Basic Wildfire Awareness ACT Fire & Rescue Community Fire Units Learners Guide CFU Basic Wildfire Awareness
Learner’s Guide
Copyright 2011 by ACT Fire & Rescue. All rights reserved.
No part of this publication may be reproduced or transmitted in any form or by any means electronic or mechanical including photo‐copying and/or microfilm recording or by any information storage and retrieval system (except excerpts thereof for bona fide study purposes in accordance with the Copyright Act) without prior permission in writing from the Superintendent, Firefighter Development. Published by:
ACT Fire & Rescue
GPO Box 158
CANBERRA ACT 2601
AUSTRALIA
Version 1.1 November 2011
Telephone:
Facsimile:
Internet:
(02) 6207 8381
(02) 6207 9299
www.firebrigade.act.gov.au
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Contents Contents
Figures
INTRODUCTION iii viii IX Acknowledgment
ix Summary of Changes to Learners Guide
ix Overview
ix Who is this Manual for?
ix What is a Wildfire?
x Abbreviations
x Relationship to competency standards
xi Learning outcomes
xi Recognition of prior learning
xi Privacy Statement
xii CHAPTER 1 1 FIRE 1 1 Introduction
1 2 What is combustion?
1 3 What is fire?
1 4 The fire triangle
2 Oxygen
3 Heat
3 Fuel
3 5 The fire tetrahedron
4 6 Heat transfer
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7 Learner’s Guide
Radiation
5 Convection
6 Conduction
7 Methods of attacking the fire
8 Cutting off the oxygen supply
8 Reducing the temperature
9 Removing the fuel
9 Combination of methods
10 SUMMARY
11 Self-check questions
12 CHAPTER 2 14 FACTORS WHICH AFFECT WILDFIRE BEHAVIOUR 14 1 Introduction
14 2 Fuel
14 3 4 Types of fuel
15 Fuel size and quantity
15 Arrangement of fuel
16 Moisture content
16 Measuring fuel moisture content
17 Weather
18 Air temperature
18 Relative humidity
18 Wind speed and direction at the flaming zone
19 Level of atmospheric stability
21 Topography
22 Slope
22 Aspect
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Wind
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24 SUMMARY
25 Self-check questions
26 CHAPTER 3 28 WILDFIRE DEVELOPMENT 28 1 Introduction
28 2 Types of fire
28 Surface fire
28 Ground fire
29 Crown fire
29 3 Spotting
31 4 Parts of a wildfire
33 Head of a fire
34 Flanks or sides
34 Fingers
34 Rear or heel
34 Point of origin
34 SUMMARY
35 Self-check questions
36 CHAPTER 4 38 ON THE FIREGROUND 38 1 Introduction
38 2 Direct attack
39 3 Head attack and flank attack
41 4 Parallel attack
42 5 Indirect attack
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6 Mopping up and patrol
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46 SUMMARY
47 Self-check questions
48 CHAPTER 5 49 SAFETY ON THE FIREGROUND 49 1 Introduction
49 2 Job safety
49 3 Chainsaw Operations on the Fireground
50 Driving on or near a Fire ground
50 Specific wildfire hazards
51 Heat Stress
51 Smoke
53 Fatigue
54 Electrical Hazards
55 Structural Fire Hazards
55 Dangerous Trees
56 Changes in fire behaviour
56 4 Survival in life-threatening situations
57 5 L.A.C.E.S.
59 6 Communication Arrangements
61 7 Australasian Inter-agency Incident Management System (AIIMS)
61 Incident Action Plan (IAP)
63 Personal Protective Equipment
65 SUMMARY
71 Self-check questions
72 CHAPTER 6 74 Version 1.1 November 2011
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AIRCRAFT AT WILDFIRES Learner’s Guide
74 1 Introduction
74 2 Safety precautions
75 6 What to do if caught in a firebombing drop zone
75 SUMMARY
77 Self-check questions
78 ANSWERS TO SELF‐CHECK QUESTIONS 79 GLOSSARY 81 Version 1.1 November 2011
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Figures Figure 1: The fire triangle 2 Figure 2: The fire tetrahedron 5 Figure 3: Radiation 6 Figure 4: Convection 7 Figure 5: Conduction 7 Figure 6: Cutting off the oxygen supply 8 Figure 7: Reducing the temperature 9 Figure 8: Removing the fuel 10 Figure 9 Fire Intensity 19 Figure 10: The effects of wind 20 Figure 11: Effect of uphill slope 22 Figure 12: Lee slope turbulence 24 Figure 13: Types of fire 30 Figure 14: Parts of a wildfire 33 Figure 15: A head attack 41 Figure 16: A flank attack 42 Figure 17: Parallel attack 43 Figure 18: Indirect attack 44 Figure 19: Survival on the fireground 57 Figure 20: Protecting yourself from an approaching fire 58 Version 1.1 November 2011
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Introduction Acknowledgment ACT Fire & Rescue (ACTF&R) acknowledges the assistance of the Australasian Fire Authorities Council who provided much of the material used in this publication. Summary of Changes to Learners Guide Coding – 22023VIC Course in Basic Wildfire Awareness is accredited for the period 1st January 2010 to 31st December 2014. This replaces the previous course code 21587VIC, direct credit transfer arrangements exist between the old course and the new course (Australasian Fire and Emergency Service Authorities Council (AFAC) course accreditation documentation 271109). Overview The purpose of this manual is to provide a reference for ACTF&R Community Fire Unit members in Wildfire Awareness. This course provides national accreditation by delivering training and information on the risks associated on the incident ground and the precautions to take. Who is this Manual for? This manual is prepared for ACTF&R Community Fire Unit members. It covers the knowledge and techniques used to maintain safety on the fireground. The manual is designed as a training reference to be used under the guidance of a qualified instructor. The theory in the manual is to enhance skills that must be taught and supervised by instructors. This manual is not written as a self‐instructional text. It may not contain all of the information required by a CFU member, as some of this can only be gained through experience gained in wildfire operations. Version 1.1 November 2011
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What is a Wildfire? Throughout this manual, the term wildfire will be used to describe an unplanned fire which may include grass fires, forest fires and scrub fires. An understanding the principles of fire, wildfire behaviour, and wildfire fire fighting strategies is essential to maintain the safety of persons working on the fireground. This manual contains knowledge about: Combustion: 
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fire triangle and fire tetrahedron how fire spreads how materials burn methods of heat transfer Fire Behaviour: 
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features of a fire effects of weather effects of topography fuel stages of fire development spotting ground, surface and crown fires wildfire suppression techniques safety on the fireground safe work practices safe work practices around aircraft Fire Ground Structure  incident management and chain of command  communication arrangements This manual also contains:  self‐check exercises  a list of words and their meanings Abbreviations AFFF Aqueous Film Forming Foam, designed for use on Class B fires BFFF Bush Fire Fighting Foam, designed for use on Class A fires CO Carbon monoxide SOPs Standard Operating Procedures Version 1.1 November 2011
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Relationship to competency standards The following national competency forms the standard for Basic Wildfire Awareness
for ACTF&R CFU members. The manual and course also cover additional material
specifically for ACTF&R CFU members to meet agency specific requirements.
Assessment is competency based using assessment tools that have been developed
against this national competency:
Unit Code: 22023VIC Basic Wildfire Awareness
Learning outcomes This manual is based on the national competency 22023VIC Basic Wildfire Awareness. The learning outcomes and assessment criteria can be obtained from the ACTF&R Firefighter Training and Development Section. Recognition of prior learning If you wish to gain recognition for completing the training modules covered in this
learning manual, it is important that you consider the following questions:
What do I do if I already feel competent in this area?
If you feel that you have completed the appropriate training and experience, and think
that you have the required skills and competencies outlined in any of these training
modules, see your training officer. You may be granted credit.
To be granted credit, what do I need to do?
* Talk with your training officer to discuss the RPL process and what is required to
gauge your competence against the Standards. Your training officer may conduct
a pre challenge interview to assist in identifying any shortfalls.
* Produce certificates for relevant courses that you have successfully completed.
* Demonstrate the skills and knowledge that you wish to gain RPL for in a
Challenge Test
Should I have completed anything before attempting these training modules?
For the training in Basic Wildfire Awareness there are no pre-requisite units.
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Privacy Statement The ESA has undertaken a registration process with the Accreditation and Registration Council (ARC) of the Australian Capital Territory. In order to gain registration and maintain registration, the ESA is audited by the ARC for compliance with the Australian Quality Training Framework (AQTF) ‐ Standards for RTOs. In accordance with the Standards for RTOs, ACTF&R, under the ESA RTO, is bound by the Privacy Act 1988, in particular the following sections: Part II section 9 and 10. Part III Division 1 Section 13A. Division2 sections 14, 15 and 16. Division 3 section 16 A to F. Further information and the entire Act can be accessed at http://www.legislation.act.gov.au/a/current/p.asp ACT Fire & Rescue course participants can access their own personal training records. ACT Fire & Rescue maintains the privacy and confidentiality of all participants and as such, the personal records of individuals will not be disclosed to a third party without prior written consent. Version 1.1 November 2011
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CHAPTER 1 Fire 1 Introduction This chapter describes briefly the fire triangle and its three components: oxygen, heat and fuel, and the fourth component which forms the fire tetrahedron  the chemical chain reaction. The chapter also describes how heat is transferred and the methods that can be used to attack a fire. 2 What is combustion? Combustion is a process of oxidation. Oxidation is the combination of oxygen with a substance. At varying temperatures, most substances will combine with oxygen in the air (oxidise). When a substance is oxidising at such a rate that heat and light are being released, it is described as being ‘alight’ or ‘on fire’. 3 What is fire? Fire is a chemical reaction. The most common chemical reaction is the one between oxygen in the air and flammable vapours released by the fuel. In fire suppression it is important to know the components that must be present to bring about the chemical reaction of fire. The components necessary for a fire to burn or continue to burn are illustrated in the fire triangle as: Version 1.1 November 2011
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 oxygen  heat  fuel The three components of the fire triangle are shown in Figure 1. 4 The fire triangle A fire needs the components of fuel, heat and oxygen for its continued existence. Given fuel and oxygen, a certain amount of energy, as heat, needs to be applied before combustion will occur. When it does occur, it releases much more energy than has already been applied. The net result is excess energy which can:  contribute to the heating of air  be radiated from flames or burning fuel  be conducted as heat to other fuel particles Figure 1: The fire triangle Version 1.1 November 2011
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Oxygen This is found in the air we breathe. It is a colourless, odourless gas which makes up about one fifth of the volume of the atmosphere. Oxygen is necessary for fuel to burn. Heat plus oxygen causes a chemical reaction to occur in fuel, which produces more heat and gases and turns the remainder of the fuel into ash. In the process, oxygen is consumed and needs to be replaced by fresh oxygen moving from elsewhere for the fire to continue burning. This is why fanning a camp fire makes it burn more intensely. Heat Every fuel has a particular temperature at which it begins to burn (its ignition temperature). Fire will send a certain amount of heat energy into adjacent unburnt fuel. Initially, most of the heat energy is used to evaporate moisture and other volatile liquids. This is why flammability is less if fuel moisture content is high. Once the fuel has dried out, it will quickly reach ignition temperature if the heat is still arriving. When combustion occurs, the now burning fuel adds to the chain reaction that drives the wildfire. Heat can be transferred to adjacent fuels by:  radiation  convection  conduction Each of these methods of heat transfer will be examined later in this chapter. Fuel A fuel is anything that will burn under suitable conditions. Fuels can be grouped according to:  typesome fuels are more flammable than others due to volatile oils or compounds within them  sizelarge fuel particles take longer to burn than small particles Version 1.1 November 2011
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 quantitymore fuel may mean more heat being generated and faster combustion  arrangementif fuel pieces are densely packed, they may not dry out or oxygen may not be able to penetrate easily; if widely separated, the heat transfer may not be sufficient to bring pieces of fuel to ignition temperature.  moisture contentif there is too much moisture, then the fuel may not reach ignition temperature 5 The fire tetrahedron In a fire, a fourth component is also present during combustionthe chemical chain reaction. In the combustion process, a chemical chain reaction occurs between the fuel and oxygen and is promoted by heat. This reaction is essential to sustaining a fire. If this process is inhibited or interrupted, the combustion reaction is suppressed and the fire is extinguished. Thus the fire tetrahedron (a four‐sided triangular figure) shows that fire requires the interaction of four separate components:  oxygen  heat  fuel  chemical chain reaction The relationship between these four components is illustrated through the fire tetrahedron (see Figure 2.) Version 1.1 November 2011
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Chemical
chain reaction
He
at
Fuel
Heat
Oxygen
Fu
el
Chemical
chain reaction
Figure 2: The fire tetrahedron 6 Heat transfer As already mentioned, a fire's heat can be transferred to adjoining fuel in three ways. They are radiation, convection and conduction. Radiation Any hot object loses heat by giving out infra‐red radiation. This is a form of heat energy which travels in all directions from its source (the fire) to nearby objects. It is the direct heat you feel from a fire. Radiant heat does not need a medium to travel through. It can travel through a vacuum. For example, the sun’s energy travels through space, which is a vacuum, and warms the earth. When this radiation hits an object, it is absorbed and heats the object. Burning fuel and flames radiate large amounts of heat. The intensity of radiant heat will drop very quickly with increasing distance from its source. Radiant heat will directly act upon fuel immediately around the fire and bring it to a temperature where it may burn (see Figure 3.) The radiant heat comes from the flames and any smouldering fuel. In summary, the hotter a fire, the greater the amount of radiant heat, and the faster the fire will spread by radiation. Version 1.1 November 2011
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Figure 3: Radiation Convection Convection is the movement of heat through the heating of air. Air moves upwards when it is hotter than the surrounding air. As air rises and moves sideways with the wind, it will carry heat with it, and then gradually lose it to the surrounding air. As a fire gains in intensity, it will heat more air, which rises faster. Air must move in towards the fire at ground level to replace it. This is sometimes called indraft wind. This process forms the convection column of rising hot air above the fire. It also includes ash, embers and the smoke plume. Volatile components of fuel continue to burn as they rise. This is the main process occurring in flames (see Figure 4.) The stronger the convection, the further the volatile components of fuel travel as they burn, and the longer the flames. The flames from an intense fire burning in heavy ground fuels may reach and ignite the crowns of trees. Convection has several important implications for firefighters:  A fire may supply its own oxygen by continually drawing in a supply of fresh air  Very large fires may create strong indraft winds which may, in turn, alter the behaviour of the fire  The hot air rising from a fire often carries pieces of burning fuel which may then be carried forward in front of the fire and cause small fires to start well ahead of the main fire. This is called spotting Version 1.1 November 2011
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Figure 4: Convection Conduction Conduction refers to the transfer of heat through a solid object from a region of higher temperature to a region of lower temperature. Different substances conduct heat at different rates. For example, metals are more effective conductors of heat than wood. In wildfires, conduction refers to the movement of heat through the fuel itself (see Figure 5.) Any large piece of burning fuel will conduct heat, but this is generally a slow and minor source of heat transfer. Figure 5: Conduction Version 1.1 November 2011
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7 Methods of attacking the fire Understanding the fire triangle now gives you three ways to attack a wildfire. Each method is designed to break the fire triangle. You can:  cut off the oxygen supply and smother the fire  reduce the temperature and cool the fire  remove the fuel from the path of the fire and starve the fire Cutting off the oxygen supply This may be the quickest and most efficient form of attack with small fires (see Figure 6.) However, cutting off the oxygen supply of a large fire in the open is usually too difficult. Firefighters can use the following methods to cut off the oxygen supply to a small fire:  stamping out and beating out the flames along the edge of a control line  shovelling soil onto a fire. In most cases this will help to put the flames out, but embers may continue to burn slowly  laying foam on burning fuels Figure 6: Cutting off the oxygen supply Version 1.1 November 2011
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Reducing the temperature This is one of the most effective ways of stopping a wide range of fires. When water is added to a fire:  it absorbs a lot of the heat energy, and removes it as the water evaporates  it cools the fuel below its ignition temperature The main purpose of using water when fighting fires is to cool the fuel to the point where combustion stops. Water must be directed initially to the base of the flames, where combustion is occurring (see Figure 7.) Adding water to unburnt fuel increases its moisture content and makes it harder for it to reach its ignition temperature. Figure 7: Reducing the temperature Removing the fuel Removing the fuel may be an effective way of stopping a fire (see Figure 8.) Additionally, it may be the best way to prevent large fires from occurring. Dry firefighting is the term used to describe firefighting techniques that do not involve the use of water. The following techniques are examples of dry firefighting: Version 1.1 November 2011
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 the use of hand tools to break up fuel and remove it from the heat of a low to moderate intensity fire  the use of hand tools to remove fuels and create a narrow control line as an edge for back burning to control a moderate intensity fire  the use of machinery such as bulldozers to make a wide break or to clear a large area to stop a large fire, or to provide an edge for a large backburn  backburning, that is removing fuels from the path of a wildfire Figure 8: Removing the fuel Combination of methods Although the methods of extinguishing a fire have been dealt with separately in this section, it should be understood that, in many instances, it is a combination of methods that brings about extinguishment. For example, the main effect of water is to cool the fire. However, the production of steam has a minor secondary effect. It helps smother the fire by keeping out the oxygen. Also, where water is used to extinguish a flame front, a control line bare of fuels may also be constructed to minimise the possibility of the fire re‐igniting and spreading. Version 1.1 November 2011
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SUMMARY  Fire is a chemical reaction.  Oxygen is a colourless, odourless gas which makes up about one fifth of the volume of the
atmosphere. It is an essential component of combustion.  Combustion is a process of oxidation. At varying temperatures most substances will oxidise
with oxygen in the air. When a substance is oxidising at such a rate that heat and light are
being released, it is described as being ‘alight’ or ‘on fire’.  The fire triangle illustrates the three components necessary for a fire to burn and continue to
burnoxygen, heat and fuel.  The fire tetrahedron (a four‐sided triangular figure) shows that fire requires a chemical chain
reaction to take place. If it is interrupted, the fire will be extinguished.  Fuel is anything that will burn under suitable conditions. Every fuel has a particular
temperature at which it begins to burn. This is its ignition temperature.  Heat is transferred by radiation, convection and conduction.  Radiation is a form of heat energy which travels in all directions from its source.  Convection occurs when heated air is displaced, usually upwards. As it rises, it carries heat
with it and gradually loses it to the surrounding air.  Conduction refers to the transfer of heat through solid objects from a region of higher
temperature to a region of lower temperature.  Three methods of attacking the fire are:  cut off the oxygen supply and smother the fire  reduce the temperature and cool the fire  remove the fuel from the path of the fire and starve the fire.  Fire can also be attacked by using a combination of these methods.  Dry firefighting is the term used to describe firefighting techniques that do not involve the use of water. Version 1.1 November 2011
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Indicate whether the following statements are true or false:
T F 1. Fire is a chemical reaction. Self‐check questions 2. A fire only needs fuel and heat for it to continue to burn.
3. Combustion is a process of oxidation.
4. The fire tetrahedron includes the three components oxygen, heat and fuel, and
a fourth component  the chemical chain reaction. 5. Fuel is anything that can burn under the right conditions.
6. Heat transfer occurs only through radiation and convection.
7. Radiant heat needs a medium to travel through.
8. Convection is the transference of heat through the heating of air.
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9. Conduction refers to the transfer of heat through a solid object from a region of
higher temperature to a region of lower temperature. 10. Removing the fuel is in fact smothering the fire.
11. Cutting off oxygen to a fire in fact cools the fire.
12. Reducing the heat from a fire in fact cools a fire.
13. Cooling the fuel is the only effective way of stopping a wildfire.
14. Water cools the fuel to the point where combustion stops.
15. Dry firefighting techniques involve the use of water.
Check the answers section at the back of this manual to see how you
went. Version 1.1 November 2011
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CHAPTER 2 Factors which affect wildfire behaviour 1 Introduction Fires are dynamic by nature. Their movement and behaviour can be described in terms of flame height, rate of spread (how quickly the fire is moving through the fuels), spotting behaviour and overall intensity. Fire behaviour depends on three main factors, namely fuel, weather and topography. 2 Fuel Fuel may be rated as one of the most important factors influencing the way fire behaves and travels. Fuel varies in its:  type  size and quantity  arrangement  moisture content Version 1.1 November 2011
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Types of fuel In Australia, common fuel components include:  grass (usually after it is partly or fully cured, that is, dried out after it dies)  litter lying on the ground  small herbs and shrubs  decomposing humus and duff (fine ground litter)  shrubs (heath lands or as an understorey layer)  trees (eucalypts, wattles, she‐oaks, pine trees)  material remaining after logging (including sawdust) Most of these fuels will ignite and burn readily given the right conditions. They will burn with different degrees of intensity. Grass fires, for example, may spread more rapidly than a fire in a tall, dense forest which generally burns slower but more intensely. Eucalypt fuels, in particular bark, are well known for causing spotting. Fuel size and quantity Fuel is normally classified as fine or heavy (coarse). Fine fuels (less than 6mm in diameter) such as leaves, twigs and grasses burn readily and cause spotting as the burning embers are carried through the air, starting new fires ahead of the main fire. Coarse or heavy fuels (greater than 6mm in diameter) such as sticks, branches and logs tend to ignite less readily and burn more slowly. It is mainly fine fuels that drive the forward spread of a fire, while the heavy fuels are consumed in the smouldering zone behind the main fire front. The fine fuel is ignited first, then this heats the heavy fuel, enabling it to burn. The proportion of fine fuel and heavy fuel affects the rate of spread and intensity of the fire. The volume of fuel affects fire behaviour. Generally, the more fine fuel there is, the greater the rate of spread, and the greater the intensity of the fire. Version 1.1 November 2011
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Arrangement of fuel Depending on the size of the individual fuel particles, the way pieces of fuel are arranged in relation to one another affects how they burn. Well‐separated pieces of fuel are harder to ignite than more closely grouped collections of the same material. This is because radiant heat diminishes rapidly the further it travels. Fuels that are tightly packed together or compacted, such as peat, smoulder slowly because of the lack of oxygen and generally higher moisture content. Fine, loosely stacked materials burn quickly and fiercely. A continuous ladder of fine fuel from the ground surface to the crown of the vegetation encourages crown fire development. Moisture content Fire behaviour is affected by how damp fuels are, that is their moisture content. The fuel moisture content will vary depending on factors such as weather conditions, vegetation type, the moisture content of the soil and whether the fuel pieces are dead or living vegetation. Fuel that is dry and fine will burn better than heavy fuels that are wet. Some grasses for instance, will not burn readily until fully dried out (cured). All dead fuels take up or give off moisture according to:  the daily temperature and humidity cycles. Dead fine fuels change their moisture content rapidly in response to these cycles, while heavy fuels vary slowly and rarely reach extremes of wetness or dryness  the time since last rainfall and the amount of rain received. Over a number of days, the effects of recent rainfall will disappear. This happens more rapidly in fine fuels than in heavy fuels  the dryness of the soil. Dry soil will dry out fuels in contact with it, and wet soils will moisten such fuels As there is normally more moisture in heavy fuel, it takes more heat to dry the fuel and cause ignition. For this reason, most heavy fuels burn much slower than finer fuels. Version 1.1 November 2011
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The dryness (or moisture content) of fuels affects:  ease of ignition  probability of spotting  rate of combustion  rate of fire spread  the amount of heat radiated from the flames The drier the fuel, the greater are these factors for the type of fuel that is burning. Measuring fuel moisture content Several techniques can be used to measure the moisture content of fuels. Fuel moisture content is sometimes estimated by taking into account weather conditions, temperature, relative humidity and the current seasonal dryness. Visual assessments of grass and crop lands can also be used. The most common technique used, however, involves drying fuel samples in an oven and determining the moisture content by measuring the weight difference before drying and after drying. Version 1.1 November 2011
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3 Weather Weather is the second major factor that impacts on the spread of fire. The four key elements of weather are:  air temperature  relative humidity  wind (speed and direction) at the flaming zone of the fire  atmospheric stability Air temperature The sun warms solid objects, such as fuels, and the surface of the land. This has the effect of raising the temperature of the fuels and the air. A change in temperature, and the resulting change in relative humidity, will change the fuel moisture content and thus ease of ignition. Thus higher temperatures normally mean fuel pieces that are warmer, drier and more easily ignited. Relative humidity All air contains a certain amount of water in an invisible gaseous form called water vapour. Relative humidity is a measure of the water vapour content of the air as a percentage of its water vapour holding capacity at the same temperature. In the absence of rain, the amount of moisture in dead finer fuels, for example leaves, litter and grass, varies according to the level of humidity in the air. On humid days, fine dead fuels absorb moisture from the air and burn more slowly or may not burn at all. On dry days with low humidity levels, the air will draw moisture out of these fuels and they will ignite more easily, and burn faster and more fiercely. The temperature and relative humidity vary throughout the day (see Figure 9.) Version 1.1 November 2011
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Figure 9 Fire Intensity Fire intensity increases as the temperature rises and relative humidity falls during the day. It is reduced as humidity increases and temperature drops at night. Wind speed and direction at the flaming zone Wind speed is an important factor in determining the intensity of a fire, the speed at which it travels and how it is controlled. Wind supplies oxygen for the burning process, removes ash and smoke from the area and has the effect of increasing the rate of burning. The stronger the wind, the more oxygen is supplied to the fire and the more smoke is removed. Wind slants the flames over the fuel ahead of the fire and causes the flames to be closer to the ground. This increases the heating effect of flame and radiation on the unburnt fuels ahead. The effect of this is to spread the fire more quickly from one piece of fuel to another. Wind also bends the convection column through taller vegetation ahead of the fire, causing it to dry out rapidly. This may allow the subsequent ignition of this vegetation. The wind may also lift burning materials, such as bark and other embers, and carry them ahead of the main fire to start new fires. These are called spot fires (see Figure 10.) Version 1.1 November 2011
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Figure 10: The effects of wind Wind direction refers to the direction the wind is coming from. For example, a north wind describes a wind originating from the north of where you are standing and travelling in a southerly direction. Sudden changes in wind direction can cause shifts in the fire front. These shifts can be particularly dangerous if they occur unexpectedly. Firefighters require information regarding any potential changes in wind direction to help them attack a fire and to ensure crew safety in the event of the fire changing direction. Each locality has its characteristic winds. Some of these bring the hot, dry conditions that cause problems for firefighters. Other local winds may be relied upon to bring cooler conditions. Generally, winds that blow from the centre of the continent are hotter and drier than those which blow from the sea. A knowledge of local wind patterns is helpful to firefighters. WARNING A dangerous aspect of wind change is that it can alter the direction of the fire without warning. This can cause long and relatively quiet fire flanks to suddenly become active fire fronts. Version 1.1 November 2011
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Level of atmospheric stability Atmospheric stability refers to the vertical movement of air masses which occurs when hot air rises and is replaced by cooler air. Atmospheric stability is important because vertical air motion can affect local wind patterns. Atmospheric stability also determines, to a large extent, cloud development and in particular the possibility of thunderstorm development. In stable atmospheric conditions:  stratus type clouds (the clouds are in layers) are present  smoke columns drift apart after limited rise  the vertical movement of air is limited  there are fog layers  the winds are generally light and predictable Fire behaviour will be predictable in these circumstances. In unstable atmospheric conditions, fire behaviour is erratic. Convection columns will develop rapidly and intense spotting may occur with little warning. In turn, the airflow into the fire at low levels is increased, and this has a marked effect on fire intensity. In unstable atmospheric conditions:  cumulus (cotton wool) type clouds show noticeable vertical growth  smoke columns can rise to great heights  winds are gusty and unpredictable  lightning strikes may occur from thunderstorms  dust whirls (willy willies) may occur Fire behaviour can be unpredictable under these conditions. Version 1.1 November 2011
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4 Topography Topography describes the lay of the land, that is the shape of the terrain. The topography will affect the direction and speed at which a fire will travel. The effects can be quite complex as the topography will at the same time modify the local wind speed and direction. Slope If a fire is travelling upslope, there will be a shorter distance for radiant heat to travel from the flames to unburnt fuel. Upslope fuels will be preheated to their ignition temperature more quickly. Slope can then affect the speed of a fire (see Figure 11). A rule of thumb that may be used is, for every 10 degrees of upslope, double the rate of spread. For downslope, while fire spread may be slower, consider it at the same rate of spread as on flat ground. Figure 11: Effect of uphill slope Version 1.1 November 2011
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Aspect Aspect is the direction that a feature or slope faces. This will influence the amount of solar radiation that is received. Therefore, northerly and westerly aspects will be warmer and drier than southerly and easterly aspects. This will also influence the nature of the vegetation growing on different aspects. For example, northern and western aspects will generally have drier and more flammable vegetation than southern and eastern aspects where vegetation will tend to be lush and less flammable. Therefore, fires on northern and western aspects will generally burn more fiercely than fires on southern and eastern aspects. Version 1.1 November 2011
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Wind The way that wind interacts with terrain can be quite complex. Exposed faces of hills and ridges will have increased windspeeds, while their leeside may be almost calm. Under some circumstances, the leeside can have dangerous turbulent winds blowing in the reverse direction (see Figure 12.) Valleys may have similar conditions. Figure 12: Lee slope turbulence Version 1.1 November 2011
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SUMMARY  The three factors that affect fire behaviour are:  fuel  weather  topography.  Fuel varies according to its:  type  size and quantity  arrangement  moisture content.  Fine fuels burn readily given the right conditions. Coarse or heavy fuels tend to ignite less
readily and burn more slowly. Most fuels are made up of both fine and heavy fuels.  The arrangement of fuels affects how they burn.  Fire behaviour is affected by how damp fuels are, that is, their moisture content.  The four key elements of weather that impact on fire behaviour are:  air temperature  relative humidity  wind speed and direction at the flaming zone  atmospheric stability.  Topography is the lay of the land, that is, the shape of the terrain. It affects the way in which a
fire will travel.  Slope can affect the speed of a fire. A rule of thumb that may be used is, for every 10 degrees
of upslope, double the rate of spread.  Aspect influences how dry fuels are and how rapidly fires burn. Version 1.1 November 2011
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Indicate whether the following statements are true or false:
T F 1. Fire behaviour depends on fuel, weather and topography.
Self‐check questions 2. Fuel is a key factor in determining fire behaviour and travel.
3. Well‐separated fuels are harder to ignite than closely grouped collections of fuel. 4. Fine, loosely stacked fuels burn slowly. 5. Fire behaviour is affected by the moisture content in fuel.
6. Dead fuels are unable to take up or give off moisture.
7. The dryness of fuel affects ease of ignition, probability of spotting, rate of
combustion and fire spread, and the amount of heat radiated from the flames. 8. The key elements of weather are air temperature, relative humidity, wind
(speed and direction) and atmospheric stability. Version 1.1 November 2011
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9. Humidity refers to the water vapour contained in the air.
10. Wind speed has no effect on the intensity of a fire and the speed at which it travels. 11. Atmospheric stability affects vertical air motion and this affects local wind
patterns. 12. Topography refers to the lay of the land.
13. Fires travel faster downslope than upslope.
14. Southerly and easterly aspects are warmer and drier than northerly and
westerly aspects. Check the answers section at the back of this manual to see how you
went. Version 1.1 November 2011
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CHAPTER 3 Wildfire development 1 Introduction Wildfires can be generally described in terms of the fuel in which they are burning. This chapter examines briefly the characteristics of the different types of fire, and defines important parts of a wildfire’s perimeter (see Figure 13.) 2 Types of fire Surface fire This type of fire travels just above ground surface in vegetation such as grass, low shrubs and forest litter. Characteristics:  by far the most common type of fire  burns in fuels lying on the ground  consumes only litter and low vegetation, such as grass  does not extend into the crowns of trees Version 1.1 November 2011
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Ground fire This type of fire burns the organic material in the soil layer, as happens in a peat fire, and often also the surface litter and small vegetation. Characteristics:  occur only in a few parts of Australia  smoulder with no flame and little smoke. This can be a problem because they can burn unnoticed and may later ignite surface fires Crown fire This is a fire which burns in the crowns of trees ahead of, and above, an intense surface fire in the undergrowth. Radiant heat and direct flame contact resulting from the surface fire ignites the tree tops. Strong winds carry the fire along the upper storey vegetation. Version 1.1 November 2011
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Characteristics:  It is a fast‐travelling fire that is most destructive and usually consuming all in its path  Crown fires are followed shortly afterwards by an intense surface fire  Often crown fires are accompanied by short or long distance spotting. For example, spotting distances of up to 25 kilometres have been recorded  Falling material from a crown fire can start further surface fires below  Crown fires are exposed to higher wind speeds in the open air and because of this can move faster than surface fires Ground fire Surface fire Crown fire Figure 13: Types of fire Version 1.1 November 2011
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3 Spotting A spot fire is a new fire which has been ignited ahead of a main fire by embers or a burning object often called a fire brand. This occurs when hot, convected air from a fire lifts the embers and drops them in front of the main fire. Factors that impact on spot fires are:  atmospheric instability, which determines how vigorous the convection column is and how easily it can carry embers aloft  fuel moisture content  breaks in a forest canopy which cause downdrafts  the nature of the fuels being burnteucalypt stringy bark is most prone to causing mass spotting. Stringy bark eucalypts are commonly associated with mass, short‐ distance spotting (up to one or two kilometres), whereas candle barked eucalypts may be associated with very long‐distance spotting Some problems arising from spot fires are:  the effective rate of spread of a main fire front may accelerate rapidly if spot fires start ahead of it  in a wind of varying direction, the spread of spot fires will be unpredictable  turbulence on lee slopes and elsewhere may drive spot fires back towards the main front and may cut off firefighters Version 1.1 November 2011
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WARNING If fire brands start to fall in the area around you and many spot fires begin to occur in the area, the situation is critical. You must evacuate from the area immediately. Do not attempt to suppress multiple spot fires unless you have sufficient resources and a large, safe refuge is available. Did you know? Forest wildfires usually start between 1300 hours and 1500 hours, the driest time of the day. Version 1.1 November 2011
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4 Parts of a wildfire The shape of a wildfire may be defined by its perimeter  the edge of the burnt area. Within this there may be burning areas, smouldering areas and blackened areas, as well as pockets of unburnt fuel. There will also be a point of origin that may or may not be identifiable without detailed investigation. Components of the perimeter as illustrated in Figure 14 include:  the head  the flanks or sides  the fingers  rear or heel (or sometimes referred to as the back)  spot fires ahead of the main fire Figure 14: Parts of a wildfire Version 1.1 November 2011
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Head of a fire The head of a fire is where the fire is making its greatest progress (usually downwind or upslope) measured by its forward rate of spread. The head is also called the fire front. Flames are tallest and intensity of the fire is greatest at this point. The head of the fire is influenced by wind direction, fuel factors and topography and will change accordingly. Flanks or sides Both sides of the fire between the head and the rear are called the flanks. They are roughly parallel to the main direction of spread. The intensity of the fire at the flanks is less than at the head. Often they are described by their geographic location (for example, the eastern flank of a fire) or by their orientation as viewed from the rear of the fire (for example, the left or right flank of a fire). Fingers These are long and narrow slivers of the advancing fire which extend beyond the head or flanks, and are caused by varying wind direction or variations in fuel. Rear or heel This is the section of the perimeter opposite to, and usually upwind, or downslope from, the head of a fire. It is the least intense part of the fire’s perimeter, with the lowest flames and slowest rate of spread. It may be described as the back of the fire. Point of origin This is the area where the fire started. The likely point of origin should, if possible, be left undisturbed for later fire cause investigation. Version 1.1 November 2011
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SUMMARY  Fires are described in terms of the fuels in which they are burning.  A surface fire burns in surface vegetation such as grass, scrub and forest litter.  A ground fire burns the organic material in the soil layer, as in a peat fire, and often also the
surface litter and small vegetation.  A crown fire burns in the crowns of trees ahead of and above an intense fire in the
undergrowth.  A spot fire is a new fire which has been ignited ahead of a main fire by embers or a burning
object often called a fire brand. These fires sometimes occur many kilometres ahead of the main fire.  The perimeter is the entire outer boundary of a wildfire.  A wildfire is defined by its perimeter:  the head  the flanks or sides  the fingers  rear or heel (or sometimes referred to as the back)  point of origin.  The head is the part of a fire where the rate of spread, flame height and intensity are greatest,
usually when burning downwind or upslope. The flanks or sides are the sides of a wildfire between the head and the rear.
 The fingers are slivers of the advancing wildfire which extend beyond the head or flanks.  The rear or heel is the section of the perimeter opposite to, and usually upwind or downslope
from, the head of the fire.  The point of origin is where the fire started. Version 1.1 November 2011
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Indicate whether the following statements are true or false:
T F 1. A surface fire burns the organic material in the soil layer. Self‐check questions 2. A ground fire burns in surface vegetation.
3. A ground fire smoulders with no flame and little smoke.
4. A crown fire burns in the crowns of trees ahead of a fire in the undergrowth.
5. Spotting occurs when hot, convective air from a fire lifts the embers and carries
them in front of the main fire. 6. The shape of a wildfire may be defined by its perimeter.
7. The head of a fire is influenced only by wind direction and fuel.
8. The intensity of a fire is greatest at its flanks.
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9. The fingers usually extend beyond the heads or flanks.
10. The point of origin is where the fire started.
Check the answers section at the back of this manual to see how you
went. Version 1.1 November 2011
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Chapter 4 On the Fireground 1 Introduction In Chapters 2 and 3 you were introduced to the basic principles of fire behaviour and how fire spread can alter dramatically depending on changes in fuel, weather and topography. In this chapter, the techniques involved in suppressing a wildfire are briefly covered. These fall broadly into two categories:  offensive strategies where the fire can safely and effectively be attacked or extinguished  defensive strategies where the fire is too remote or too intense to be safely or effectively attacked or extinguished. Offensive strategies usually include:  Direct Attack  Parallel Attack  Indirect Attack This chapter also covers mopping‐up operations and the roles of Emergency Services personnel on the fireground. Version 1.1 November 2011
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2 Direct attack A direct attack is used mainly on low intensity wildfires that can be easily and safely reached by firefighters. Firefighters work directly on the edge of the fire (see Figure 16.) This edge then becomes the established control line. In bushland settings, firefighters, using handtools or mechanical equipment such as bulldozers can clear a strip of exposed earth (called a mineral earth control line) along the fire’s perimeter. Be careful not to drag burning material across the control line. You may need to push fuel into the fire in some circumstances. Firefighters may also use water, foam and fire retardants to extinguish a fire. In grassland situations, water is commonly used to extinguish the burning edge of the fire. A mineral earth control line may not be required. To make a direct attack you can use:  water contained in knapsacks or tankers, or in hoselines from a static water source  bull dozers and other earth moving equipment  handtools such as axes, rakehoes (McLeod tools) and chainsaws The advantages of a direct attack are:  less area is burnt  the fuel is removed from the immediate path of the fire, allowing the earliest possible control  parts of the fire edge that may have gone out may be quickly incorporated into the fire line The disadvantages of a direct attack are:  firefighters working at the fire’s edge can be exposed to heat and smoke  an irregular control line has to be constructed in a short time (if the fire’s perimeter is irregular) Version 1.1 November 2011
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 fences and natural barriers may present obstacles  patrol of the constructed control line can be difficult Warning Community Fire Units never undertake direct attack of fires, but they do protect properties in the direct path of a fire. Version 1.1 November 2011
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3 Head attack and flank attack A head attack involves directly knocking down the head of the fire (see Figure 15.) This type of attack is used only for low intensity wildfires where you can get close enough to attack the burning edge and where you can be sure that the fire will not flare up unexpectedly. Figure 15: A head attack By contrast, a flank attack involves approaching the fire from the flanks and working directly on them if possible (see Figure 16.) A version of flank attack is to work from the rear progressively towards the head of the fire in an attempt to “pinch” it out. This technique is used when it is impractical or unsafe to approach the head of a fire front on. Version 1.1 November 2011
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Figure 16: A flank attack Warning Community Fire Units do not undertake a flank attack on a fire, but protect properties on the flanks or in the way of the head of fires. 4 Parallel attack This technique is used for low to medium intensity fires. It involves the construction of a control line parallel to the fire, or just a short distance away from the fire’s edge (see Figure 17.) The distance back from the fire will depend on:  the intensity of the fire  the type of fuel  weather conditions  topography. Version 1.1 November 2011
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In general, control lines are constructed as close as possible to the flanks of the fire and irregularities in the fire’s perimeter can be by‐passed using this technique. You can use a range of equipment to construct control lines, for example handtools, ploughs, bulldozers and chain saws. The fuel between the main fire and the control line can be burnt out by other firefighters as the work on the control line proceeds. If this is not possible, you must patrol the control line to ensure that it is not crossed when the main fire reaches it. Figure 17: Parallel attack Version 1.1 November 2011
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5 Indirect attack This technique is used for intense and inaccessible wildfires. The indirect method requires the use of either a natural fire barrier or the construction of a control line some distance from the fire’s existing perimeter. The fuel between the control line and the main fire is backburned. By backburning some distance from the wildfire’s existing perimeter, the fire is robbed of fuel. This technique is generally used when firefighting at close range is not possible, either because of the terrain, or because the fire is too intense (see Figure 18.) Figure 18: Indirect attack The advantages of an indirect attack are:  can be used to control a more intense wildfire  it reduces the exposure of firefighters to the effects of wildfire  it allows choice of better locations for control lines Version 1.1 November 2011
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 it allows more time for control line construction The disadvantages of an indirect attack are:  the size of the fire is increased  the increased size gives a greater area to be controlled and patrolled and there is a greater chance of the fire breaking through the control lines  the fuel between the fire and the control line may have to be backburned. The two fires joining may result in intense fire activity at the junction zone (where the fires meet) and an increased chance of spotting Note Indirect attack of a fire includes cleaning up your property prior to the summer Version 1.1 November 2011
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6 Mopping up and patrol Mopping‐up (or blacking‐out) operations involve making sure that a contained or checked fire does not restart. When the perimeter of a wildfire is extinguished, a strip inside the perimeter must be blacked out to extinguish all smouldering material. The width of this strip will vary. Your Incident Controller or crew leader will tell you how far inside the control line this work should be taken. The depth will depend on:  the size of the wildfire  it may be possible to mop‐up the entire area of small fires  nature of the fuels  lots of heavy, smouldering fuels inside the mopped‐up perimeter increase the risk of re‐ignition. The mopped‐up margin may need to be deeper  terrain or topography  control lines on slopes with burnt ground above have a risk of smouldering material tumbling down across the line. Mopping up must be extended further upslope to reduce this risk  weather conditions  the likelihood of severe weather in the near future may make a deeper mopped‐up zone desirable A mopping‐up operation involves locating and extinguishing any smouldering fuel above or below ground. This is done manually with hand tools, or by wetting the fuel, or both. You should:  extinguish any smouldering and hot materials  place any smouldering fuel found outside the control line into the burnt out area  break up fuel concentrations to release the heat  turn smouldering logs into a position where they will not roll into an unburnt area  dig out and extinguish burning roots and stump holes  extinguish any fresh outbreaks The felling of burning trees, which could fall into unburnt areas or provide wind blown embers, should only be conducted by suitably trained personnel. Version 1.1 November 2011
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SUMMARY  Direct attack is when firefighters work directly on the edge of the wildfire and this edge then becomes the established control line.  Parallel attack involves the construction of a control line parallel to the fire, or just a short
distance away from the fire’s edge.  An indirect attack requires the use of a control line some distance from the wildfire. The fuel
between the control line and the main fire is usually backburned or allowed to be burnt by the
fire itself.  A head attack involves directly knocking down the head of the wildfire, whereas, a flank attack
involves approaching the wildfire from the flanks and then pinching out the head.  Mopping‐up operations involve making sure that a contained or checked fire does not restart.  When firefighting, stay in contact with other people either by sight or radio. Version 1.1 November 2011
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Indicate whether the following statements are true or false:
T F 1. A direct attack is used mainly on low intensity wildfires.
Self‐check questions 2. A parallel attack is used for low to medium intensity wildfires.
3. An indirect attack is used for intense and inaccessible wildfires.
4. A head attack involves directly knocking down the head of a fire.
5. The methods used for fighting a wildfire depend on factors such as the rate of
spread, wildfire intensity, spotting, fuel and available resources. 6. Mopping‐up operations involve only locating and extinguishing smouldering
fuel above ground. 7. When fire spread has been checked by the construction of a control line, the
perimeter of a fire must be monitored by patrolling firefighters. Check the answers section at the back of this manual to see how you
went. Version 1.1 November 2011
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Chapter 5 Safety on the fireground 1 Introduction Working on the fireground requires that you are conscious of safe work practices and potential hazards at all times. This chapter discusses these issues under the three headings:  Job Safety  Specific Wildfire Hazards  Survival in Life‐Threatening Situations 2 Job safety Any work undertaken on the fireground can be dangerous, particularly when you are:  using equipment with cutting edges, for example axes, rakehoes and chain saws  operating vehicles on steep tracks and trails, or away from formed roads or trails  working near heavy equipment such as bulldozers When you are working in such situations, you must observe normal safe work practices to minimise risk of injury to yourself and others. You should:  keep a safe distance from other firefighters using handtools Version 1.1 November 2011
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 carry tools and equipment in the correct way.  never get on or off moving vehicles  step down, not jump from equipment or vehicles  never ride on bulldozers or other equipment not designed for carrying people  not work immediately in front of or behind a bulldozer, but rather to the side  be alert to rolling and falling materials Chainsaw Operations on the Fireground 
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Identify where the operator is, and ensure you know what the operator intends to do. Ensure that you maintain an appropriate distance from the operator, keeping in mind that you could be standing in the operators escape route. If the operator is felling a tree, identify where the tree is intended to be fallen. Be mindful that even a very experienced operator’s tree may not fall where intended. Identify the planned area for the tree falling, plan your escape route and be ready to move away if needed Driving on or near a Fire ground If driving on or near a fire ensure that all lights are on, this increases your vehicles visibility. Most fire grounds will have dust and smoke in the air, this can decrease visibility to nothing in seconds. If you have a need to stop park your vehicle to one side of the trail, this allows other vehicles to pass. Ideally try to park on the same side other vehicles around you have parked on. Parking off to the side also reduces the risk of a vehicle collision in an emergency evacuation as drivers know that vehicle will be on one side of the road. If you park near a fire, get out and have a quick look around at the trees near your vehicle, check to make sure the trees look safe. Once on the fire ground look around constantly to make sure your situation awareness is not lost. Look out for changes in wind direction, fire behaviour these may indicate that it is time for you to leave for a safer location. Version 1.1 November 2011
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3 Specific wildfire hazards Hazards which may be encountered on the fireground include:  heat stress  smoke  fatigue  electrical hazards  structural fire hazards  dangerous trees  changes in fire behaviour Heat Stress Personnel working on the fireground may experience some form of heat stress as a result of:  radiant heat from the flames  high temperatures normally experienced under summer conditions  high body temperature caused by strenuous work Heat stress can lead to heat exhaustion and, ultimately, to heat stroke which can be a life‐
threatening condition. The symptoms of heat exhaustion are:  cramps  clammy skin  feeling faint Version 1.1 November 2011
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 light headedness  dizziness  headaches  nausea The symptoms of heat stroke (a medical emergency) are:  dry, hot skin  disorientation, mental confusion  staggering and loss of co‐ordination  collapse  convulsions  loss of consciousness Where heat exhaustion or heat stroke is evident, you should follow these guidelines:  remove the affected person from further exposure to heat sources  loosen the person’s clothing to allow for the evaporation of perspiration  provide an adequate intake of fluids (small sips of water or weak cordial) at regular intervals WARNING When heat stroke is suspected, you must act quickly. This can be a life‐threatening condition. Seek medical assistance or report immediately to your Incident Controller or team leader. Version 1.1 November 2011
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How to avoid heat stress You can minimise heat stress by:  wearing the correct protective clothing in accordance with the relevant agency guidelines.  drinking lots of water  sharing heavy work loads  walking and not running  working at a comfortable distance from the fire  taking breaks when appropriate  avoiding unnecessary exposure to radiant heat Smoke Smoke is an ever‐present irritant at fires, but prolonged exposure to heavy smoke can be a hazard to personnel on the fireground. Smoke irritates eyes and lungs. In addition, heavy smoke contains carbon monoxide (CO) which is poisonous. Too much smoke and CO can:  reduce your performance on the fireground  bring on fatigue more quickly Minimise the effects of smoke by:  avoiding unnecessary exposure to it  using smoke masks and goggles, where provided, or if necessary, handkerchiefs or other cloth to cover your mouth and nose Version 1.1 November 2011
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NOTE In situations where there is heavy smoke, be aware that fresh air pockets may be found near the ground. Fatigue Firefighting can involve strenuous work for extended periods of time. Excessive fatigue will impair your performance and potentially put your life and that of others at risk. To avoid this:  pace yourself (that is, conserve energy)  make the maximum use of your rest breaks  ensure that you get adequate meals and maintain your fluid intake Version 1.1 November 2011
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Electrical Hazards Emergency responders attend a variety of incidents in which electricity may be involved. The main types of incidents are:  Downed electrical wires. These may occur as a result of events such as traffic accidents, storms, or wildfires  Pole top fires. These are fires involving electricity poles. They may be the result of birds or animals causing an arc; broken insulators; conductors becoming dislodged; or dust or salt building up on insulators and acting as a conductor in misty or light rain conditions. In situations where there is a pole fire, untrained emergency personnel must not make any attempt to extinguish the fire until the electricity has been switched‐off. In these situations, they should stand clear and wait till assistance arrives. To avoid exposure to an electric shock, you should remain at least eight metres away and where possible keep your feet together. This distance may need to be greater if the ground is contaminated by conducting agents such as water. REMEMBER – Always assume downed power lines are “Live” Structural Fire Hazards Community Fire Unit members must NOT enter a building involved in fire under any circumstances. The toxic smoke and fumes emitted from burning buildings can be fatal. You must remain upwind at a safe distance from building fires at all times. Version 1.1 November 2011
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Dangerous Trees Danger may come from the tree itself, the tree’s immediate surroundings, or the prevailing weather conditions. What makes a tree potentially hazardous? 
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Affected by fire Heavy decay Dead or partially dead Very brittle or have hollow trunks Crown overhanging roads at an angle Signs of fracture in trunk or branches Broken limbs hanging in the crown Excessive lean Tree is hung up or has a hanging tree resting on it Root ball exposed Burning internally Safety Zones Once a potentially hazardous tree has been identified by Pink Tape: 
A clear working area of two times the height and up to five times the height on the downhill side of steep slopes of potentially hazardous trees will be maintained. Changes in fire behaviour As previously discussed Chapter 2; fuel, weather and topography can all affect fire behaviour. Changes in fire behaviour can present significant risks. Some indicators of a potential blow up situation are: 
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Spot fires forming ahead of the main fire Increasing fire intensity High levels of fuel Rapid change in weather conditions Convergence Version 1.1 November 2011
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Convergence is when two or more fire fronts join or meet up. The area where fire fronts converge is referred to as the convergence zone, within which there is increased flame height and fire intensity. Fire convergence may eliminate escape routes. 4 Survival in life‐threatening situations When working on the fireground, you must avoid putting yourself at risk unnecessarily. Conditions on the fireground can alter quickly and can lead to significant changes in the overall fire situation. If you find yourself in a position where fire is threatening your immediate location, and escape is not possible, you must protect yourself from radiant heat. You can:  Shelter in a property identified as being safe and prepared  shelter in a vehicle  make sure that it is not adjacent to heavy fuels, wind up all windows, close vents and turn on headlights. When sheltering in a vehicle the vehicle may catch on fire, if you attempt to extinguish the fire do so as safely as possible. If fire is too large then stand back at a safe distance from the vehicle and report your location and condition immediately (see Figure 19)  shelter in refuges such as caves and hollows, running streams or other large bodies of water  dig or scrape out a refuge (the deeper, the better) and lay face down (see Figure 20)  shield yourself with whatever is available, such as woollen blankets or heavy coats Figure 19: Survival on the fireground Version 1.1 November 2011
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WARNING Remain calm and do not run blindly from the fire. Do not run uphill away from a fire unless you know a safe refuge is nearby. Do not attempt to run through flames unless you can see clearly behind them. Always have a plan for where you will shelter. Figure 20: Protecting yourself from an approaching fire Version 1.1 November 2011
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5 L.A.C.E.S. Remember the memory jogger LACES when on the fireground. 
Lookout 
Awareness 
Communication Maintain lines of communication and report any problems. Fire fighters maintain communications with all crew members and command. Any communication problems and black spot problems are reported. Ensure your instructions are clear. Escape Routes 
Monitor and lookout for changes in fuel condition, weather and topography that affect fire behaviour. Crew condition, work progress and other nearby crews and equipment must also be monitored. Safety gear is compulsory. 
A lookout must be assigned to a safe vantage point with communications to all crew members to specifically watch for hazards. Check for at least two escape routes and advise crew of these. Develop and communicate the decision trigger to activate an escape. Safety Zones Identify and work from an anchor point when possible. Select or construct a large enough area for anticipated conditions. Park your vehicle in a safe spot. Version 1.1 November 2011
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Also watchout when… 1. Building a control line downhill towards a fire 2. On a slope ‐ rolling material can ignite fuel below you 3. The wind changes speed or direction 4. The weather gets hotter or drier 5. There are unburnt fuels between you and the fire 6. Terrain or vegetation impedes travel or visibility 7. In country you have not seen in daylight 8. Unfamiliar with weather and local fire behaviour 9. Frequent spot fires occur over your control line 10. You cannot see the main fire or communicate with anyone who can 11. Unclear instructions or tasks are given 12. You feel exhausted or want to take a nap near the fire 13. Attacking a fire or constructing a fire‐control line without a safe anchorpoint 14. Working alone with no communications link to crew members or supervisor 15. You are not fully informed about strategy, tactics and hazards 16. Safety zones and escape routes have not been identified 17. The potential of the fire has not been assessed 18. Water levels are getting low Version 1.1 November 2011
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6 Communication Arrangements Australasian Inter‐agency Incident Management System (AIIMS) Structure AIIMS provides a management structure whereby the Incident Controller holds overall responsibility for managing all activities to control the incident. The Incident Controller is also responsible for managing the Incident Management Team. To manage an incident, the Incident Controller will establish a management structure designed to deliver the key functions of control, planning, operations, logistics and public information. The way in which these functions are managed will depend on the size and complexity of the incident. At a small incident, or during the early phases of what may become a large or complex incident, the Incident Controller may effectively manage all functions. As the incident develops in size or complexity, the Incident Controller may choose to delegate responsibility for managing these functions to other people. The management structure might eventually expand to have separate people and teams managing the delivery of each of the planning, operations and logistics functions The responsibilities of the Incident Controller are the same whether the consequences of the incident are of a minor or major nature. However, incident control becomes more of a managerial role as the structure expands and the functions of planning, operations, logistics and public information are delegated. Delegation of the Incident Controller's responsibilities to persons performing subordinate functions depends upon the type of incident, location, resources required, control, difficulties and assets at risk. Once the Incident Controller appoints a delegate to one of the functional positions, an Incident Management Team results. At all times, however, the Incident Controller retains the overall responsibility for management of the incident and for appointment and supervision of the Incident Management Team. A major benefit of AIIMS is that the management structure can grow as the incident develops. The Incident Controller develops a structure to match the incident by delegating responsibilities. To initiate this development, the Incident Controller needs to recognise the early warning signs of being unable to respond to requests effectively. Version 1.1 November 2011
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Incident Management Team Where all functions have been delegated, an Incident Management Team comprises the Incident Controller, the Operations Officer, Planning Officer, Logistics Officer and Public Information Officer. The Incident Management Team should meet as necessary, as determined by the Incident Controller, to assist the Incident Controller to ensure that control of the incident is being: 
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

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properly planned adequately resourced within the constraints of the agencies suitably implemented provides for the safety and welfare of people involved in controlling the incident minimises impacts on the community and the environment and is effective and efficient. Classification of Incident As incidents grow in size and/or complexity management becomes more demanding and the Incident Controller needs to consider the delegation of responsibility. In smaller incidents, the Incident Controller may have the capacity to undertake more than one role and delegate others. As an incident develops, the Incident Controller may elect to delegate additional functions to enable them to devote more attention to the control function. Level 1 Incident A Level 1 incident is characterised by being able to be resolved through the use of local or initial response resources only. In a Level 1 incident the major function is operations, which is to resolve the incident. Control of the incident is limited to the immediate area, and, therefore, the operations function can usually be carried out by the Incident Controller. Being relatively minor, the other functions of planning and logistics will, generally, be undertaken concurrently by the Incident Controller. Version 1.1 November 2011
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Level 2 Incident Level 2 incidents are more complex either in size, resources or risk. They are characterised by the need for: 
deployment of resources beyond initial response: OR 
sectorisation of the incident OR 
the establishment of functional sections due to the levels of complexity OR 
a combination of the above. Level 3 Incident Level 3 incidents are characterised by degrees of complexity that may require the establishment of Divisions for effective management of the situation. These incidents will, usually, involve delegation of all functions. Incident Action Plan (IAP) The strategic goals, tactical objectives, and support requirements for the incident. All incidents require an action plan. For simple incidents (Level I) the action plan is not usually in written form. Large or complex incidents (Level II or III) will require that the action plan be documented in writing.
SMEACS SMEACS is a common format used for Incident Action Plans and Incident briefings. Pro forma’s utilizing this format are available from the relevant agencies. Before entering afire ground personnel must receive a briefing. Briefings usually commence with an introduction of the personnel conducting the briefing and an explanation of the purpose of the briefing. The SMEACS format covers the following points: 
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Situation – this is an overview of the incident Mission – this covers the incident objectives Execution ‐ this covers sectorisation, strategies and tactics Version 1.1 November 2011
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Administration – this covers administration and logistics Command and Communication – this covers the Incident Management structure and the communications plan Safety – this covers weather, known and anticipated hazards, situations to be aware of, safety equipment including PPE and welfare issues (hydration, first aid) Individual sectors or units may have their own IAP’s but these must align to the overall objective/s. It is vital for effectiveness and safety that there is a single overarching Incident Action Plan and that a single chain of command is established with a supporting communications plan. All personnel must be working to the same objective and maintain two‐way communication within a command structure which ensures maintenance of effective and pure communications and decision‐making. At a minimum; non‐fire personnel entering a fire ground must receive a safety and communications briefing. Ensure that you are aware of: 
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

The chain of command and communications plan How to make a call and activate the duress alarm on the radio system Escape routes The evacuation decision trigger and the emergency warning protocols (could be a radio message such as ‘red, red, red’ or a blast of a horn) and action to be taken on hearing these. If emergency warning protocols are activated – take action immediately. Version 1.1 November 2011
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7 Personal Protective Equipment Your personal protection at an incident is of paramount importance. An emergency worker injured or becoming ill whilst working on the incident ground is a potential liability. Injured or unwell emergency workers may place themselves and other crew members in danger. The design and fabrics used in protective clothing are particularly important because unsuitable clothing can create a heat stress problem. The seriousness of the problem can range from discomfort to impaired performance, illness, collapse and even death. Protective clothing can also restrict you in the performance of your task by adding weight and limiting movement. The purpose of this document is to provide information on the Selection Care and Use of Personal Protective Clothing (PPE) for use by members of the ACTF&R Community Fire Units (CFU). All PPE worn by ACT firefighters including CFU members is manufactured in accordance with the most appropriate Australian or International Standard. It is important to remember that along with your training, your PPE is the first line of defence to prevent serious injury or even death. All PPE must be kept clean and well maintained at all times if it is going to provide you with the protection it is designed for. The following information will assist you with understanding the many facets of your PPE: Selection 
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Composition and compliance When to wear your PPE How it should be worn Maintenance Repairs or replacement Version 1.1 November 2011
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The function of PPE is to protect the firefighter whilst enabling them to achieve their objectives. In addition, in emergency situations where it is impossible to achieve the objectives, the PPE should safeguard the firefighter allowing him or her to escape to a place of safety. The PPE is manufactured to specific standards that provide levels of performance requirements for all firefighters. This enables the above mentioned criteria to be met with the levels selected being based on a risk assessment. Bushfire Helmet The Tuffmaster bushfire helmet is manufactured in compliance with AS/NZS 1801 Type 3 Occupational Protective Helmets For Bushfire. The helmet has an adjustable harness, neck protector and chinstrap. The helmet is designed to absorb the energy of a blow by partial destruction or damage to the shell and harness; the helmet is also designed to provide protection from radiant heat from a bushfire environment. Version 1.1 November 2011
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Bushfire Goggles The Uvex bushfire goggles are manufactured in compliance with AS/NZS 1337 1992 and AS/NZS 1338 1992. These goggles are designed specifically for bushfire fighting. Bushfire Coat and Trousers The bushfire coat and trousers are manufactured in compliance with AS 4824 Protective Clothing Used For Wildland Firefighting. The garments are made of a Proban or simular treated cotton and with the flame retardancy of the fabric complying with the requirements of EN 531 Para 6.2.2 after 50 washes at75° C (ISO10528). Version 1.1 November 2011
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Bushfire Gloves The Firepro Wildfire Gloves are manufactured in compliance with AS 2161.6 Protective Gloves For Firefighting. The gloves have a high wear leather outer shell and a fire resistant proban double ribbed cuff designed specifically for bushfire fighting. Bushfire Boots The Taipan bushfire boot is manufactured in compliance with AS/NZS 4821 2002 Protective Footwear For Firefighting. The boot is a fully lined leather boot incorporating a toecap; it has a high resistance to heat and has non‐ flammable laces. Version 1.1 November 2011
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Bushfire Disposable Face Masks The Tornado P1 mask is manufactured in compliance with AS/NZS 1716. The mask has an exhalation valve and is classified as “P1 nuisance level odour removal”. Version 1.1 November 2011
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Members of the CFU MUST wear protective clothing and other items of PPE when carrying out bushfire fighting activities. If you have not been issued with CFU PPE, you can still protect yourself by wearing the following appropriate clothing which includes long pants, long sleeve shirts, sturdy boots and gloves. A photo of typical clothing is shown below: Version 1.1 November 2011
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SUMMARY 
To minimise injury to yourself and others, you should observe safe work practices at all times. This includes operating equipment and vehicles correctly and taking care when working near
heavy machinery. 
Hazards encountered on a fireground vary but some of the more common ones include heat
stress, smoke and fatigue. 
Heat stress can occur as a result of radiant heat, high temperatures and strenuous activity. 
The symptoms of heat exhaustion include cramps, clammy skin, headaches and nausea. 
Heat stroke is a serious condition that requires medical attention. 
Heat stress can be avoided by wearing the correct clothing and by an adequate intake of
fluids. 
The effects of smoke can be minimised by wearing masks and goggles, and by reducing the
amount of unnecessary exposure. 
Fatigue can be minimised by pacing activities, taking rest breaks, eating correctly and
maintaining fluid intake. 
If faced with a life‐threatening situation, protect yourself from radiant heat. 
Remember the memory jogger L.A.C.E.S when on the fireground. Lookout, awareness, communications, escape routes and safety zones. 
The Australasian Inter‐agency Incident Management System (AIIMS) provides a structure for managing all activities to control the incident. 
Before entering a fireground personnel must receive a briefing. Version 1.1 November 2011
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Indicate whether the following statements are true or false:
T F 1. When working near heavy equipment, you should stay to the side, not behind
or in front. Self‐check questions 2. You should never get on or off moving equipment.
3. Heat stress can lead to heat exhaustion if not checked. 4. Symptoms of heat stroke include dry, hot skin, disorientation, staggering and
loss of co‐ordination. 5. If heat stroke or exhaustion is evident, you should simply remove the person
from further exposure to heat and wait till the person feels better. 6. Heat stress can be avoided simply by drinking lots of fluids.
7. Exposure to excessive smoke brings on fatigue more quickly.
8. In situations where there is heavy smoke, fresh air pockets can be found near
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9. Adequate food and fluid intake help to minimise fatigue.
10. You should never attempt to out run a fire or to run through flames unless you
can see clearly behind them. 11. Lines of communication must be maintained at all times and any problems
reported. 12. One escape route must be available
13. AIIMS is a management structure which can grow as the incident develops.
14. Where all functions have been delegated the Incident Management Team
comprises the Incident Controller and the Logistics Officer. 15. Non‐fire personnel entering a fireground must receive a safety and communications briefing. Check the answers section at the back of this manual to see how you
went. Version 1.1 November 2011
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Chapter 6 Aircraft at wildfires 1 Introduction This chapter covers the various uses of aircraft at a wildfire, the safety precautions you should take when working in and around aircraft, and what to do in an inflight emergency situations and if you are caught in a firebombing zone. A range of aircraft is used in wildfire suppression activities. The uses of aircraft at an incident can vary widely. The main uses are: 
fireground command and control 
detecting fires 
applying water or aerial retardants (that is, firebombing) 
igniting backburns 
transporting crews and equipment 
observing and mapping fires using infra‐red equipment and other technology 
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2 Safety precautions When working in and around aircraft, there are general safety principles that apply. You should observe these precautions at all times: 
always follow the directions given by the pilot, flight crew or aircraft co‐ordinator 
wear correct eye, ear and head protection when working on or near an airstrip or helipad. Do not wear loose head gear, for example, a baseball cap 
stand clear of landing and take off areas and do not smoke within 30 metres of an aircraft or refuelling equipment 
be aware of propellers and rotors, particularly when engines are idling, during warm up and brief stops. Never lean on them as this may cause the engine to turn over and cause injury 
do not handle moving parts such as flaps, aerials and airspeed sensing tubes as these can be easily damaged 
when boarding or leaving aircraft, be careful to avoid using panel areas marked “No Step” 
assist with loading equipment or materials only under the supervision and guidance of the pilot, as the pilot is responsible for the correct weight and balance of the aircraft 6 What to do if caught in a firebombing drop zone Firebombing is a term used to describe the dropping of water, foam or retardants in wildfire suppression activities. Firebombing activities are usually carried out by helicopters or fixed‐
wing, agricultural type aircraft. If caught in a firebombing zone: 
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
do not run or panic 
watch out for dead or suspended branches 
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place hand tools well clear of you hold helmet on or protect head with arms watch your footing wash with cold water if hit with foam or retardant Version 1.1 November 2011
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SUMMARY 
Aircraft are used for the following purposes: fireground command and control detecting fires applying aerial retardants igniting backburns transporting crews and equipment observing and mapping fires using infra‐red equipment and other technology aircraft management, for example, bomber co‐ordination and drop procedures. 
Safety principles when working around aircraft require firefighters to: wear the correct personal protective clothing and equipment follow instructions given by the pilot and flight crew. 
Do not: smoke handle (or mishandle) aircraft equipment. 
Do: approach, board and disembark from the aircraft in the correct manner carry equipment in the correct manner to avoid personal injuries or damaging the aircraft. 
While travelling in aircraft, firefighters must follow the instructions given by the pilot and
flight crew. 
In an emergency situation, follow the appropriate procedures for bracing yourself. 
In a firebombing drop zone, foams and retardants are used for suppression activities. If in a
firebombing zone, follow correct procedures. If splashed with retardant, wash exposed areas
with cold water as soon as possible. Version 1.1 November 2011
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Indicate whether the following statements are true or false:
T F 1. Aircraft are used for detecting fires, transporting crews and equipment, and for
igniting backburns. Self‐check questions 2. If caught in a firebombing zone, move away from the fire line.
Check the answers section at the back of this manual to see how you
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Answers to self‐check questions Chapter 1 Fire 1. T 5. T
9.
T
13.
F 2. F 6. F
10.
F
14.
T 3. T 7. F
11.
F
15
F 4. T 8. T
12
T
Chapter 2 Factors which affect wildfire behaviour
1. T 5. T
9.
T
13.
F 2. T 6. F
10.
F
14.
F 3. T 7. T
11.
T
4. F 8. T
12.
T
Chapter 3 Wildfire development
1. F 4. T
7. F
2. F 5. T
8. F
3. T 6. T
9. T
10. T Version 1.1 November 2011
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Chapter 4 On the fireground
1. T 3. T
5.
T
2. T 4. T
6.
F
7. T Chapter 5 Safety on the fireground
1. T 5. F
9. T
13. T 2. T 6. F
10.. T
14. F 3. T 7. T
11. T
15. T 4. T 8. T
12. F
Chapter 6 Aircraft at wildfires
1. T 2. T Version 1.1 November 2011
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Glossary Adaptor A fitting used to couple different sized hoses, hoses of the same size with different threads, or different types of couplings, or to connect the male to male, or female to female parts of the same type of coupling. AFAC The Australasian Fire Authorities Council is the national body representing urban, rural and land management agencies within Australia and New Zealand with the responsibility for the protection of life and property from fire and other emergencies. Appliance A firefighting vehicle, usually equipped with a pump and water supply. Backburning A fire ignited along the inner edge of a control line to consume the fuel in the path of a wildfire. Blackout Complete extinguishment of all burning material in a given area (see mop‐up) Branch An attachment fitted to the end of a hose to speed up the water to form an effective jet or spray pattern. Breeching A device to divide one hose line into two or collect two hose lines into one. Version 1.1 November 2011
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Bushfire A general term used to describe a fire in vegetation. Chemical chain reaction This is the fourth dimension of the fire tetrahedron. (see Fire tetrahedron). Combustion Rapid chemical combination accompanied by heat and usually light. It is the process of burning. Competency Skills and knowledge and their application within an occupation to the standard of performance required in the workplace. Contained A fire is contained when its spread has been halted, but it may still be burning freely within the perimeter or control lines. Control line (fire line) A natural or constructed barrier, or treated fire edge, used in fire suppression and prescribed burning to limit the spread of fire. Controlled The time at which the complete perimeter of the fire is secured and no breakaway is expected. Crew The basic unit of a fire suppression force, normally consisting of 5‐10 personnel. Version 1.1 November 2011
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Crown fire A fire which burns in the crowns of trees ahead of and above an intense fire in the undergrowth. A fast‐travelling fire that is most destructive and usually consuming all available fuel in its path. Defensive strategy A firefighting strategy used in wildfire situations where the fire is too remote or too intense to be safely or effectively attacked or extinguished. Delivery hose Hose made in various diameters of fabric construction and used to transport water under pressure. Delivery hose may or may not be internally lined with rubber or plastic. Direct attack A method of wildfire attack where wet or dry firefighting techniques are used. It involves suppression action right on the fire edge which becomes the control line. Draughting Relates to static water supplies, and is the action of removing the air from the suction hose and pump casing to create a vacuum. Atmospheric pressure then forces water up the hose and into the pump to replace the vacuum, enabling the pump to deliver water. Driptorch A canister of flammable fuel fitted with a wand, a burner and a fuel flow control device. It is used for lighting fires for prescribed burning and backburning. Dry firefighting The suppression of a fire without the use of water. This is normally achieved by removing the fuel, by the use of hand tools or machinery. Version 1.1 November 2011
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Energy Source of power which may be released in forms such as heat, light and movement. Fingers Narrow slivers of the advancing wildfire which extend beyond the head or flanks. Fire danger Summation of all factors determining whether fires will start, spread and do damage and whether and to what extent they can be controlled. Fire tetrahedron An instructional aid in which the sides of the tetrahedron (comprising four triangular shaped figures) are used to represent the four components of the combustion and flame production process fuel, heat, oxygen and the chemical chain reaction. Fire triangle A figure illustrating the three components necessary for a fire to burn and continue to burn oxygen, heat and fuel. Firebombing A technique of suppressing a wildfire by dropping water, foam or retardants on it from an aircraft. Fixed‐wing aircraft A heavier than air aircraft which obtains lift for flight by forward motion of wings through the air. Flank attack Obtaining control of a fire by attacking its sides (flanks). Version 1.1 November 2011
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Flanks Those parts of a fire’s perimeter that are roughly parallel to the main direction of spread. Foam Foam is the aerated solution created by forcing air into a water solution containing a foam concentrate. Foam ‐ Class A A firefighting agent produced by adding Class A concentrate to water and passing it through a foam or spray nozzle. Class A foam is more effective and more persistent than plain water. Forest fire A fire burning mainly in forest and / or woodland. Fuel Any material such as grass, leaf litter and live vegetation which can be ignited and sustains a fire. Fuels can be categorised as fine or heavy and are usually measured in tonnes per hectare. Ground fire A fire burning in thick layers of humus and vegetation, found in forest or swampy ground or peat. Head attack Directly knocking down the head of a fire. Recommended only for low intensity fires where firefighters can be sure that the fire will not flare up unexpectedly. Version 1.1 November 2011
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Head of the fire The part of the fire where the rate of spread, flame height and intensity are greatest, usually when burning downwind or upslope. Heavy fuels Dead woody material, greater than 6mm in diameter, in contact with the soil surface (fallen trees and branches). Heel, rear or back The section of the perimeter opposite to and generally upwind (or downslope), from the head of the fire. Hot Spot A particularly active part of the fire (usually on an edge). It is usually associated with heavy fuel. Ignition The process for starting combustion. Indirect attack The use of backburning as a method of suppression to confine the fire within a defined area bounded by existing or prepared control lines. Control lines may be a considerable distance ahead of the fire. Industry and specified standards Competency standards which have been developed specifically for an industry. Initial Attack The first suppression work on a fire. Version 1.1 November 2011
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Knock down The rapid application and concentration of water or foam, intended to reduce fire intensity prior to manual follow‐up action. Mineral earth A term used to describe the ideal condition of a constructed firebreak, being completely free of any vegetation or other combustible material. Mop up (see blackout) To make a controlled fire safe, by extinguishing or removing burning material along or near the control line, felling stags, trenching logs to prevent rolling and the like. Nozzle A fitting that is used with a branch to control the size, pattern and/or velocity of water or extinguishing medium being discharged. A separate nozzle may be fitted to the end of a branch, or the branch and nozzle may be a combined unit. Offensive strategy A firefighting strategy used in wildfire situations where the fire can safely and effectively be attacked or extinguished. One‐lick method A method for a team of firefighters to construct a firebreak in which each firefighter in line removes part of the vegetation as they move along, so that all of it has been removed once the team has passed along. Oxygen Colourless, odourless gas, making up about one fifth of the volume of the atmosphere. It is the supporter of combustion in the air. Version 1.1 November 2011
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Parallel attack A method of suppression in which a fire line is constructed approximately parallel to and just far enough from the fire edge to enable firefighters and equipment to work effectively. The line may be shortened by cutting across unburnt fingers. The intervening strip of unburnt fuel is normally burnt out as the control line proceeds Patrol 1. To travel over a given route to prevent, detect and suppress a fire. 2. To go back and forth vigilantly over a length of control line during and/or after construction, to prevent breakaways, to control spot fires, and extinguish overlooked hot spots. 3. A person or group of persons who carry out patrol activities. Perimeter The entire outer boundary of a fire area. From the point of view of attack, it is important to know which part of the perimeter is burning rapidly and which is burning slowly. Point of origin The location at which the fire started. Portable dam A temporary water storage used in conjunction with power pumps and hose lines. Primer A device used to remove air from a pump casing and suction hose line so that atmospheric pressure can force water, from a dam, pond, creek or river, up the hose into the pump. Pulaski tool A hand tool used for wildfire fighting consisting of a combination of a hoe and an axe. Version 1.1 November 2011
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Pumper A firefighting vehicle equipped with large capacity pump, water tank and hose. Generally intended to be operated when stationary, from reticulated or static water supplies. Quickfill pump High volume pump. Rakehoe/McLeod tool A hand tool used for wildfire fighting, consisting of a combination of a heavy rake and hoe. Rate of spread The speed of expansion of the perimeter of a fire. Forward rate of spread relates to the movement of the head fire. Rear / heel / back The section of the perimeter opposite to and usually upwind or downslope from the head of the fire. Relative humidity The amount of water vapour in a given volume of air, expressed as a percentage of the maximum amount of water vapour that the air can hold at that temperature. Relief crew Replacement personnel for those whose period at the fire has reached an end. Rotary wing aircraft Aircraft which obtain lift for flight by the rotation of rotors through the air. Helicopters are an example. Version 1.1 November 2011
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Scrub fire A fire burning in land of low economic value from a forestry point of view. Spot fires Isolated fires started ahead of the main fire by sparks, embers or other ignited material, sometimes to a distance of several kilometres. Spotting The ignition of spot fires from sparks or embers. Standard operating procedures A set of organisational directives that establish a standard course of action on the fireground to increase the effectiveness of the firefighting team. They are written, official, applied to all situations, enforced and integrated into the agency’s management of incidents. Step‐up method A method used by a team of firefighters to construct a firebreak in which each firefighter completely constructs a section of the firebreak after which the entire team "steps up" to the next section. Suction hose Hoses, made in various diameters, of reinforced rubber or plastic, used to draft water out of ponds, dams, creeks, tanks or rivers. Staging area A location close to the incident where personnel and equipment are available. Strike Team A set of resources of the same type that have an established minimum number of personnel. Strike teams always have a leader (usually in a separate vehicle), and have a common Version 1.1 November 2011
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communications system. Strike teams are usually made up of five resources of the same type such as vehicles, crews and earth moving machinery. Surface fire A fire which travels just above ground surface in grass, low shrubs, leaves and forest litter. Tanker A mobile rural firefighting vehicle equipped with water tank, pump and hoses. Taskforce A combination of resources that can be assembled for a specific purpose. Task forces usually have a leader (usually in a separate vehicle), and have a common communication system. Task forces are established to meet tactical needs and may be demobilised as single resources. Tongue Long narrow fingers of advancing fire which extend beyond the head or flanks. Topography The surface features of a particular area or region. It may include mountains, rivers, populated areas, roads and railways and fuel types. Under control When complete perimeter is safe and no breakaway is expected. Wetting agent A chemical added in low concentration to water. It is used in firefighting to break down the surface tension of the water and improve its penetration into fuels. Wildfire An unplanned fire. A generic term which includes grass fires, forest fires and scrub fires. Version 1.1 November 2011
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