10.1 Part A (Fundamentals) Exam Strategies

Part A Format and Time Budget

Part A (Fundamentals) is the closed-book pillar of the CWI exam, built to the AWS B5.1 standard for inspector qualification. You answer 150 scored questions plus 15 unscored pretest questions (165 total) in a 2-hour window — roughly 48 seconds per question. No code book, no notes, no reference screens: every answer comes from memory. The passing score is 72%, so you need 108 of 150 correct and may miss 42 and still pass.

Pacing rule: on the first pass, never burn more than 60 seconds on one item — flag it and move on. Recall is fastest when fresh, so harvest the easy points first, then spend the recovered minutes on flagged items. Leave 5–8 minutes to confirm no question is left blank; there is no wrong-answer penalty, so guess every remaining item.

Where to Spend Closed-Book Study

Part A draws from welding processes, NDE, safety, quality assurance, inspector duties, discontinuities, weld symbols, joint design, mechanical properties, and on-the-job math. The highest-yield closed-book targets are the ones that hinge on exact wording or a memorized number:

High-Yield Integrated Review — Processes and Discontinuities

Use these compact tables as a last-pass cram. First, the five major arc processes — the single most-tested cluster:

Next, the discontinuity-to-cause map — the exam loves "what caused this?" items:

Trap: A crack is rejectable regardless of size or location under D1.1; overlap, IF, and ICP are linear discontinuities that usually fail too. Porosity and slag are rounded/volumetric and judged against size limits.

High-Yield Review — NDE, Symbols, and Formulas

NDE surface vs volumetric is a guaranteed cluster. Memorize what each method finds:

Memory hook: PT/MT = surface; RT/UT = subsurface; RT favors volumetric, UT favors planar.

Weld symbol sides (arrow vs other):

The two formulas you must reproduce cold:

• Heat input: HI (kJ/in) = (Volts × Amps × 60) ÷ (Travel speed in/min × 1000). Example: 24 V × 180 A × 60 ÷ (8 × 1000) = 32.4 kJ/in.
• Carbon equivalent (IIW): CE = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15. Higher CE → greater hardenability → more martensite risk → more preheat to avoid hydrogen-induced cracking (HIC). HIC needs all three: susceptible (martensitic) microstructure, diffusible hydrogen, and tensile stress — remove any one to prevent it.

D1.1 acceptance values to remember: cracks prohibited; undercut depth limit generally 1/16 in (1.6 mm) with tighter limits on cyclically loaded members; fillet weld profiles must avoid excessive convexity/concavity; craters must be filled to full cross-section.

Part A Readiness Checklist (Last Cram Pass)

• Recite each of the five processes' power source, polarity, shielding, and position limits without notes
• Map every common discontinuity to its cause and the NDE method that finds it
• State which NDE methods are surface-only and which find subsurface/volumetric flaws
• Place a weld symbol on the correct side from memory (below = arrow side)
• Write and solve heat input and carbon equivalent from a blank page
• List the three HIC conditions and one way to break each
• Confirm pace: stop at 60 s/question, flag, return, guess every blank at the end

Trap-avoidance: read all four options; distrust always/never/only; watch unit swaps (ksi vs psi, °F vs °C, in vs mm); and know old-vs-new term pairs — DCEP = DCRP, DCEN = DCSP.