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Hair Adornments

Nickel Cadmium Batteries—Thermal Runaway

Jacking of Aircraft

Portable Electronic Devices



The procedures in AAP7001.059-TAREG support compliance with AAP7001.053-Technical Airworthiness Regulations, which have been superseded.

Procedures supporting compliance with AAP8000.011-Defence Aviation Safety Regulations are contained in AAP 7001.059-TRANSITION

An organisation’s exposition details which 059 version is applicable


1. Workplace health and safety is addressed in Section 8 Chapter 3 - Work Health and Safety.

2. This chapter is intended as a consolidated reference to relevant orders, instructions and publications that deal with common hazards and also prescribes some precautions to be observed at Approved Maintenance Organisations (AMOs).


3. AMOs must ensure all safety precautions detailed in aircraft and aeronautical product authorised maintenance data are adhered to.


4. The following references are given as a guide and must be used in conjunction with other relevant policy instructions:

  1. Management of Hazardous Materials. Refer WHS Manual Vol 2 Part 3A Chap 1 - Hazardous Chemicals Management.
  2. Personal Protective Equipment. Refer WHS Manual Vol 2 Part 4 Chap 3 - Personal Protective Equipment.
  3. Earthing of Aircraft. Refer AAP 7045.002-1(AM1) - ADF Aircraft Wiring and Bonding Manual.
  4. Radar and Radio Transmitter Testing. Refer Defence Radiation Safety Manual.
  5. Radioactive Material. Refer Defence Radiation Safety Manual.
  6. Working at Heights. Refer WHS Manual Vol 2 Part 3B Chap 3 - Slips, Trips and Falls.
  7. Confined Space Entry. Refer WHS Manual Vol 2 Part 3B Chap 2 - Working in Confined Spaces.
  8. Working Within Aircraft Fuel Tanks. Refer AAP 7029.007-3M - Aircraft Fuel Cells and Internal/External Tanks
  9. Asbestos and Ceramic Fibre. Refer WHS Manual Vol 2 Part 3 Chap 5 - Asbestos Management, Defence WHS Technical Fact Sheet #17 - Asbestos.
  10. Electrical Equipment and Circuits. Refer WHS Manual Vol 2 Part 3B Chap 4 - Electrical safety.
  11. Tripped Circuit Breakers or Ruptured Fuses. Refer AAP 7090.001-99 - Avionics Engineering General Instructions Instruction 14.
  12. Beryllium. Refer Defence WHS Technical Fact Sheet #20 - Beryllium, ABR 5225 Vol 1 Chap 6 Annex K - Safe Handling of Beryllium Substances.
  13. Cadmium. Refer Defence WHS Technical Fact Sheet #4 - Cadmium, DI(N) LOG 59-1-Cadmium–Restrictions and Precautions.
  14. Oxygen-Precautions. Refer AAP 7002.023(AM1)—Dry Breathing Oxygen Technical Requirements and General Information and AAP 7055.001-99(AM1) - Liquid and Gaseous Dry Breathing Oxygen Maintenance Instructions.
  15. Fire and Safety Precautions. Refer WHS Manual Vol 2 Part 2 Chap 1 - Miscellaneous Workplace Safety Hazards.
  16. Safe Use and Handling of Composite Materials. Refer WHS Manual Vol 2 Part 3A Chap 1 - Hazardous Chemicals Management and AAP 6734.001-Defence Aviation Safety Manual Chapter 10-Emergency Response.
  17. Aviation Fuels-Aircraft on Air Capable Ships. Refer DEF(AUST)5695B-Petroleum, Oils and Lubricants Manual Part 2 Section 1 Chapter 5-Navy Aviation Fuel Management and ABR 5419 Vol 1 Chapter 9-Helicopter Fuelling and Defuelling.
  18. Fuel Spillage. Refer DEF(AUST)5695B Part 1 Section 2 Chapter 2 - Generic Hazard Controls and Precautions.
  19. Military Aviation Turbine Fuels. Refer Defence WHS Technical Fact Sheet # 28 - Exposure to Military Aviation Turbine Fuels in Defence.
  20. Isocyanates. Refer Defence WHS Technical Fact Sheet #7 - Isocyanates.


5. Jewellery (except dog tags secured inside the working dress) must not be worn when performing maintenance on aircraft or aeronautical product. Watches (preferably with a non-metallic wristband) are permitted, except when performing maintenance on, or in the vicinity of canopies, flight controls, or electrical systems.


At the discretion of the SMM or delegate, jewellery restrictions may be relaxed where the potential to induce foreign object hazards or injury to personnel is unlikely or improbable.

Hair Adornments

6. Maintenance personnel may find it necessary to raise or restrain their hair whilst carrying out maintenance on aircraft or aeronautical product in an aviation maintenance environment in order to remove the potential hazard posed by unrestrained hair. Hair is to be formed into a plait/ponytail and secured neatly with an elastic style band in such a manner that its length does not pose a hazard for that particular working environment. Alternatively, the hair may be restrained with a full covering hairnet. At no time are hair fasteners of a metal or plastic type to be used as a restraint as they constitute a foreign object hazard.

Nickel Cadmium Batteries-Thermal Runaway

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Thermal runaway in nickel cadmium batteries can CAUSE an EXPLOSION which could result in death or injury to personnel.

Do not use a CO2 extinguisher to extinguish or cool the battery if flames are not present, as the static discharge from the fire extinguisher nozzle can ignite any explosive gases present. If the battery is on fire and flames are present, a CO2 fire extinguisher may be used to extinguish the fire.

7. Thermal runaway is a regenerative process of heat build–up that can occur in Nickel Cadmium (NiCad) battery/cells, which are subjected to overcharging. Thermal runaway may also result from cell breakdown, where the negative and positive plates make contact with one another and create a ‘hot spot’ which can increase current flow within the batteries and can progressively damage neighbouring cells. Thermal runaway is normally associated with battery/cell charging but may occur with installed batteries.

8. Repeated attempts to start an engine using internal batteries are to be avoided when the ambient temperature is above 300C. Peak current demands significantly increase cell temperatures, and high charging voltages will increase the likelihood of thermal runaway. A period of time is to be allowed after an aborted start to allow the battery to cool.

9. A battery or cell in thermal runaway will exhibit: white fumes (potassium hydroxide), acrid smell, electrolyte boiling and spillage, a fall in cell voltage and/or excessively high battery/cell temperature. A possibility exists that the battery or cell may totally destruct.

10. A potential hazard exists to personnel and equipment from the spewing of hot electrolyte and explosive gases, therefore, installed batteries that exhibit thermal runaway symptoms or which are found in an excessively overheated condition are to be stabilised and handled as follows:

  1. Isolate electrical power at the battery switch and at battery circuit breakers. Do not electrically disconnect the battery until stable and the area has been ventilated, as a spark may ignite explosive gases present.
  2. Ventilate the battery compartment to reduce the battery temperature and dissipate gases. Only if the battery temperature is excessively high may in-situ battery cooling be applied using water mist/spray (fog). In this instance, consideration is to be given to the potential hazard to personnel from battery self destruction, the minimum PPE required are approved full face shield, approved working dress with sleeves rolled down, safety boots, full length rubber or plastic apron and long rubber gloves. The water mist/spray (fog) is to be applied directly to the battery casing until cool to touch.
  3. To ensure the battery remains in a stable state, do not attempt to handle or remove the battery for at least 30 minutes.
  4. Remove all traces of electrolyte from the battery, battery compartment and adjacent areas by flushing with clean fresh water, allow to dry and repeat if necessary. Prior to installing a replacement battery, treat any damage or corrosion in accordance with the aircraft maintenance manual.

Jacking of Aircraft

11. Unless carefully controlled, damage to aircraft and injury to personnel can easily occur during jacking operations. All aircraft jacking operations are to be supervised and performed by authorised personnel.

12. In addition to the procedures outlined in the aircraft authorised maintenance data, personnel supervising the jacking operation are to:

  1. Before Jacking:
    1. Ensure the jacking equipment is serviceable, correctly positioned and secured in accordance with the relevant aircraft publication.
    2. Brief all personnel involved with the jacking operation and ensure they are competent to operate the jacking equipment.
    3. Ensure any ground support equipment, eg hydraulic rig, is not connected to the aircraft whilst jacking.
    4. Ensure the appropriate notices ‘DANGER – AIRCRAFT ON JACKS’, are placed in prominent positions around the aircraft.
  2. During Jacking:
    1. Ensure the aircraft is being raised evenly and within the aircraft pitch and roll limitations.
    2. Check the required clearances remain available.
    3. Ensure personnel not involved in the jacking operation remain clear of the aircraft.
  3. Before Lowering:
    1. Brief all personnel involved with the jacking operation and ensuring they are competent to operate the jacking equipment.
    2. Ensure any ground support equipment, eg hydraulic rig, is not connected to the aircraft whilst lowering.
  4. On Completion:
    1. Ensure that the jacks are removed from beneath the aircraft as soon as the weight of the aircraft is off the jacks.
    2. Ensure all ground support equipment and warning signs are returned to the appropriate storage area.

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      Jacking of aircraft on air capable ships is only to be conducted in exceptional operational circumstances.

13. Jacking of Aircraft on Air Capable Ships. The jacking of aircraft on air capable ships is a potentially dangerous operation which is not to be undertaken without due consideration of the operational necessity and the prevailing weather conditions. If possible this requirement is to be deferred until the ship is alongside or at anchor.

14. If a jacking operation is necessary whilst at sea, permission is to be obtained from the Ship’s Commanding Officer prior to jacking the aircraft.

15. Individual jacks are to be lashed securely to the deck independent of the aircraft lashings.

16. Sufficient aircraft lashings are to be fitted to the aircraft and adjusted as necessary during the entire jacking operation. Care is to be taken that the adjustment of the lashings does not oppose the action of the jacks. Only those personnel required for the jacking operation are to be in the immediate vicinity of the aircraft.

Portable Electronic Devices

17. The use of cordless/mobile telephones (including in ‘STANDBY’ mode) is prohibited in any maintenance environment unless specifically authorised by the SMM or delegate.

18. The carriage and/or operation of Portable Electronic Devices (PEDs) in ADF aircraft is defined in AAP 7001.054-Electronic Airworthiness Design Requirements Manual Section 5 Chapter 6 - Role Equipment and Portable Electronic Devices and may require responsible SPO approval.

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