Module 7 (Maintenance Practices) Sub Module 7.1 (Safety Precautions-Aircraft and Workshop).pdf

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Module 7 – MAINTENANCE PRACTICES

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MODULE 7: MAINTENANCE PRACTICES Sub Module 7.1 - SAFETY PRECAUTIONS – AIRCRAFT AND WORKSHOP Sub Module 7.2 - WORKSHOP PRACTICES Sub Module 7.3 – TOOLS Sub Module 7.4 – AVIONIC GENERAL TEST EQUIPMENT Sub Module 7.5 – ENGINEERING DRAWINGS, DIAGRAMS & STANDARDS Sub Module 7.6 – FITS AND CLEARANCES Sub Module 7.7 – ELECTRICAL WIRING INTERCONNECTION SYSTEM (EWIS) Sub Module 7.8 – RIVETING Sub Module 7.9 – PIPES AND HOSES Sub Module 7.10 – SPRINGS Sub Module 7.11 – BEARINGS Sub Module 7.12 – TRANSMISSIONS Sub Module 7.13 – CONTROL CABLES Sub Module 7.14 – MATERIAL HANDLING Sub Module 7.15 – WELDING, BRAZING, SOLDERING AND BONDING Sub Module 7.16 – AIRCRAFT WEIGHT AND BALANCE Sub Module 7.17 – AIRCRAFT HANDLING AND STORAGE Sub Module 7.18 – DISASSEMBLY, INSPECTION, REPAIR AND ASSEMBLY Sub Module 7.19 – ABNORMAL EVENTS Sub Module 7.20 – MAINTENANCE PROCEDURES

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Module 7 – MAINTENANCE PRACTICES

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Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

List of Amendments Amendment No.

Sub-Module & Pages:

Issue Date:

Issue 01, Rev-00

All

31 March 2014

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Date Inserted:

Inserted By:

Date Removed:

Removed By:

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Module 7 – MAINTENANCE PRACTICES

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Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

MODULE 7 Sub Module 7.1

SAFETY PRECAUTIONS – AIRCRAFT AND WORKSHOP

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Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

Contents INTRODUCTION ...................................................................... 1 GENERAL SAFETY PRECAUTIONS ....................................... 1 SAFETY WITH ELECTRICITY .................................................. 3 SAFETY WITH GASES............................................................. 6 SAFETY WITH OXYGEN .......................................................... 9 SAFETY WITH OIL AND CHEMICALS ................................... 13 SAFETY WITH FIRE ............................................................... 20 PRINCIPLES OF EXTINGUISHING FIRES ............................ 26 INSTRUCTIONS INCASE OF FIRE ........................................ 32

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Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

GENERAL SAFETY PRECAUTIONS INTRODUCTION Most accidents are, in the main, caused by human carelessness and accidents in the work place are among the main causes of death and disability. They are, additionally, the cause of a great loss of man-hours and, thus, cost companies (and individuals) large amounts of money. All personnel should be aware, not only of the potential for accidents and injury, wherever they work, but also of the legislation and information that is available in an attempt to prevent accidents actually happening. While it is incumbent upon companies, to ensure that all personnel receive adequate training in Health and Safety matters, this Module contains a reminder of some of the general safety precautions which are necessary, when working in the aerospace industry. The Module continues with further topics, which are concerned with the practices recommended for the safe and efficient maintenance of aircraft and aerospace components.

ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 1

Aircraft, by their very nature and design, make for a dangerous working environment. The danger is further increased by the wide variety of machines, tools and materials required to support and maintain aircraft. 

Technicians should only operate equipment with which they are familiar and can operate safely.



Hand tools should be kept in proper working order.

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Technicians should know the location of the first aid box and emergency equipment.

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Good housekeeping in hangars, shops, and on the flight line is essential to safe and efficient maintenance. The highest standards of orderly work arrangements and cleanliness should be observed while maintaining an aircraft. When a maintenance task is complete, the technician should remove and properly store maintenance stands, hoses, electrical cords, hoists, crates, boxes, and anything else used to perform the work.



Pedestrian lanes and fire lanes should be marked and used as a safety measure to prevent accidents and to keep pedestrian traffic out of work areas.

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Power cords and air hoses should be straightened, coiled, and properly stored when not in use.

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Oil, grease, and other substances spilled on hangar or shop floors should be immediately cleaned or covered with an absorbent material to prevent fire or personal injury.

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Under no circumstances should oil or cleaning fluid be emptied into floor drains. Fumes from this type of disposal may ignite and cause severe property damage.

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Gasoline spills on the hangar floor should be flushed away with water. Sweeping these fuel spills with a dry broom could cause static electricity that might ignite the fuel.

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Aircraft finishes should be applied in a controlled environment (paint room) whenever possible. A technician should never do this type of work near an open flame or in the presence of lights that are not explosion proof. No other work should be done on an aircraft while it is being painted.



Never use unstable piles of boxes, inadequate scaffolding, or un-secured ladders for working at heights. Always use designated ladders, work stands, maintenance steps that are equipped with appropriate handholds, handrails and safety railing.



Always walk and never run, and never hurry when engaged in hazardous work.

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Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

It is very important, that all personnel know the location of the fixed points where firefighting equipment and First Aid treatment are available. They must also be aware of the types of emergency that can occur in the workplace (whether in the workshop, hangar or on the ramp), and of the procedures to be followed in any emergency.

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Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

SAFETY WITH ELECTRICITY The human body conducts electricity. Furthermore, electrical current, passing through the body, disrupts the nervous system and causes burns at the entry and exit points. The current, used in domestic 220-240 volt, 50Hz ac electricity, is particularly dangerous because it affects nerves in such a way that a person, holding a current-carrying conductor, is unable to release it. Table 1 shows some typical harmful values and effects of both ac and dc electricity supplies. Since water also conducts electricity, great care must be taken to avoid handling electrical equipment of all kinds when standing on a wet surface or when wearing wet shoes. The water provides a path to earth and heightens the possibility of electric shock. To ensure that equipment is safe, the minimum requirement is through the use of three-core cable (which includes an earth lead) and, possibly, a safety cut-out device. In conjunction, more often than not, with ignorance or carelessness, electrical hazards generally arise due to one or more of the following factors:  Inadequate or non-existent earthing  Worn or damaged wiring, insulation, plugs, sockets and

All electrical equipment must be regularly checked and tested for correct operation and electrical safety. To show that this has been done, a dated label should be attached, showing when the equipment was last tested and when the next inspection is due. Any new item of equipment must have a test label attached. The presence of a test label does not, however, absolve the user from checking the equipment for any external signs of damage, such as a frayed power cord (or missing safety devices) before use. In the event of a person witnessing another person receiving an electric shock, the basic actions, to be followed by the witness, are:  Shout for help and ensure there is no danger of also becoming a victim  Switch off the electrical current or remove the victim from the supply by means of insulated material  If the victim has ceased breathing, initiate resuscitation  Call for professional medical help  If the victim is suffering from burns, exclude air from wounds  Treat for shock by keeping the victim warm

other installations  Bad wiring systems and the misuse of good systems  Incorrect use of fuses  Inadequate inspection and maintenance of power tools

and equipment The approved methods of artificial resuscitation must, by law, be displayed on wall charts in workplaces.

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Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

Voltage/Current

Possible Outcome

50V ac or 100V dc

May give rise to dangerous shocks

1 mA

Harmless tingle

1 – 12 mA

Painful, but can be released

12 – 20 mA

Very painful, cannot be released

20 – 50 mA

Paralysis of respiration

> 50 mA

Heart stoppage

to be aware of the safety procedures associated with its use. Single phase supply Most shop equipment operating on 110/230-volt single-phase alternating current is connected with a three-conductor cord. Of the three conductors one wire carries the power and is referred to as the 'Live' wire. The second wire is the 'Neutral' and is connected to the earth ground where the power enters the building or at the transformer. The third wire is the ‘Earth’ equipment ground and connects the housing of the equipment to the earth ground. Single phase wire/connector identification Live Wire - The live wire is connected to the righthand connector of the 'Plug Base'. Neutral Wire - The neutral wire is connected to the lefthand connector of the 'Plug Base' Earth Wire - Earth wire is connected to the larger sized top center connector of the 'Plug Base'

Workshop electrical supply Every shop in which aircraft maintenance is performed depends upon electrical power for its operation, and it is the responsibility of every one that uses electrical power ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 4

The following table is a guide to different wire insulation color combinations available for the above wires.

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Module 7 – MAINTENANCE PRACTICES

Insulator Color 220V/240V

110V/120V

Live

Red

Brown

Black

Neutral

Black

Blue

White

Earth

Green

Green/Yellow

Green

Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

Safety issued regarding 3 phase supply is the same as for the single phase supply, the only difference being that a failure in one phase will result in isolation of power for all phases provided that proper protective equipment (such as 3 phase circuit breakers) are installed.

110v Single-phase Plug Top

Three phase supply Three phase power supply may be available in certain workshop to operate machinery that requires more power than could be afforded by a single-phase supply or to repair and test aircraft equipment. 3-phase outlet is different in design to the single-phase outlet and will accept only compatible connectors. ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 5

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Module 7 – MAINTENANCE PRACTICES

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Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

Path of an electrical circuit

SAFETY WITH GASES

Aircraft maintenance personnel are required to work with some form of gas at one time or another. Therefore a knowledge of the hazards involved and the safety precautions to be taken when working with such gases is mandatory. Here the discussion will be on: ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 6

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Compressed Air – Compressed air is primarily used as a power source for maintenance equipment and tools In addition compressed air is also used for painting, as a pressure source for carrying out leak checks, for purging of blocked plumbing, etc. Oxygen – Oxygen is available in the compressed form as Industrial Oxygen and Breathing oxygen. Industrial Oxygen is primarily used for oxy-acetylene welding Breathing Oxygen is used in the crew emergency oxygen system. On some aircraft, breathing Oxygen is also used in the passenger emergency oxygen system. Nitrogen – Used to inflate aircraft wheel assemblies, pre-charge accumulators, as a pressure source for testing of certain equipment and systems and as a propellant. Other gases – Gases such as Argon, Acetylene, Carbon Dioxide, etc. have limited application in the aviation industry. Argon and Acetylene is used in welding, CO2 as a fire extinguishing agent and as a propellant.

Compressed gas safety Compressed gases are frequently used in the maintenance and servicing of aircraft. Most shop compressed air is held in the tanks and lines under a pressure of about 100psi. The use of compressed gases requires a special set of safety measures. The following rules apply for the use of compressed gases: 

Handle cylinders of compressed gases as you would

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Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

high- energy sources and therefore potential explosives. 

Always use safety eye-shields when handling and using compressed gases.



If a concentrated stream of compressed air is blown across a cut in the skin, it is possible for air to enter the bloodstream and cause severe injury. For this reason, air-dusting guns are usually equipped with a restrictor that reduces the pressure at their discharge to 30psi or less.



Be very careful when using compressed air that you do not blow dirt or chips into the face of anyone standing near by

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Do not use compressed air to clean hands or clothing as pressure can force debris into the flesh leading to infection.



Never use a cylinder that cannot be positively identified of its contents.

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When storing or moving a cylinder, have the cap securely in place to protect the valve stem.

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When large cylinders are moved, strap them to a properly designed wheeled cart to ensure stability.

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Use the appropriate regulator on each gas cylinder. Adapters or homemade modifications can be dangerous. For Training Purpose Only Rev. 00 Mar 2014

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

Do not use compressed gas or compressed air to blow away dust or dirt, since the resultant flying particles are dangerous.

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Release compressed gas slowly; the rapid release of a compressed gas will cause an unsecured gas hose to whip dangerously and also may build up a static charge, which could ignite a combustible gas.

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Inspect air hoses regularly for breaks and worn spots and replace unsafe hoses immediately.

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All connections should be kept in a “no leak condition”

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Inline oilers, if installed, should be maintained in operating conditions.

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The system should have water sumps/traps installed and these should be drained regularly.

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Air hoses should be straightened, coiled, and properly stowed when not in use.

Sub Module 7.1 – Safety Precautions – Aircraft and Workshop



Securing the gas cylinder’s valve, disconnecting and removing associated distribution equipment.



Shutting the cylinder’s valve, disconnecting removing associated distribution equipment.



A requirement that only properly trained personnel are permitted to move cylinders.



Use properly designed lifting equipment movement of larger gas cylinders.

for

and

the

Moving cylinders The majority of accidents involving gas cylinders occur while moving them from one location to another. The following control measures should be used to reduce the potential for an accident: 

The use of purpose-built trolleys or other suitable devices for gas cylinder transportation.

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Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

intensity in Oxygen-rich atmosphere. In addition, oxygen combines with oil, grease, or bituminous material to form a highly explosive mixture, which is sensitive to impact. Physical damage to, or failure of, Oxygen containers, valves, or plumbing can result in explosive rupture, with danger to life and property. It is imperative that the highest standard of housekeeping is observed in handling oxygen and that only authorized persons are permitted to service aircraft. In addition to aggravating the fire hazard, liquid oxygen will cause severe "burns" (frostbite) if it comes in contact with the skin because of its low temperature. (Oxygen boils at 297° F.)

Fig. A – Compressed Gas Bottle with safety Cap fitted

SAFETY WITH OXYGEN Oxygen is a colorless, tasteless, and odorless gas. Gaseous oxygen is chemically stable and is non-flammable; however, combustible materials ignite more rapidly and burn with greater ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 9

Oxygen is often found in aviation maintenance shops stored in steel cylinders under a pressure of around 2,000psi. These cylinders have brass valves screwed into them, and if a cylinder should be knocked over and the valve knocked off, the escaping high-pressure gas will propel the tank like a rocket. Be sure that all gas cylinders are properly supported, and that the cap is screwed securely on any tank that is not connected into a system to protect the valve from damage.

Oxygen must never be allowed to come in contact with petroleum products such as oil or grease as oxygen will cause the oil to ignite spontaneously and burn. Never use an oily rag or tools that are oily or greasy to install a fitting or a regulator on an oxygen cylinder. For Training Purpose Only Rev. 00 Mar 2014

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Only oxygen marked "Aviators Breathing Oxygen" which meets Federal Specification BB-O-925a.Grade A or equivalent may be used in aircraft breathing oxygen systems. Before servicing any aircraft, consult the specific aircraft maintenance manual to determine the proper type of servicing equipment to be used. Two persons are required to service an aircraft with gaseous oxygen. One man should be stationed at the control valves of the servicing equipment and one man stationed where he can observe the pressure in the aircraft system. Communication between the two men is required in case of an emergency. Aircraft should not be serviced with oxygen during refueling, defueling, or other maintenance work, which could provide a source of ignition. Oxygen servicing of aircraft should be accomplished outside hangars.

Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

pre-charge the potable water tank in aircraft equipped with potable water system in case of normal pressure supply failure. Nitrogen is usually supplied in compressed gaseous form in steel cylinders pressurized up to 2500psi. Nitrogen is also supplied as liquid Nitrogen in cryogenic cylinders that is to be installed in special Nitrogen carts that convert liquid Nitrogen to gaseous form for supply. Nitrogen is used in place of compressed air mainly due to two reasons. a. Nitrogen is much cleaner than compressed air drawn from pneumatic system or a cart as it does not contain moisture or lubricants such as oil. b. Nitrogen is benign to most materials and reduces the fire hazard especially at elevated temperatures. This is the main reason why Nitrogen is used for charging aircraft tires. An important hazards associated with Nitrogen is that it tends to displace Oxygen (in an enclosed area) resulting in asphyxiation. It also causes frostbites if it comes in contact with the skin.

Nitrogen and other gases Nitrogen is a colorless, tasteless, odorless gas that is widely used in the aviation industry as a compressed gas for pre- charging all types of accumulators, pneumatic reservoirs of standby systems and most importantly for inflating aircraft tires. Nitrogen is also used to ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 10

Carbon Dioxide, Argon, Acetylene are some of the other gases that have various application in the aviation industry. Carbon Dioxide is supplied in compressed form stored in steel or aluminum cylinders and is used for inflating passenger life jackets and Slide/Rafts. For Training Purpose Only Rev. 00 Mar 2014

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Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

Argon is used as the blanket medium in Tungsten Inert Gas (TIG) Welding. Argon is used for this purpose as it is an inert gas and does not react with any substance even at such high temperatures.

The format of these sheets must be consistent with the requirements of the Hazard Communications Standard. MSDSs should be provided by the manufacturer for each hazardous material supplied by them.

Nitrogen and Argon are not toxic to humans but may displace air if released in large quantities in to a poorly ventilated enclosure.

The Material Safety Data Sheet is the primary source of information about hazardous chemicals used in your work site. Your employer is required to have an MSDS for every hazardous chemical used or stored at your work site, and to make it available for review on request.

Acetylene gas is a flammable, colorless gas that has a distinctive, disagreeable odor, readily detectable even when heavily diluted with air. Acetylene is used as the fuel that is combined with Oxygen in oxyacetylene welding. Acetylene is stable under low pressures and normal temperatures but becomes dangerously unstable when compressed to a pressure greater than 15psi. Acetylene is therefore supplied in cylinders containing asbestos and charcoal that is saturated with acetone. Since acetone is capable of absorbing approximately 25 times its own volume of Acetylene gas, this mixture can be pressurized up to 250psi.

Material Safety Data Sheets repeat the hazard information required on a product's label, however, MSDSs are also required to specify other information such as emergency and clean-up procedures, chemical names, and a phone number for the manufacturer or importer. The arrangement of information on the MSDSs may vary from manufacturer to manufacturer, but all MSDS' must contain the eight basic elements described on the following screens.

When working with acetylene gas, take necessary precaution as with a highly combustible gas and also ensure proper ventilation to prevent displacement of air in an enclosure. Material safety data sheets

Material safety data sheet data

A material safety data sheet (MSDS) is a document provided by the material manufacturer or subsequent material processor that contains information related to the material hazard and includes safe handling and disposal procedures.

A Material Safety Data Sheet is divided into nine (9) sections.

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Section I – Product Identification: Section I lists information used by the manufacturer to identify the following: For Training Purpose Only Rev. 00 Mar 2014

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

Manufacturer’s name, address, contact number and Emergency contact number



Chemical name, Trade name, Chemical family, formula

Section II – Hazardous Ingredients: Section II describes the various hazardous ingredients contained in the product that are more than 1 percent (1%) of the total, their percentages, and exposure limits. Section III – Physical Data: Section III includes such important physical properties as follows; Boiling point, Specific gravity, Vapor pressure, Percent volatile, Vapor density, Evaporation rate, Solubility in water, Appearance and odor.

Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

Section VII – Spill Leak and Disposal Procedures: Section VII lists the procedures, in a general sense, that are to be followed in case of an accidental spill or release. The procedure normally includes information regarding containment, evacuation procedures, and disposal. Section VIII – Special Protection: The required special safety equipment when using the material is included in Section VIII. The need for such equipment is dependent upon the exposure incurred when using the material and the duration of use. Section IX – Special Precautions: Special handling and storage information are listed in the section IX.

Section IV – Fire and Explosive Data: Section IV describes the nature of the fire and explosion hazard data. Based upon the flash point and other fire and explosive data, the appropriate extinguishing agent for fires involving each material is listed. Section V – Reactivity Data: Section V describes the ability of the material to react and release energy or heat under specific conditions. Section VI - Health Hazard Information: Known health hazards for the material are described in this section. Information is also available to assist the user and the medical personnel to identify overexposure and if so, the material involved, active ingredient and known antidote. Emergency and First Aid procedures for ingestion, skin contact, and eye contact. ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 12

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SAFETY WITH OIL AND CHEMICALS ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 13

Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

The aviation maintenance technician frequently must work in potentially dangerous environments. In many cases, particularly when dealing with hazardous materials, the technician may not easily recognize those hazards. Some of these dangerous environments may be caused directly by the materials with which the aviation maintenance technician must work. In For Training Purpose Only Rev. 00 Mar 2014

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addition, exposures may be caused by other activities occurring in the area that are not directly related to the technician's activities. Hazardous materials are typically grouped into three categories: 

Chemical agents



Physical hazards



Biological hazards

Chemical agents A wide variety of oils and chemicals are used in the aviation industry. Oils are mainly used as lubricants and hydraulic fluids. Chemicals refer to myriad of categories from detergents to sealants. Almost every process in aviation maintenance has some involvement with at least one chemical. Therefore, it is impossible to give detailed safety practices associated with their use. Always refer the appropriate manuals (especially chemical manufacturers’ manuals) for correct method of use and necessary precautions to take.

Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

4. Reactive Flammable and reactive chemicals become hazardous primarily after some outside event, condition, or substance interacts with them. For example, the necessary components for a fire to occur are fuel, oxygen, and heat. In that relationship, flammables are the fuel, and heat and oxygen are the outside agents. Reactive material when combined with certain other materials, are capable of generating heat and/or gases, causing an explosion. Corrosives and toxins on the other hand, act directly on the human body when exposure occurs. Exposing the skin, eyes, and other mucous membranes (such as the nose) to these elements can cause varying degrees of harm. Toxic agents cause poisoning. Aviation maintenance technicians should be particularly concerned when using toxic agents, because the ultimate effects of toxic poisoning are frequently delayed. It may take weeks, months, or even years for the poisoning to become apparent; because the toxic materials are capable of using the bloodstream to move through the body, the cause-and-effect relationship may not be easily recognized. Flammables (and combustibles)

Chemicals are categorized into four classes based on their properties.

2. Corrosive

Flammables are materials that may easily ignite in the presence of a catalyst such as heat, sparks, or flame. They may be in any of the three physical forms: solid, liquid, or gas. Combustible liquids are very similar to flammable liquids, but they are not as easy to ignite.

3. Toxic

Frequently found flammable or combustible materials in the

1. Flammable

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Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

aviation industry include fuels, paint-related products, alcohols, acetone, toluene, and some metal filings.



Attempt to close shutoff valve(s).

Generally recommended personal safety equipment



Remove container(s) from the area.



For large spills, leave the area immediately and notify your supervisor.



In case of direct contact with skin or eyes, rinse immediately with water.



Fire-retardant clothing



Fire extinguisher

Handling and Storage 

Limit access to open flames, sparks, hot surfaces, etc.



If toxic substances are inhaled, go to a fresh-air area.



Note: Static electricity may produce sparks. To avoid sparks, containers should be grounded.



If contact is made through clothing, remove wet clothing and store it in a proper container.



Limit quantities to the minimum needed to accomplish the desired task.



Do not attempt compressed air.



Store the materials in approved containers only and in designated areas only

to

remove

the

substance

with

Corrosives 

Store flammable toxins and corrosive toxic materials separately. The corrosive gases could attack the flammable containers, eventually leading to a leak of flammable materials.

Typical emergency procedures 

Turn off electrical equipment or any other potential source of sparks.

ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 15

Corrosive materials are materials that can react with metallic surfaces and/or cause bumming of the skin. Frequently found corrosives in the aviation industry include acids and bases, such as battery acids and metal cleaning solutions. Strong acids are most normally found in a liquid form, whereas bases tend to come in powdered form. Generally recommended personal safety equipment For Training Purpose Only Rev. 00 Mar 2014

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

Gloves, aprons, respirator, face shield or goggles, and, sometimes, protective footwear.

Handling and Storage 

Containers must be corrosive resistant.



Eye (goggles and/or faces shields) and skin protection (such as gloves) should always be worn.



Never add water to acid.



Acids and bases should be stored separately.



Eye washes and showers should be easily accessible to the work area.



Flammable toxins and corrosive toxic materials should be stored separately. The corrosive gases could attack the flammable containers, eventually leading to a leak of flammable materials.

Typical emergency procedures 

Remove any corrosives that have come in contact with your skin or eyes by rinsing with fresh water (approximately 15 minutes).

Sub Module 7.1 – Safety Precautions – Aircraft and Workshop



Check safety equipment before attempting to stop the flow of spillage by creating a darn.

If swallowed, DO NOT INDUCES VOMITING. Drink large amounts of water. Seek medical attention immediately. Toxins Toxins are generally defined as any substance that can cause an illness or injury .The effects of toxins may appear all at once, (called acute effects) or may build up over time with additional exposure (chronic effects). Some toxins may dissipate over time when further exposure is eliminated, while others remain in a human's system, even after death.

Frequently found toxins in the aviation industry may be grouped into eight categories. 1

Solvents and thinners, paints, ketones, and adhesives.



Remove any contaminated clothing-

2

Solids such as metal dust or asbestos.



Go to an area with fresh air.

3

Machine lubricants, cutting fluids, and oils.



Ventilate the area.

4

Gases such as carbon dioxide or nitrogen

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Polymers, epoxies, and plastics. Although not normally toxic in their final form, these materials posses toxic properties during the fabrication process. Sensitizers, such as epoxy systems. Such materials react with and may destroy portions of the body's immune system. The effects of sensitizers may be cumulative, so minimal levels of exposure are recommended.

8

Carcinogens. Carcinogens may cause changes in the genetic makeup of a human cell, resulting in cancer.

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Reproductive hazards, such as carcinogens. These hazards are rare in the aviation industry. Such materials may either interfere with the reproductive process or affect the developing process of the fetus.

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

Minimize the release of toxic agents into the environment by capping all containers and storing them in properly ventilated areas. When toxins are used in open containers, such as dip tanks and trays, their surface areas should be kept to a minimum in order to reduce the rate of evaporation into the surrounding environment.



Flammable toxins and corrosive toxic materials should be stored separately. The corrosive gases could attack the flammable containers, eventually leading to a leak of flammable materials.

Typical emergency procedures Generally recommended personal safety equipment 

Gloves, aprons, respirator, face shield or goggles, and, sometimes, protective footwear are recommended.



Be sure to use the environmental control systems that may already be in place, such as ventilation fans and filters.

Handling and Storage ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 17



If there is any doubt in your mind regarding the degree of toxicity of the substance spilled, LEAVE THE AREA IMMEDIATELY AND NOTIFY YOUR SUPERVISOR.



Generally speaking, if the spillage is less than 1 gal, it may be cleaned up by wiping it up with absorbent materials.

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Reactive agents are those materials that react violently with other materials (not necessarily solids). The reactions that may take place range from violent explosions to the emission of heat and/or gases.

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

Be sure to use the environmental-control systems. Handling and Storage



Store reactive materials in a location separate from other materials. Always review the MSDS (material safety data sheet) for incompatible materials.



Many reactive agents are both toxic and corrosive.

The following reactive agents are frequently found in the aviation industry: Oxidizers, which add oxygen to situations where high levels of heat and burning are present a) Peroxides

Typical emergency procedures 

b) Perchloric acid and chromic acid c) Halogens, such as bromine and iodine

LEAVE THE AREA IMMEDIATELY AND NOTIFY YOUR SUPERVISOR.

Water-reactive materials, such as lithium, react with water and form hydrogen gases, which are very explosive.

Examples of incompatible reactive materials include 

Cyanides (frequently used in plating) and acids;



Chloride bleach and ammonia (this combination forms high toxic chlorine gas).

Safety practices – chemical agents Safety practices that are of general nature associated with the use of oils and chemicals are given below. 

Identify the correct oil/chemical to be used. Improper and Incorrect use may result in injury or damage as certain chemicals when mixed together form highly combustible explosive mixtures.



Follow manufacturer’s instructions printed on container or leaflets accompanying the material.

Generally recommended personal safety equipment 

Gloves, aprons, respirator, and face shield or goggles are suggested.

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Shut down electrical equipment whenever possible. If there is any doubt in your mind regarding the degree of reactivity and toxicity of the substances involved,

the

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

Check for conditions for use as some chemicals may be forbidden from use unless certain conditions are met (E.g. proper ventilation, temperature etc.).



Use protective equipment such as gloves, goggles, masks, etc. Avoid contact at all costs with material such as sealants and lubrication compounds that are used in the aviation industry as most of them are identified carcinogens, which means exposure to such material (inhalation, skin contact) can significantly increase the chance of developing malignant cancers.



After use make sure by-products and any leftover material is disposed according to guidelines set by manufacturer or local authority.



Most of the oils and chemicals used in aviation are considered to be combustible especially in the presence of Oxygen. Therefore special consideration should be paid to working practices associated with such chemicals.



Always try to keep working area free from spills and clean up as soon as possible if spills do occur. Also try to keep the lids and caps closed of containers that hold such chemicals at all times except when in use.

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

If any combustible material is to be used then avoid taking large quantities to the work area, this can reduce the risk involved by trying to maintain a manageable situation even if something does go wrong.

In an emergency – oil and chemicals In case of a fire with oil or chemicals involved the type of chemical involved will be a factor of how intense or how fast the fire may spread and how much danger it may pose to the personnel and property. Most chemicals are likely to give off toxic fumes at elevated temperatures, therefore it is most advisable to vacate and isolate the area and let emergency services handle the situation. Only try to extinguish such fires if personally not at risk to do so and the fire is contained in a small area. If material that can react violently (explode) are present: vacate the area immediately and move to a location remote enough to be considered safe, or to pre-designated assembly areas to be used in case of such an emergency. Once assembled, a person in charge or designated person should perform a ‘roll-call’ to ensure all personnel have evacuated the area and that no one is missing. If possible cut off supply of all other types of fluids and de- energize the electrical system in the area of emergency. Physical hazards Physical hazards are those that are usually caused by the use of some type of equipment not directly controllable by the For Training Purpose Only Rev. 00 Mar 2014

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technician. Typically, this type of hazard is generated by the operation of equipment that can be detected by the human senses.

results in the potential for hazards to exist in areas where exposure is not usually a concern. X ray of aircraft structural parts is an example of such a situation.

However, many physical hazards that fall into this classification are not detectable by the human senses. These hazards include X rays, microwaves, beta or gamma rays, invisible laser beams, and high-frequency (ultrasonic) sound waves.

The aviation maintenance technician should remain conscious that potentially hazardous equipment is portable and remain vigilant for possible exposure in the work area.

Compressed liquids and gases, such as welding oxygen and acetylene, aviator's breathing oxygen, nitrogen, and hydraulic accumulators, present another physical hazard to the aviation maintenance technician. Although some of these substances by themselves present hazards as chemical agents, placing them under pressure may create another unique hazard.

According to labor rules it is required that areas where such exposure exists be clearly marked and that individuals exposed to these hazards be provided with the proper safety equipment. In many cases this is easily accomplished, but in the aerospace industry particular concern should be paid to portable equipment that generates these hazards. Such equipment SAFETY WITH FIRE Fire is one of humanity’s greatest discoveries. For all its many advantages, however, fire is capable of producing disaster in a matter of seconds. Fires continue to take their toll even though know how exists to prevent and retard fires. The ‘fire triangle’ ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 20

Fire results from the chemical reaction that occurs when oxygen combines rapidly with fuel to produce heat, (and light). Three essentials of this process form the ‘Fire Triangle’.

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There are a number of types of portable fire extinguishers. Each type of extinguisher may be rated for one or more classes of fire. In some cases, particular extinguishers are not only considered ineffective against certain classes of fire, they can be dangerous if used in those circumstances. The classes of fire are: Class A Ordinary Combustibles Class B Flammable and combustible liquids Class C Flammable gases Class D Combustible metals Class E electrically energized equipment Class F Cooking oils and fats

As can be seen, a fire requires three components to burn, and the removal of any one of these components will extinguish the fire. The requirements of the three components, forming the ‘Fire Triangle’, are:   

Fuel: a combustible material, which may be a solid, liquid or gas Oxygen: in sufficient volume to support the process of combustion Heat: of sufficient intensity to raise the temperature of the fuel to its ignition (or kindling) point.

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Portable fire extinguishers are distinguishable by their labels and their coloring. In 1999 the standard colors of some portable fire extinguishers were changed. It is therefore likely that you may encounter two of the same type of extinguisher with different colorings. Spontaneous ignition Aviation technicians need to be particularly aware of spontaneous ignition caused by the lubricants and solvents that are used in maintaining aircraft. Certain materials, such as rags soaked with oil or solvents, are capable of generating sufficient heat to cause combustion. These rags should be disposed of in airtight cans. 1. Ordinary combustibles "Ordinary combustible" fires are the most common type of fire, and are designated Class A under both systems. These occur when a solid, organic material such as wood, cloth, rubber, or some plastics [1] become heated to their flash point and ignite. At this point the material undergoes combustion and will continue burning as long as the four components of the fire tetrahedron (heat, fuel, oxygen, and the sustaining chemical reaction) are available.

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This class of fire is commonly used in controlled circumstances, such as a campfire, match or wood-burning stove. To use the campfire as an example, it has a fire tetrahedron - the heat is provided by another fire (such as a match or lighter), the fuel is the wood, the oxygen is naturally available in the open-air environment of a forest, and the chemical reaction links the three other facets. This fire is not dangerous, because the fire is contained to the wood alone and is usually isolated from other flammable materials, for example by bare ground and rocks. However, when a class-A fire burns in a less-restricted environment the fire can quickly grow out of control and become a wildfire. This is the case when firefighting and fire control techniques are required. This class of fire is fairly simple to fight and contain - by simply removing the heat, oxygen, or fuel, or by suppressing the underlying chemical reaction, the fire tetrahedron collapses and the fire dies out. The most common way to do this is by removing heat by spraying the burning material with water; oxygen can be removed by smothering the fire with foam from a fire extinguisher; forest fires are often fought by removing fuel by back burning; and an ammonium phosphate dry chemical powder fire extinguisher (but not sodium bicarbonate or potassium bicarbonate both of which are rated for B-class (fires) breaks the fire's underlying chemical reaction.

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As these fires are the most commonly encountered, most fire departments have equipment to handle them specifically. While this is acceptable for most ordinary conditions, most firefighters find themselves having to call for special equipment such as foam in the case of other fires. 2. Flammable liquid and gas A CO2 fire extinguisher rated for flammable liquids and gasses Flammable or combustible liquid or gaseous fuels. The US system designates all such fires "Class B". In the European/Australian system, flammable liquids are designated "Class B", while burning gases are separately designated "Class C". These fires follow the same basic fire tetrahedron (heat, fuel, oxygen, chemical reaction) as ordinary combustible fires, except that the fuel in question is a flammable liquid such as gasoline, or gas such as natural gas. A solid stream of water should never be used to extinguish this type because it can cause the fuel to scatter, spreading the flames. The most effective way to extinguish a liquid or gas fueled fire is by inhibiting the chemical chain reaction of the fire, which is done by dry chemical and Halon extinguishing agents, although smothering with CO2 or, for liquids, foam is also effective. Some newer clean agents designed to replace halon work by cooling the liquid below its flash point, but these have limited class B effectiveness.

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3. Electrical Electrical fires are fires involving potentially energized electrical equipment. The US system designates these "Class C"; the European/Australian system designates them "Class E". This sort of fire may be caused by, for example, short-circuiting machinery or overloaded electrical cables. These fires can be a severe hazard to firefighters using water or other conductive agents: Electricity may be conducted from the fire, through water, the firefighter's body, and then earth. Electrical shocks have caused many firefighter deaths. Electrical fire may be fought in the same way as an ordinary combustible fire, but water, foam, and other conductive agents are not to be used. While the fire is, or could possibly be electrically energized, it can be fought with any extinguishing agent rated for electrical fire. Carbon dioxide CO2, Halo and dry chemical powder extinguishers such as PKP and even baking soda are especially suited to extinguishing this sort of fire. Once electricity is shut off to the equipment involved, it will generally become an ordinary combustible fire.

Certain metals are flammable or combustible. Fires involving such are designated "Class D" in both systems. Examples of such metals include sodium, titanium, magnesium, potassium, steel, uranium, lithium, plutonium, and calcium. Magnesium and titanium fires are common, and 2006-7 saw the recall of laptop computer models containing lithium batteries susceptible to spontaneous ignition. When one of these combustible metals ignites, it can easily and rapidly spread to surrounding ordinary combustible materials. With the exception of the metals that burn in contact with air or water (for example, sodium), masses of combustible metals do not represent unusual fire risks because they have the ability to conduct heat away from hot spots so efficiently that the heat of combustion cannot be maintained - this means that it will require a lot of heat to ignite a mass of combustible metal. Generally, metal fire risks exist when sawdust, machine shavings and other metal 'fines' are present. Generally, these fires can be ignited by the same types of ignition sources that would start other common fires. Water and other common firefighting materials can excite metal fires and make them worse. The NFPA recommends that metal fires be fought with 'dry powder' extinguishing agents. Dry Powder agents work by smothering and heat absorption. The most common of these agents are sodium chloride granules and graphite powder. In recent years powdered copper has also come into use.

4. Metal ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 24

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Some extinguishers are labeled as containing dry chemical extinguishing agents. This may be confused with dry powder. The two are not the same. Using one of these extinguishers in error, in place of dry powder, can be ineffective or actually increase the intensity of a metal fire. Metal fires represent a unique hazard because people are often not aware of the characteristics of these fires and are not properly prepared to fight them. Therefore, even a small metal fire can spread and become a larger fire in the surrounding ordinary combustible materials.

5. Cooking oil ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 25

Laboratory simulation of a chip pan fire: a beaker containing wax is heated until it catches fire. A small amount of water is then poured into the beaker. The water sinks to the bottom and vaporizes instantly, ejecting a plume of burning liquid wax into the air. Fires that involve cooking oils or fats are designated "Class K" under the US system, and "Class F" under the European/Australasian systems. Though such fires are technically a subclass of the flammable liquid/gas class, the special characteristics of these types of fires are considered important enough to recognize separately. Saponification can be used to extinguish such fires. Appropriate fire extinguishers may also have hoods over them that help extinguish the fire.

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Fire Extinguisher

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Depending on the nature of a class of fire the best method for suppression may be one of the following:

responds best to carbon dioxide (CO2). CO2 displaces the oxygen in the atmosphere, making combustion impossible.

a. Cooling the fuel below its kindling point

The CO2 extinguisher must be equipped with a nonmetallic horn to be approved for use on electrical fires. Two reasons for this requirement must be considered:

b. Excluding the Oxygen supply c. Separating the fuel from the Oxygen



The discharge of CO2 through a metal horn can generate static electricity. The static discharge could reignite the fire.



The metal horn, if in contact with the electric current, would transmit that current to the extinguisher's operator.

These methods have led to the development of different types of extinguishers for different types of fires. Fire extinguishing agents Class ‘A’ Agents – Class ‘A’ fire extinguishers are water or water-type extinguishers as they are the most suited for suppressing class A fires. These extinguishers cool the fuel below combustion temperatures, which is the most effective method in containing class A fires. Class B and C extinguishers are effective but not equal to the wetting/cooling action of the Class A extinguisher. Class ‘B’ Agents – Class ‘B’ fires respond to carbon dioxide (CO2), Halogenated hydrocarbons (halons), and dry chemicals, all of which displace the oxygen in the air, thereby making combustion impossible. Foam is effective, especially when used in large quantities. Water is ineffective on Class B fires and in fact will cause the fire to spread.

Class ‘C’ Agents – Class ‘C’ fires are fires involving electrical wiring and equipment, ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 27

Halogenated hydrocarbons are very effective on Class C fires. The vapor reacts chemically with the flame to extinguish the fire. Dry chemicals are effective but have the disadvantage of contaminating the local area with powder. Also, if used on wet and energized electrical equipment, they may aggravate current leakage. Water or foam are not acceptable agents for use on electrical equipment, as they also may aggravate current leakage. Class ‘D’ Agents – Class ‘D’ fires respond to the application of dry powder, which prevents oxidation and the resulting flame. The application may be from an extinguisher, a scoop, or a shovel.

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the proper protective equipment installed. Under no conditions should a person use water on a metal fire. It will cause the fire to burn more violently and can cause explosions. The most common types of extinguishers are: Water - solid red

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Powder based agent that extinguishes by separating the four parts of the fire tetrahedron. It prevents the chemical reaction between heat, fuel and oxygen and halts the production of fire sustaining "free-radicals", thus extinguishing the fire. 

Ammonium phosphate, also known as "tri-class", "multipurpose" or "ABC" dry chemical, used on class A, B, and C fires. It receives its class A rating from the agent's ability to melt and flow at 177 °C (350 °F) to smother the fire. More corrosive than other dry chemical agents. Pale yellow in color.



Sodium bicarbonate, "regular" or "ordinary" used on class B and C fires, was the first of the dry chemical agents developed. It interrupts the fire's chemical reaction, and was very common in commercial kitchens before the advent of wet chemical agents. White or blue in color.



Potassium bicarbonate , used on class B and C fires. About two times as effective on class B fires as sodium bicarbonate, it is the preferred dry chemical agent of the oil and gas industry. The only dry chemical agent certified for use in ARFF by the NFPA. Violet in color.



Potassium bicarbonate & Urea Complex used on Class B and C fires. More effective than all other powders due to its ability to decrepitate (where the powder breaks up into smaller particles) in the flame zone creating a larger

Suitable for Class A fires. Not considered effective for Class Band Class C fires, and dangerous if used for electrically energized equipment or cooking oils or fats. Foam - red with blue band or label (previously solid blue) Suitable for Class A and Class B fires, with limited effectiveness for Class F fires. Not considered effective for Class C fires, and dangerous if used for electrically energized equipment. Powder - red with a white band or label These extinguishers are rated as either ABE or BE. ABE rated extinguishers are considered suitable for Class A, Class B, and Class C and Class E fires. They are not considered effective for Class F fires. BE rated extinguishers are considered suitable for Class B, Class C and Class E fires, and may be used with limited effectiveness on Class F fires. They are considered effective for Class A fires., or replacement, should be carried out annually.

Types of extinguishing agents Dry chemical ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 28

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surface area for free radical inhibition. 



Potassium Chloride, or Super-K dry chemical was developed in an effort to create a high efficiency, protein-foam compatible dry chemical. For B and C fires, white in color. Foam-Compatible, which is a sodium bicarbonate (BC) based dry chemical, was developed for use with protein foams for fighting class B fires. Most dry chemicals contain metal stearates to waterproof them, but these will tend to destroy the foam blanket created by protein (animal) based foams. Foam compatible type uses silicone as a waterproofing agent, which does not harm foam. Effectiveness is identical to regular dry chemical, and it is light green in color. This agent is generally no longer used since most modern dry chemicals are considered compatible with synthetic foams such as AFFF.

Foams Applied to fuel fires as either an aspirated (mixed & expanded with air in a branch pipe) or non-aspirated form to form a frothy blanket or seal over the fuel, preventing ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 29

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oxygen reaching it. Unlike powder, foam can be used to progressively extinguish fires without flashback. 

AFFF (aqueous film forming foam), used on A and B fires and for vapor suppression. The most common type in portable foam extinguishers. It contains fluoro tensides which can be accumulated in human body. The long-term effects of this on the human body and environment are unclear at this time.



AR-AFFF (Alcohol-resistant aqueous film forming foams), used on fuel fires containing alcohol. Forms a membrane between the fuel and the foam preventing the alcohol from breaking down the foam blanket.



FFFP (film forming fluoroprotein) contains naturally occurring proteins from animal by-products and synthetic film-forming agents to create a foam blanket that is more heat resistant than the strictly synthetic AFFF foams. FFFP works well on alcohol-based liquids and is used widely in motor sports.



CAFS (compressed air foam system) Any extinguisher that is charged with a foam solution and pressurized with compressed air. Generally used to extend a water supply in wild land operations. Used on class A fires and with very dry foam on class B for vapor suppression. For Training Purpose Only Rev. 00 Mar 2014

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in Europe. 



Arctic Fire is a liquid fire extinguishing agent that emulsifies and cools heated materials more quickly than water or ordinary foam. It is used extensively in the steel industry. Effective on classes A, B, and D. FireAde, a foaming agent that emulsifies burning liquids and renders them non-flammable. It is able to cool heated material and surfaces similar to CAFS. Used on A and B (said to be effective on some class D hazards, although not recommended due to the fact that fireade still contains amounts of water which will react with some metal fires).

Wet chemical and water additives 

Wet Chemical (potassium acetate, carbonate, or citrate) extinguishes the fire by forming a soapy foam blanket over the burning oil and by cooling the oil below its ignition temperature. Generally class A and F only, although newer models are outfitted with misting nozzles as those used on water mist units to give these extinguishers class B and C firefighting capability.



Wetting Agents Detergent based additives used to break the surface tension of water and improve penetration of Class A fires.



Antifreeze Chemicals added to water to lower its freezing point to about -40 degrees Fahrenheit. Has no appreciable effect on extinguishing performance.

Water Cools burning material. 

APW (Air pressurized water) cools burning material by absorbing heat from burning material. Effective on Class A fires, it has the advantage of being inexpensive, harmless, and relatively easy to clean up. In the United States, APW units contain 2.5 gallons (9 litres) of water in a tall, stainless steel cylinder. In Europe, they are typically mild steel lined with polyethylene, painted red, containing 6-9 litres (1.75-2.5 gallons) of water.

Clean agents and carbon dioxide Water Mist uses a fine misting nozzle to break up a stream of deionized water to the point of not conducting electricity back to the operator. Class A and C rated. It is used widely in hospitals for the reason that, unlike other clean-agent suppressants, it is harmless and noncontaminant. These extinguishers come in 1.75 and 2.5 gallon units, painted white in the United States and red ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 30 

Agent displaces oxygen (CO2 or inert gases), removes heat from the combustion zone (Halotron, FE-36) or inhibits chemical chain reaction (Halons). They are labeled clean agents because they do not leave any residue after discharge, which is ideal for sensitive electronics and documents. For Training Purpose Only Rev. 00 Mar 2014

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



Halo (including Halo 1211 and Halo 1301), a gaseous agent that inhibits the chemical reaction of the fire. Classes B: C for lower weight fire extinguishers (2.3 kg ; under 9 lbs) and A:B:C for heavier weights (4.1-7.7 kg ; 9-17 lbs). Banned from new production, except for military use, as its properties contribute to ozone depletion and long atmospheric lifetime, usually 400 years. Halon 1301 and 1211 are being replaced with new halocarbon agents which have no ozone depletion properties and low atmospheric lifetimes, but are less effective. Currently Halotron I, Halotron II, FE-36 Clean guard and FM-200 are meant to be replacements with significantly reduced ozone depletion potential.

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including sodium and potassium, and other metals including magnesium, titanium, aluminum, and zirconium. 

Copper based powder developed by the U.S. Navy in the 70s for hard-to-control lithium and lithium-alloy fires. Powder smothers and acts as a heat sink to dissipate heat, but also forms a copper-lithium alloy on the surface which is non-combustible and cuts off the oxygen supply. Will cling to a vertical surface-lithium only.



Graphite based extinguisher contains dry graphite that smothers burning metals. First type developed, designed for magnesium, works on other metals as well. Unlike sodium chloride powder extinguishers, the graphite powder fire extinguishers can be used on very hot burning metal fires such as lithium, but unlike copper powder extinguishers will not stick to and extinguish flowing or vertical lithium fires. Like copper extinguishers, the graphite powder acts as a heat sink as well as smothering the metal fire.



Sodium carbonate based extinguisher used where stainless steel piping and equipment could be damaged by sodium chloride based agents to control sodium, potassium, and sodium-potassium alloy fires. Limited use on other metals. Smothers and forms a crust.



Some water based suppressants may be used on certain class D fires, such as burning titanium and

CO2, a clean gaseous agent that displaces oxygen. Highest rating for 7.7 kg (20 pound) portable CO2 extinguishers is 10B:C. Not intended for Class A fires, as the high-pressure cloud of gas can scatter burning materials. CO2 is not suitable for use on fires containing their own oxygen source, metals or cooking media. Although it can be rather successful on a person on fire, its use should be avoided where possible as it can cause frostbite and is dangerous to use as it may displace the oxygen needed for breathing, causing suffocation.

Class D There are several Class D fire extinguisher agents available, some will handle multiple types of metals, others will not. Sodium Chloride contains sodium chloride salt and thermoplastic additive. Plastic melts to form an oxygenexcluding crust over the metal, and the salt dissipates heat. Useful on most alkali metals ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 31 

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magnesium. Examples include the Fire Blockade and FireAde brands of suppressant. Some metals, such as elemental Lithium, will react explosively with water, therefore water-based chemicals should never be used on such fires due to the possibility of a violent reaction. Most Class D extinguishers will have a special low velocity nozzle or discharge wand to gently apply the agent in large volumes to avoid disrupting any finely divided burning materials. Agents are also available in bulk and can be applied with a scoop or shovel.

INSTRUCTIONS INCASE OF FIRE Action that an individual take in case of an emergency can make the difference between life and death. Therefore, a proper training program can avert a disaster as personnel can take the right decisions and make the right actions to minimize damages and save lives.  ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 32

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of emergency services (e.g. fire): always sound the alarm first. This can either be by activating a fire alarm lever/pushbutton or calling the emergency desk number by phone. Give following details, Name, Location of emergency, Type of emergency and number of people if any involved. 

If danger exists of any physical harm to the people in the area take necessary action to vacate the area.

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Isolate electrical, compressed air gas supply if continued supply can aggravate the situation or endanger rescue personnel.

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Identify the type of fire and the extent before taking any action to extinguish the fire.

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Put on any protection clothing available in the area provided for such purposes.

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When searching for fire source or survivors, stay low if not wearing portable breathing equipment

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Select the appropriate type of fire extinguisher, check for contents and activate to check for proper operation.



If compartments or enclosed spaces need to be checked always use the back of the hand against the door to

ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 33

Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

sense the temperature of the door, this is to ensure that a raging fire is not present within the compartment. 

Fire in an enclosed area can be in a state of hibernation because of lack of oxygen within the compartment and could instantly intensify if oxygen is reintroduced; this is called ‘Flash back’. Therefore it is advisable to open any door slowly and just wide enough to get the extinguisher nozzle in to extinguish any fire.



When using an extinguisher aim at the base of the flames, at the near edge and bottom of the fire first, and then progress forward and upward. The discharge nozzle should be moved rapidly with a side-to-side sweeping motion. (Fig. B & D)

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In case of a fire on a person, smother flamed with a coat or blanket, do not fan the flames and never use a fire extinguisher on a person. Give medical attention immediately.

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If you had been successful in extinguishing the fire, maintain a vigil in case the fire re-ignites.

For Training Purpose Only Rev. 00 Mar 2014

PIA TRAINING CENTRE (PTC) Category – A/B1

ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 34

Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

For Training Purpose Only Rev. 00 Mar 2014

PIA TRAINING CENTRE (PTC)

Module 7 – MAINTENANCE PRACTICES

Category – A/B1

Sub Module 7.1 – Safety Precautions – Aircraft and Workshop



Everyone has left or is leaving the building.

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The fire is small and confined to the immediate area where it started.

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You can fight fire with your back to a safe escape route.

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Your extinguisher is rated for the type of fire you are fighting, and is in good working order.

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You have had training in use of the extinguisher and are confident that you can operate it effectively.

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If you have the slightest doubt about whether or not to fight the fire- DON'T! Instead, get out, and close the door behind you.

Do not fight a fire if:

Firefighter

Fight a fire only if: 

The Fire Department has been called.

ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 35



The fire is spreading beyond the immediate area where it started, or is already a large fire.

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The fire could block your escape route.

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You are unsure of the proper operation of the extinguisher.

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You are in doubt whether the extinguisher you are holding is appropriate for the type of fire. 

If any of these conditions are true, leave immediately, close off the area, and leave the fire to the Fire Department. For Training Purpose Only Rev. 00 Mar 2014

PIA TRAINING CENTRE (PTC)

Module 7 – MAINTENANCE PRACTICES

Category – A/B1

Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

Inspection and maintenance f. The National Fire Protection Association (NFPA) sets the standard for fire extinguishers in the regulation NFPA 10. This section will briefly explain the inspection and maintenance requirements for fire extinguishers. Inspection An inspection is a "quick check" that an extinguisher is available and will operate. It is intended to give reasonable assurance that the fire extinguisher is fully charged and operable. This is done by verifying that it is in its designated place, that it has not been actuated or tampered with, and that there is no obvious or physical damage or condition to prevent its operation. Fire extinguishers should be inspected when they are initially placed in service and thereafter at 30-day intervals. They may require more frequent inspections if circumstances dictate. Inspection procedures:

Examination for obvious physical damage, corrosion, leakage, or clogged nozzle.

g. Pressure gauge reading or indicator in the operable range or position. Note: Internal pressure is affected by temperature. h. Condition of tires, wheels, carriage, hose, and nozzle checked (for wheeled units). Personnel making inspections should keep a record of inspections, including those found to require corrective action. The record should include the date the inspection was performed, and the identity of the person conducting the inspection. Maintenance Maintenance intervals begin on the date of manufacture, which can usually be found on the extinguisher nameplate.

a. Located in designated place b. No obstruction to access or visibility c. Operating instructions on nameplate legible and facing outward d. Safety seals and tampers indicators not broken or missing. e. Fullness determined by weighing or "hefting". ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 36

For Training Purpose Only Rev. 00 Mar 2014

PIA TRAINING CENTRE (PTC) Category – A/B1

Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

It's easy to remember how to use a fire extinguisher- simply follow the steps- "P-A-S-S"

ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 37

Pull the Pin: Pull the pin at the top of the extinguisher that keeps For Training Purpose Only Rev. 00 Mar 2014

PIA TRAINING CENTRE (PTC) Category – A/B1

Module 7 – MAINTENANCE PRACTICES Sub Module 7.1 – Safety Precautions – Aircraft and Workshop

the handle from being pressed. Break the plastic seal as the pin is pulled. Aim: Aim the nozzle or outlet toward the fire. Some hose assemblies are clipped to the extinguisher body. Release the hose and point. Squeeze: Squeeze the handle to release the extinguishing agent. The handle can be released to stop the discharge at any time. Before approaching the fire, try a very short test burst to ensure proper operation. Sweep: Sweep from side to side at the base of the fire until it is out. After the fire is out, watch for remaining smoldering hot spots or possible reflash of flammable liquids. Make sure the fire is out.

ISO 9001:2008 Certified PTC/CM/B1.1 Basic/M7/01 7.1 - 38

For Training Purpose Only Rev. 00 Mar 2014