CAA NZ AME Human Factors flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Human Factors

The study of how people interact with their work environment, aimed at reducing error and protecting safety by improving system design, procedures, training, and culture rather than blaming individuals.

Dirty Dozen

Twelve common error precursors: fatigue, complacency, distraction, lack of communication, lack of teamwork, lack of resources, pressure, lack of assertiveness, stress, lack of awareness, norms, and lack of knowledge.

SHEL Model

A human factors framework describing interfaces between Software (procedures, manuals), Hardware (tools, aircraft), Environment (light, noise, temperature), and Liveware (people), where mismatches cause error.

Swiss Cheese Model

Reason's model in which latent conditions and active failures create holes in successive defences; an accident occurs when holes align and the hazard passes through all layers.

Slip

An error in which the intention is correct but the execution is wrong, such as fitting the wrong component or operating the wrong switch, typically due to inattention.

Lapse

A memory-based error in which a planned step is forgotten or omitted, such as missing an item on a checklist, often associated with interruption or fatigue.

Mistake

An error in which the plan itself is wrong; it may be rule-based (misapplying a known rule) or knowledge-based (lacking the knowledge to choose correctly).

Violation

A deliberate deviation from a procedure or rule; it may be routine (accepted practice) or exceptional (situation-driven), and is often linked to impractical procedures or pressure.

Just Culture

A safety culture that consoles honest human error, coaches at-risk behaviour, and sanctions reckless or deliberate violation, encouraging reporting and learning without blame for error.

Situational Awareness

The perception of elements in the environment, comprehension of their meaning, and projection of their future status; loss of situational awareness precedes most errors.

Authority Gradient

The perceived power difference between senior and junior team members; a steep gradient suppresses challenge and increases error, while clear roles with encouraged challenge are safest.

Assertiveness

The ability to state a safety concern clearly and respectfully, ensuring it is heard; it is a key defence against the authority gradient and against unspoken doubts.

Complacency

A state of reduced vigilance following repeated success, where a person assumes a task is safe or correct without deliberate checking; countered by checklists and deliberate verification.

Fatigue

A physiological state of reduced alertness and performance caused by sleep loss, long duty, or circadian disruption; it degrades vigilance, reaction time, and decision quality.

Circadian Rhythm

The body's roughly 24-hour cycle regulating sleep and alertness; low points in the early morning and mid-afternoon increase error risk, especially on night shifts.

Yerkes-Dodson Curve

The inverted-U relationship between arousal and performance: performance improves with arousal to an optimum, then declines; complex tasks have a lower optimum arousal than simple tasks.

Stress

A response to demanding conditions; acute stress narrows attention, while chronic stress impairs memory and judgement, raising error risk and affecting health.

Closed-Loop Communication

A communication protocol in which the sender states a message, the receiver repeats it back, and the sender confirms, catching misheard or misunderstood instructions.

Handover

The transfer of task status between shifts or people, covering open tasks, deferred defects, outstanding inspections, and parts or tools, confirmed by the incoming person.

Task Saturation

A condition in which work demand exceeds a person's capacity, causing narrowing of attention and error; managed by prioritising, delegating, and stopping to reassess.

Vigilance Decrement

The decline in detection performance during a prolonged monitoring task; countered by time-limiting inspections, taking breaks, and rotating staff.

Confirmation Bias

The tendency to seek and interpret evidence that supports an existing belief; countered by actively seeking disconfirming evidence and using independent checks.

Normalisation of Deviance

The gradual acceptance of a deviation from correct practice as normal because it has not yet caused an accident; a key precursor to maintenance error.

Safety Management System

A structured organisational system with four components: safety policy, safety risk management, safety assurance, and safety promotion, used to manage risk proactively.

Risk Assessment

The process of estimating risk as likelihood multiplied by severity, then applying controls in the order eliminate, substitute, engineer, administrate, and use PPE.

MEDA

Maintenance Error Decision Aid: a structured method that identifies an error, its contributing factors at individual, supervisory, and organisational levels, and appropriate corrective actions.

Occurrence Reporting

The formal reporting of errors, near-misses, and incidents through the organisation's system so that causes can be investigated and lessons learned shared.

Fitness to Work

The state of being physically and mentally able to perform a task safely; impaired by illness, fatigue, alcohol, drugs, or stress, and declared rather than hidden.

Independent Inspection

A verification performed by a different person using a different route or method, without prompting the expected answer, to catch slips, lapses, and expectation bias.

Work Card

The authorised document that specifies the task, steps, and sign-offs; it is the authority for the work, and discrepancies must be raised rather than improvised around.

Technical Log

The aircraft record of defects, deferred items, and certifications; entries must be accurate, signed, and traceable to the person and licence.

DECIDE Model

A structured decision-making aid: Define the problem, Establish the facts, Consider options, Identify the best option, Do it, and Evaluate the outcome.