Technical Trade SchoolBAS-100 foundation-series
BAS-108
Ten concept and evidence figures

BAS-108 Visual Aid Library

Figure-use rule

Each figure is an orientation and reasoning aid, not a project drawing. Learners must pair it with the current sequence, point list, wiring/piping documents, manufacturer instructions, and as-found evidence.

Figure 1 — Electrical hazard model and why control voltage is not zero risk critical

Normal-rule anchor

Low-voltage control work may be adjacent to higher energy and can still create shock, fire, equipment, and unexpected-start hazards.

Case overlay

A 24 Vac BAS panel shares an enclosure and control transformer with 480 V motor circuits.

Calculation/evidence callout: Use supplied risk data to compare exposure/consequence, inventory energy sources, and calculate hazard-control coverage without deriving field boundaries.

Figure 2 — Qualified, unqualified, competent and authorized roles critical

Normal-rule anchor

Course completion, job title, tenure, or confidence does not make a person qualified for every electrical task.

Case overlay

A BAS technician trained on 24 Vac controls is asked to open a 480 V VFD cabinet to check terminals.

Calculation/evidence callout: Calculate task-role coverage and critical gaps; no average score overrides a missing required qualification.

Figure 3 — Establishing an electrically safe work condition conceptually critical

Normal-rule anchor

Off, stopped, open command, zero display, and disconnect handle position are not substitutes for the employer process and qualified verification.

Case overlay

A fan is stopped from BAS and the disconnect handle is off, but a control transformer has a separate source.

Calculation/evidence callout: Reconcile identified/isolated/locked/verified energy-source counts and calculate critical sequence coverage.

Figure 4 — Hazardous-energy control and LOTO responsibilities critical

Normal-rule anchor

A BAS command or software disable is a control function, not an energy-isolating device unless the employer procedure specifically establishes an approved method.

Case overlay

An AHU has electrical, pneumatic, gravity, spring, pressure, and thermal energy during actuator replacement.

Calculation/evidence callout: Count/reconcile sources, isolation devices, authorized workers, lock records, shift transfer, and release checks.

Figure 5 — One-lines, labels, equipment condition and task planning critical

Normal-rule anchor

A label informs the qualified risk assessment but is not permission, a complete procedure, or proof that equipment identity/condition is current.

Case overlay

The panel label and one-line disagree on source and the equipment door is damaged.

Calculation/evidence callout: Reconcile identity/source/label dates and calculate document/condition coverage; refer boundary/PPE values to qualified program decisions.

Figure 6 — Shock and arc-flash risk assessment awareness critical

Normal-rule anchor

Learners do not calculate or establish field boundaries or incident energy from generic course examples; current study, labels, program, and qualified assessment govern.

Case overlay

A technician proposes opening energized equipment for convenience because shutting down affects occupants.

Calculation/evidence callout: Apply only supplied boundaries/risk matrix, calculate exposure duration and control coverage, and identify unacceptable missing inputs.

Figure 7 — Meters, test instruments, categories and test-before-touch boundaries critical

Normal-rule anchor

A meter and PPE are parts of a qualified procedure; ownership and correct dial position do not control electrical risk.

Case overlay

A technician attempts resistance measurement on a circuit that has not been verified de-energized.

Calculation/evidence callout: Predict expected readings, inspect rating/method coverage, and calculate uncertainty/tolerance only from supplied safe data.

Figure 8 — PPE, tools, barriers and emergency preparedness awareness critical

Normal-rule anchor

PPE does not make unjustified energized work acceptable and must be selected, maintained, and used under the employer program.

Case overlay

An expired glove test date and damaged face shield are found just before work.

Calculation/evidence callout: Calculate inspection/date coverage and critical readiness; all required items must pass before authorized work.

Figure 9 — BAS-specific electrical interfaces and remote-operation hazards critical

Normal-rule anchor

A software stop, disabled schedule, or network disconnect is not energy isolation; remote access must be coordinated with physical work and LOTO.

Case overlay

A remote learner commands a fan while an OJL technician is inspecting the belt and starter.

Calculation/evidence callout: Calculate command/proof timing, session/access coverage, workers/assets accounted for, and temporary-state/restoration closure.

Figure 10 — Abnormal events, shock response, near misses and incident records; Release from LOTO, restoration, handoff and safety defense critical

Normal-rule anchor

After an electrical event, protect people, call the correct response, and preserve evidence; reset/reenergization requires authorized investigation and acceptance. Restoration is a controlled hazardous phase; removing the last lock is not the end of the job.

Case overlay

A breaker trips with flash/sound while a worker reports tingling and no visible injury. Changed case: After maintenance, a BAS override, local HOA switch, open panel cover, and absent worker remain unresolved.

Calculation/evidence callout: Calculate response/report timeline from supplied program criteria, account for people/equipment, and score factual evidence/control follow-up. Reconcile all restoration inventories, calculate completion/critical holds, and compare expected/actual startup without authorizing field action.