HUMAN FACTORS IN AIRCRAFT MAINTENANCE – The Dirty Dozens and The Safety Nets

COMMON ERRORS IN MAINTENANCE 

Do These Look Familiar?

•      Failure to follow published technical data or local instructions.

•      Using unauthorized procedure or parts not referenced in technical data.

•      Failure to document maintenance properly in maintenance records, work package.

•      Inattention to detail/complacency.

•      Incorrectly installed hardware on an aircraft/engine.

•      Installing the wrong part.

•      Failure to conduct a tool inventory after completion of the task.

•      Personnel not trained or certified to perform the task.

•      Ground support equipment improperly positioned for the task.

WHAT IS DIRTY DOZEN?

•      The “Dirty Dozen” refer to the 12 basic contributing factors that interfere with an individual’s performance during any task.

•      The “Dirty Dozen” are the basic causes of individual performance errors.

•      We need to know and recognize the “Dirty Dozen” in order to achieve effective Risk Management.

•      “Dirty Dozen” is usually the preconditions for unsafe acts.

WHAT IS A SAFETY NET?

A Safety Net is - any regulation, policy, procedure, or practice, that if we have in place may prevent us from becoming a link to an accident.

By establishing personal safety nets, we can break the link that causes the chain of events leading to an accident or error.

DIRTY DOZEN AND RECOMMENDED SAFETY NETS

LACK OF COMMUNICATION

Failure to transmit, receive, or provide enough information to complete a task. Never assume anything. Only 30% of verbal communication is received and understood by either side in a conversation. Others usually remember the first and last part of what you say.

SAFETY NETS

•      For verbal communications -

Always discuss the work to be completed.

Never assume anything – ask questions.

Formulate “mental pictures”.

Repeat what your heard for confirmation.

Obtain feedback.

•      For written communications -

Write to ensure the person reading will understand.

Use simple, clear, concise language.

Have someone else review and critique.

Use proper documentation (logbooks, work cards) to communicate work accomplished.

LACK OF TEAM WORK

Team work is a group of independent individuals working together to achieve a common goal. Lack of team work is failure to work together to complete the common goal.

SAFETY NETS

·         Discuss what has to be done, who will do it, and how it is to be done.

·         Ensure everyone understands the tasks and goals.

·         Have periodic meetings to keep the team together and on the same track.

·         Ensure everyone has the same mental picture of the job.

LACK OF ASSERTIVENESS

Assertiveness is the ability to express yourself, feelings, opinions, beliefs, and needs in a positive and productive manner. Failure to speak up or document concerns about instructions, orders,

or the actions of others.

SAFETY NETS

• For technicians, sign for only work you have completed.
• Refuse to compromise your personal standards.
• Know the procedures.
• Stick to the issue – deal only with facts.
• Provide feedback when a risk or danger is perceived.
• Allow co-workers to give opinions and always accept constructive criticism.

DISTRACTION

A distraction is anything that draws your attention away from performing the task at hand.. Distractions are the #1 cause of forgetting things, including what has or has not been done in a maintenance task.

SAFETY NETS

• Know that a distraction occurred!
• Always complete a task, and if distracted unfasten or     undo the last job.
• Be assertive.  Disregard the phone ring.  Tell the person you are in the middle of a task.
• Always go back at least three steps prior to restarting a task.
• Create a record.  Mark or flag any uncompleted.
• Double-check your work, or have someone else check it for you.
• Always use a checklist.

STRESS

A physical, chemical, or emotional factor that causes physical or mental tension.

SAFETY NETS

• take a short break to get away from the problem.
• exercise.  eat well.  use some humor
• discuss the problem with someone who can help.
• stop – take a few breaths, then look – at the problem rationally, then listen – to what you can control, and finally act – take the task one step at a time

PRESSURE

Pressure can be described as the urgent demands placed upon us that influences our performance. Real or perceived forces demanding high-level job performance.

SAFETY NETS

• know where the pressure is coming from – be sure it is not “self-induced”.
• set realistic goals and expectations with yourself and others.
• do not create a false sense of urgency.
• communicate concerns early.
• ask for help or extra time when required.
• just say “no” when safety is involved.

LACK OF RESOURCES

Not having the right resource, at the right time, nor in the right place, to perform a task properly. Not having enough people, equipment, documentation, time, parts, etc., to complete a task.

SAFETY NETS

• Know where the resources come from.
• Plan ahead – know what parts, materials, manuals will be needed prior to a task.
• Coordinate resources with a business plan.
• Think of the consequences if a resource is not available or is improperly substituted.
• Never replace a part with one that is not compatible for the sake of getting the job done!

LACK OF KNOWLEDGE

Lack of knowledge is having insufficient training or experience to perform a task properly. Shortage of the training, information, and/or ability to successfully perform a task.

SAFETY NETS

• a professional can admit to a lack of knowledge or understanding.  ask questions when in doubt.
• go over procedures before starting a task.
• ensure manuals and procedures are used and up-to-date.
• education and training is continuous.
• only fix parts that you are trained to fix.
• if anything looks different than before, find out why.

LACK OF AWARENESS

Lack of awareness is the failure to recognize the consequences of an action. Failure to recognize a situation, understand what it is, and predict the possible results.

SAFETY NETS

• Ask yourself, the “what if ….?” or “Do I see the complete picture?” question. 
• Ask yourself, “what future problems could arise from my actions?”
• Investigate conflicting information – resolve conflicting facts.
• Check for conflicting repairs or modifications.
• Ask others if they see any problems.

FATIGUE

Fatigue is performance impairment from the loss of sleep and/or our circadian disruption. Physical or mental exhaustion threatening work performance.

SAFETY NETS

• Plan exercise and stretch breaks (reduces stress also).
• Engage in conversation with others.
• Catnaps of short duration (15 minutes).
• Drink plenty of fluids – avoid dehydration.
• Use caffeine strategically to acutely increase alertness
• Rotate different tasks.  Work as a team.  Let others know your condition.
• Plan your work schedule.
• Perform routine tasks  at the beginning of a period.  Forfeit complex tasks if you know you are exhausted.

COMPLACENCY

A state of self-satisfaction accompanied by a loss of awareness to any danger. Overconfidence from repeated experience performing a task.

SAFETY NETS

• Always use a checklist or follow procedures.
• “Today is the day I am going to find a fault.”
• Approach a repetitive task as if it were the first time you are doing it.
• Create challengers for yourself.
• Remember that complacency is an attitude.
• Never sign off on a task that you did not fully check.  Double check your work.

NORMS

A norm is a customary behavior or attitude that develops over time. Expected, yet unwritten, rules of behaviour.

SAFETY NETS

• Refuse to participate in negative norms.  Maintain your integrity.
• Ensure everyone always follow established, written procedures.
• Accentuate positive norms.
• Speak up and refuse to participate in negative norms.
• Periodically review procedures for compliance.
• The easiest way to perform a task may not be the correct way!