type in that structural category
6. Document the comparison — acceptance or rejection with specific measurements cited
Acceptance Criteria Reference Matrix for Level 2
AWS D1.1:2020, Table 6.1:
Complete visual inspection acceptance criteria for all conditions in statically and dynamically loaded structural connections. This table must be memorized and instantly accessible during field evaluations.
ASME Section VIII, Division 1, UW-35:
Weld surface requirements for pressure vessels. Undercut maximum: 1/32 inch for Code welds. Reinforcement limits: tabulated by base metal thickness from 0 to over 2 inches.
ASME B31.3, Table 341.3.2:
Visual examination acceptance criteria for process piping. Different criteria apply to: Normal Fluid Service, Category D, High Pressure, and High Purity service.
AWS D1.5 Bridge Welding Code:
More restrictive than D1.1 for dynamically loaded bridge members. Undercut limits, porosity limits, and weld profile requirements are more stringent than D1.1. Level 2 inspectors on bridge fabrication projects must be familiar with D1.5 specifically.
API 1104 (Pipeline Welding):
Governing code for oil and gas pipeline girth welds. Visual acceptance criteria in Section 9 — fundamentally different from D1.1 and ASME criteria; specifically addresses longitudinal and transverse weld quality requirements for pressurized pipeline service.
Reading Table 6.1 Under Field Conditions
AWS D1.1 Table 6.1 is a reference table — not a summary. Field application requires careful attention:
'Static' vs. 'Dynamic' loading is an engineering determination. You do not always know from visual inspection whether a connection is statically or dynamically loaded. Ask for the design documentation. If you cannot determine it, apply the more restrictive (dynamic) criteria.
Porosity evaluation requires counting AND measuring. AWS D1.1 porosity criteria require you to: (1) measure individual pore size, (2) count pores in each 1-inch weld length, (3) sum their diameters in any 1-inch length, and (4) sum their diameters in any 12-inch length. This takes time but is not optional.
Undercut depth measurement is critical. The most common error in undercut evaluation is estimating depth visually. Always use a calibrated depth gauge (bridge cam, taper gauge) to measure actual depth. Visual estimates are almost always different from actual measurements.
Document the measurement, not just the conclusion. Your report should state: 'Undercut measured at 0.028 inch maximum depth, 1.5 inches long. Limit per AWS D1.1 Table 6.1 for static structure, transverse to stress direction: 1/16 inch (0.063 inch). Finding: ACCEPTABLE.' This level of documentation is necessary for an auditable record.