Year 2 Exam Study Guide — master what the exam actually tests, concept by concept.
Mechanical trades involve high pressures, extreme temperatures, rotating machinery, and chemical hazards. The exam tests whether you can identify risks before they become incidents — covering everything from confined space entry to pressure testing safety.
Pneumatic: stored energy dangerous; water testing safer. Safety regulations exist because the consequences of ignoring them are severe — injury, death, or legal liability. Know these requirements the way you know your own name.
Failed refractory: cracks, spalling, brick loss exposing pressure boundary to flame. Safety regulations exist because the consequences of ignoring them are severe — injury, death, or legal liability. Know these requirements the way you know your own name.
Mechanical work is governed by a stack of codes: plumbing codes, gas codes, pressure vessel codes, ASHRAE standards, and provincial regulations. Exam questions test your ability to apply these standards to real scenarios — knowing when a rule applies, what the limit is, and why it exists.
Section I: Steam generating equipment; Section VIII: Unfired pressure vessels. Material selection directly affects performance, code compliance, and longevity. Using the wrong type can fail an inspection or create a hazard down the line.
Corrosion allowance (ca): 1/32" to 1/8" added to minimum thickness; varies by environment. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
UT: sound waves, portable, real-time results, detects planar defects (cracks). On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
PT: dye penetrant soaks into defects, visible under UV; surface/shallow defects. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
Preheat: carbon equivalent (C + Mn/6 + ...) calculated; thicker/higher C = higher preheat. Memorize this formula and practise substituting values — exam questions often give you three variables and ask you to solve for the fourth.
higher C = higher preheat
Hydrostatic: pressurize with water to 1.5 × Pd for 10 min; observe for leaks/bulging. When solving calculation questions, always identify your known variables first, select the correct formula, and double-check your units before calculating.
Scale insulates; even thin scale (1-2mm) reduces efficiency 10-20%. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
Boiler tube thickness: pressure-rated schedule (XS, XXS) or calculated per code. Understanding and applying code requirements correctly ensures your installations pass inspection and meet legal obligations in your jurisdiction.
Mechanical systems live and die by numbers — the wrong pipe size creates pressure loss, the wrong refrigerant charge affects efficiency, the wrong gas orifice is a hazard. These calculations aren't abstract math; they're engineering decisions made in the field every day.
Superheater: adds temperature to saturated steam, increasing heat content and preventing condensation. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
Pipes, valves, fittings, and mechanical components have ratings, classifications, and compatibility requirements. Using the wrong material can fail an inspection, void a warranty, or create a dangerous condition. This section covers proper material selection and equipment knowledge.
Allowable stress: lower of 25% YS or 67% UTS; varies by material and temperature. Material selection directly affects performance, code compliance, and longevity. Using the wrong type can fail an inspection or create a hazard down the line.
Joint efficiency (E): 1.0 (100% RT), 0.85 (spot RT), 0.70 (no exam) per code. Understanding and applying code requirements correctly ensures your installations pass inspection and meet legal obligations in your jurisdiction.
Refractories: high-temp ceramics (firebrick, castable) lining absorbs heat, protects steel. Material selection directly affects performance, code compliance, and longevity. Using the wrong type can fail an inspection or create a hazard down the line.
Expanding (swaging): compresses tube-to-tubesheet junction, improving seal. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
WPS: essential variables (process, base/filler material, diameter, current, voltage, gas, preheat, PWHT). Material selection directly affects performance, code compliance, and longevity. Using the wrong type can fail an inspection or create a hazard down the line.
PWHT: slow heating to ~1100°F, soak, slow cool; relieves residual tensile stress. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
Tube stress: hoop stress (pressure), thermal stress (cycling), axial stress. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
Defects: create stress concentration (fatigue risk), corrosion sites, leak paths. Troubleshooting is a systematic process: identify symptoms, narrow down causes logically, and verify your diagnosis before replacing parts. This logical approach is what examiners want to see.
Water treatment: prevent scale (hardness), corrosion (pH), foaming (alkalinity); periodic blow-down. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
Procedure matters in mechanical work. The order of operations, the proper testing sequence, the way you commission a system — doing it right the first time means no leaks, no callbacks, and no danger. This section covers procedures as they appear on the exam and as they're done on the job.
RT: X-rays/gamma rays show internal density variations; indirect method. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
MT: works on ferrous metals; magnetic field + particles reveal surface and near-surface defects. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
Refractory forms: firebrick (shaped), castable (monolithic), plastic/rammed (installed on-site). Material selection directly affects performance, code compliance, and longevity. Using the wrong type can fail an inspection or create a hazard down the line.
Tube rolling: expands tube radially into tubesheet; mechanical interference prevents leaks. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
PQR: test results (tensile, bend, hardness, chemistry) demonstrating WPS/welder suitability. Material selection directly affects performance, code compliance, and longevity. Using the wrong type can fail an inspection or create a hazard down the line.
ET: electromagnetic induction; detects surface/near-surface defects in metals. On the job, a solid grasp of this concept means faster decisions, fewer errors, and work that passes inspection the first time.
All 26 exam concepts from this guide — test your recall before you sit the exam.