MEA154: Apply Work Health and Safety Practices in Aviation Maintenance Note

Jet-Engine Blast and Hazard Areas

• Jumbo-Jet-Size Transport Aircraft (Engine Thrusts: $25,000\,lbs$ to $105,000\,lbs$)

  • Ground-Idle Blast Danger Area: $1,100\,ft$ ($335\,m$).
  • Takeoff Thrust Blast Danger Area: $2,100\,ft$ ($640\,m$).
  • Inlet Hazard Area: $25\,ft$ radius (Idle) to $50\,ft$ radius (Takeoff).

• Medium-Size Jet Transport Aircraft (Engine Thrusts: $10,000\,lbs$ to $40,000\,lbs$)

  • Ground-Idle Blast Danger Area: $450\,ft$ ($137\,m$).
  • Takeoff Thrust Blast Danger Area: $1,200\,ft$ ($366\,m$).
  • Inlet Hazard Area: $15\,ft$ (Idle) to $25\,ft$ (Takeoff).

• Executive Jet Aircraft (Engine Thrusts: up to $10,000\,lbs$)

  • Ground-Idle Blast Danger Area: $200\,ft$ ($61\,m$).
  • Takeoff Thrust Blast Danger Area: $500\,ft$ ($152\,m$).
  • Inlet Hazard Area: $8\,ft$ (Idle) to $15\,ft$ (Takeoff).

• Helicopter Safety Protocols

  • Always approach and depart the aircraft in full view of the pilot.
  • Always enter and exit toward the front of the helicopter to avoid the tail rotor.
  • DANGER Area: Never go beyond the rear passenger door area (indicated in red on schematics).

Airworthiness Requirements and Training Principles

• Applicable Legislation

  • The primary Federal legislation governing workplace safety is the Work Health and Safety Act 2011.
  • Stakeholders bound by the Act include the Federal Government, State/Territory Governments, local authorities, employers, employees, and customers.

• Competency Based Training (CBT)

  • Definitions: CBT is an approach to vocational education and training focusing on what a person can do in the workplace after training.
  • Competency Standards: Industry-determined specifications comprising units of competency, elements, performance criteria, and evidence guides.
  • Skills Gap Formula: $\text{Skills Required} - \text{Current Skills} = \text{Skills Gap}$.
  • Levels of Supervision:
    • Direct Supervision: Shown every detail, every task checked.
    • Routine Supervision: Instruction and support provided as needed.
    • Limited Supervision: Minimal supervision; achievement of this level indicates competency.

• MEA Aeroskills Training Package (MEA19)

  • Covers Aviation Maintenance for civilian and Australian Defence Force (ADF) personnel (approx. 15,000 workers).
  • Unit Numbering System:
    • '1' = Common units (e.g., MEA154).
    • '2' = Avionics technical stream (e.g., MEA201).
    • '3' = Mechanical technical stream (e.g., MEA301).
    • '4' = Structures technical stream (e.g., MEA401).
    • '5' = Aircraft Life Support and Furnishing units (e.g., MEA501).

• Regulatory Bodies

  • ICAO (International Civil Aviation Organisation): UN agency acting as a global forum for civil aviation safety, security, environment, efficiency, continuity, and law.
  • CASA (Civil Aviation Safety Authority): Australia's independent statutory authority for safety regulation (established 6 July 1995).
  • Tripartite Industry Structure: CASA, the Department of Infrastructure, Transport, Regional Development and Local Government, and Airservices Australia.
  • CASA Hierarchy of Regulations: Civil Aviation Act 1998 $\rightarrow$ Civil Aviation Safety Regulations (CASR) $\rightarrow$ Manual of Standards (MOS) $\rightarrow$ Advisory Circulars (ACs).
  • CASR Part 66: Sets standards for AME (Aircraft Maintenance Engineer) licensing and AMS (Airworthiness Maintenance Scientist) certificates. Requires a minimum pass standard of $75\%$ in theory courses.

Work Health and Safety Regulations and Obligations

• Costs of Workplace Accidents

  • Direct costs: Personal injury, lost time, and lost production.
  • Hidden costs: Human anxiety/trauma, loss of morale, damaged product/equipment, idle machine time, training for replacements, rehabilitation, and loss of critical skills.

• Legal Definitions and PCBU

  • PCBU: Person Conducting a Business or Undertaking. Includes companies, sole traders, and partnerships. Holds the primary "Duty of Care."
  • Worker: Includes employees, contractors, sub-contractors, outworkers, apprentices, trainees, students on experience, and volunteers.
  • HSR: Health and Safety Representatives (replaces OHS representatives in NSW). HSRs can issue Provisional Improvement Notices (PINs) and direct unsafe work to cease.

• Manual Handling and Lifting Procedures

  • Manual Definition: Of, or done with the hands.
  • Procedure for Safe Lifting:
    1. Size up the load (weight and shape).
    2. Test the estimate by rocking gently.
    3. Position feet close for balance.
    4. Ensure a correct grip (diagonally opposite if possible).
    5. Keep a straight back (upper part erect and parallel to load).
    6. Tuck chin in; keep head erect.
    7. Lift with the legs (never the back); keep arms tucked in.
    8. Logic: If it is too big, use two people or mechanical equipment.

• Statutory Instruments

  • Act: Sets out broad responsibilities.
  • Regulations: Details how to implement sections of the Act.
  • Codes of Practice: Detailed guidance for specific trades or conditions.

Workplace Hazards and Hierarchy of Control

• Causes of Accidents

  • Inadequate knowledge: Performing duties without understanding equipment/materials.
  • Insufficient skill/training: Attempting activities beyond ability.
  • Improper attitudes: Inattention, impatience, and carelessness.
  • Unsafe acts: Neglecting precautions, skylarking, or making safety devices inoperative.

• Safety Committees

  • Mandatory for workplaces with over 20 employees. Functions include identifying hazards, promoing safe practices, and investigating incidents.

• Specific Environmental Hazards

  • Noise: Statutory limit is usually $85\,dB(A)$. Risk is present if you must raise your voice to talk to someone $1\,m$ away. Effects include Tinnitus (ringing in ears) and cumulative deafness.
  • Sunlight: Risk factors include Keratoses (rough spots), cataracts, and pterygial (tissue growth on eyes). SPF $15+$ broad-spectrum sunscreen should be applied $15\,minutes$ before exposure.
  • Skin Disorders: Contact Dermatitis (Irritant or Allergic). Common allergens include rubber additives (thiuram), nickel, and cobalt chloride.

• Hierarchy of Control Measures

  1. Elimination: Remove the hazard entirely (e.g., work at ground level to avoid falls).
  2. Substitution: Use a safer alternative (e.g., water-based paints instead of solvent-based).
  3. Isolation: Separate the hazard from people (e.g., concrete barriers).
  4. Engineering Controls: Physical mechanical devices (e.g., guards or trolleys).
  5. Administrative Controls: Systems of work (e.g., procedures, signage, or limiting exposure time).
  6. PPE: The last resort; relies on human behavior and supervision.

Personal Protective Equipment (PPE) and Safety Signage

• Poison Entry Routes

  • Inhalation: 90% of advanced composite entry; reaches blood stream rapidly via lungs.
  • Skin Absorption: 9% of entry; organic compounds pass through the skin.
  • Ingestion: 1% of entry; swallowing toxic dust with food or saliva.

• Exposure Limits

  • Peak Limitation: Maximum exposure for a very short duration.
  • Short-Term Exposure Limit (STEL): A $15\,minute$ limit; max 4 periods per 8-hour day with 1 hour between exposures.

• Safety Sign Colors

  • RED Circle with Diagonal Line: Prohibited acts (e.g., No Smoking).
  • BLUE Circle (Disc): Mandatory actions (e.g., Eye protection must be worn).
  • YELLOW Triangle with Black Border: Warning/Caution of non-life-threatening hazards.
  • GREEN Rectangle: Emergency information (e.g., Exit, First Aid kit).
  • RED Rectangle: Fire safety equipment location (e.g., Fire extinguisher).

• Dangerous Goods (Hazchem) Classes

  • Class 1: Explosives (detonators, fireworks).
  • Class 2: Gases (2.1 Flammable, 2.2 Non-flammable/Non-toxic, 2.3 Toxic).
  • Class 3: Flammable Liquids (Flash point $\le 60\,^{\circ}C$).
  • Class 4: Flammable Solids (4.1 Solids, 4.2 Spontaneous combustion, 4.3 Water-reactive).
  • Class 5: Oxidising Substances and Organic Peroxides.
  • Class 6: Toxic and Infectious Substances.
  • Class 7: Radioactive Materials (radium, X-ray equipment).
  • Class 8: Corrosives (acids, battery fluid).
  • Class 9: Miscellaneous (lithium batteries, dry ice, asbestos).

Aircraft Systems and Handling Precautions

• Primary Aircraft Systems

  • Propulsion, Flight Control, Fuel, Hydraulic, Electrical, Instrument, and Undercarriage.

• Power Sources

  • Hydraulic: System pressures up to $5,000\,psi$.
  • Pneumatic: Engine-driven compressors used for landing gear, brakes, and de-icing.
  • Electrical: 28V DC in light aircraft; 115V/400Hz AC in large commercial aircraft.
  • Bleed Air: Compressed air from gas turbine engines reaching temperatures of $230\,^{\circ}C$.

• Towing and Jacking

  • Towing: Use a tug/tractor with a tow bar. Personnel must be in the cockpit to operate brakes. Never exceed turning limits or use propellers to move the plane by hand.
  • Jacking: Ensure screw-type safety collars are used. One person required per jack. Ensure retraction tests are clear of obstructions.
  • Tie-down: Use gust locks or battens (lined with $1\,inch$ foam) to secure surfaces. Red streamers must be attached to indicate "Remove Before Flight."

• Engine Types

  • Reciprocating: Opposed (light aircraft) and Radial (heavy/historical).
  • Gas Turbine: Turbojet, Turbofan (most common), Turboprop (gearbox driven), and Turbo shaft (helicopters).

Specific Aviation Maintenance Hazards

• Propeller and Rotor Safety

  • Propeller Plane of Rotation: Marked by a $50\,mm$ RED strip on the fuselage.
  • Turbine Plane of Rotation: Marked by a $50\,mm$ RED strip; avoid during start-up.
  • Rotor Blade Hazards: Stay clear by a distance equal to the length of the aircraft. Blades droop at low revolutions.

• Oxygen Safety

  • Violent chemical reaction occurs if oxygen mixes with oil or grease. Do not use grease-contaminated tools on oxygen systems.
  • Maintain a $20\,m$ safety distance from flammable materials, vehicles, and GPUs during replenishment.
  • Earthing is mandatory before and during oxygen handling.

• Battery Safety

  • Thermal Runaway: A cycle where rising battery temperature reduces internal resistance, leading to more current and potential explosion.
  • Lead-acid (sulfuric acid) and Alkaline electrolytes must never be mixed.
  • Remove all jewelry (watches, rings) to prevent electrical burns from short-circuiting terminals.

• Aviation Fuels

  • AVGAS: 80 (Red), 100 (Green), 100LL (Blue).
  • AVTUR: Jet A (-$40\,^{\circ}C$), Jet A-1 (-$47\,^{\circ}C$), Jet B (-$50\,^{\circ}C$).
  • Bonding: Electrical bonding between plane and tanker is required to prevent static discharge sparks.

• Advanced Composites

  • Materials: Graphite, Kevlar, and Boron. Risks include airborne dust particles causing Asbestosis or Emphysema. Sanding must use approved dust extraction methods; never use compressed air to clean sanded surfaces.

• FOD (Foreign Object Damage)

  • Definition: Damage caused by objects inadvertently left in or on aircraft.
  • Control: Use Composite Tool Kits, FOD bags for fasteners, and clean clothing without small loose pockets.

Fire and Emergency Equipment

• Classes of Fire

  • Class A: Wood, Paper, Plastic (Water/Foam/Powder/Wet Chem).
  • Class B: Flammable Liquids (Foam/Powder/CO2).
  • Class C: Flammable Gases (Powder only).
  • Class D: Combustible Metals (Standard extinguishers ineffective).
  • Class E: Electrical Equipment (Powder/CO2).
  • Class F: Cooking Oils and Fats (Wet Chemical only).

• Extinguisher Identification

  • Water: Solid Red.
  • Foam: Blue Band.
  • Dry Powder: White Band.
  • Carbon Dioxide (CO2): Black Band.
  • Wet Chemical: Oatmeal Band.

• PASS Methodology for Use

  • P: Pull the pin.
  • A: Aim at the base of the fire.
  • S: Squeeze the handle.
  • S: Sweep side to side.

• Emergency Washing Facilities

  • Eye Wash: Flush for a minimum of $15\,minutes$. Discard bottles after any use.
  • Deluge Showers: Used for chemical splashes or clothing fires. Stay under for $15\,minutes$. Do not use high-flow deluge showers for eyes.

Question and Discussion Log

• Q: What is the primary role of ICAO?
  • A: It is a UN agency that acting as the global forum for civil aviation, working toward safe, secure, and sustainable development through cooperation among member states.
• Q: What comprises the CASA hierarchy of regulations?
  • A: The Civil Aviation Act 1998, Civil Aviation Safety Regulations (CASRs), Manual of Standards (MOS), and Advisory Circulars (ACs).
• Q: What is the difference between an Act and a Regulation?
  • A: The Act sets broad responsibilities, while Regulations provide the specific details and instructions for implementation.
• Q: What should you do if the SDS does not provide required information?
  • A: Contact the person or manufacturer listed in Section 1 of the document.
• Q: Why shouldn't you approach aircraft with hot brakes from the side?
  • A: Because overheated tires or wheels may explode, sending fragments sideways; approach from the front or rear only.