Which foam application technique is the primary manual application technique used on aboveground storage tank fires?
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This preview shows page 7 - 10 out of 14 pages. The reaction acts against both the nozzle and the curves of the hoseline, making itdifficult to handle*One person can usually operate a smooth bore nozzle on a 1½” or smaller hoseline Shiroma ifsta 20161¾” or larger hoseline require additional personnel to overcome the reaction of thehose.*as the fog patterns widens, the reaction decreases making the nozzle easier tohandlenozzles should be inspected after each use and at least annually.It should be alsocleaned after each use to prevent the build-up of contaminantsFIRE FIGHTING FOAM- works by forming a blanket of foam on the surface of burningfuels, both liquid and solids.FOAM extinguishes fires by (separating, cooling, smothering, penetrating)Separating- creates a barrier between the fuel and the fireCooling- lowers the temp. of the fuel and adjacent surfacesSmothering- prevents air from reaching the fuel and mixing with the vapors andprevents the release of flammable vapors. (reduces the possibility of reignition)Penetrating- lowers the surface tension of water and allows it to penetrate fires inclass A materialsOn solid fuels, class A foam blankets and cools the fuel and stops the burningprocess.After controlling the flames, the water in the foam is slowly released intothe fuel process as the foam breaks down.This action provides a cooling effect onthe fuel.Class a works by penetrating the fireOn class B liquid fuels, the class B blanket also prevents or reduces the release offlammable vapors from the surface of the fuel.Class B foam is especially effective onthe 2 basic categories of flammable liquids (hydrocarbons, polar solvents).Class Bfoam works by suppressing vapors, separating the fuel from the fire, cooling the fueland other surfaces, and smothering flaming combustion.Foam concentrate- chemical compound solution that is mixed with water and air toproduce finished foamFoam proportioner-device that introduces foam concentrate into the water streamto make the foam solutionFoam solution- mixture of foam concentrate and water before the introduction of air.Finished foam- completed product after air is introduced into the foam solutionAeration is needed to produce quality foam bubbles, and produces uniform-sizedbubbles that produce a linger lasting blanket.Foam expansion- refers to increase in volume of a foam solution when it is aerated,result of adding foam solution consisting of water and foam concentrate.Foam expansion depends on (type of foam, proportioning, quality of concentrate,method) Shiroma ifsta 2016There are 3 classifications of foam based on their expansion ratio (low, medium,high)Low expansion- 20:1 ratio, effective for controlling most Class B fires and coolingand penetrating Class A firesMedium expansion- 20:1- 200:1, delivered through a hydraulically operated nozzlestyle delivery devices.Used to suppress vapors from hazardous materials spillswhen applied at expansion rates of 30:1-55:1. Upload your study docs or become a Course Hero member to access this document Upload your study docs or become a Course Hero member to access this document End of preview. Want to read all 14 pages? Upload your study docs or become a Course Hero member to access this document Presentation on theme: "Chapter 14 Lesson Goal After completing this lesson, the student shall be able to effectively apply fire fighting foam using various foam types, concentrates,"— Presentation transcript: 0 Essentials of Fire Fighting, 5th Edition 1 Chapter 14 Lesson Goal After completing this lesson, the student shall be able to effectively apply fire fighting foam using various foam types, concentrates, and delivery devices following the policies and procedures set forth by the authority having jurisdiction
(AHJ). Firefighter II 2 Specific Objectives 1. Describe the suppression characteristics of fire fighting foam. 2. Define terms associated with types of
foam and the foam-making process. 3. Discuss how foam is generated. (Continued) Firefighter II 3 Specific Objectives 4. Discuss foam concentrates. 4 Specific
Objectives 8. List reasons for failure to generate foam or for generating poor-quality foam. 9. Describe foam application techniques. (Continued) Firefighter II
5 Specific Objectives 10. Discuss hazards associated with foam
concentrates. 11. Place a foam line in service — In-line eductor. (Skill Sheet 14-II-1) Firefighter II 6 Ways Fire Fighting Foam Extinguishes/Prevents Fire 7 Terms Associated With Foam
8 How Foam is Generated Foams used today are of mechanical type and before use must be Proportioned Aerated (Continued)
Firefighter II 9 How Foam is Generated Elements needed to produce fire fighting foam 10 How Foam is Generated All elements must
be present and blended in correct ratios Aeration produces foam bubbles to form effective foam blanket Firefighter II 11 Foam Expansion The increase in volume of foam when aerated 12 Foam Concentrates — General Considerations
13 Class A Foam Increasingly used in both wildland and structural fire fighting Special formulation of hydrocarbon
surfactants (Continued) Firefighter II 14 Class A Foam Aerated
Class A foam coats, insulates fuels, preventing pyrolysis and ignition May be used with variety of nozzles Firefighter II 15
Class B Foam Used to prevent ignition of or extinguish fires involving flammable and combustible liquids Used to suppress vapors from unignited spills of these liquids Several types of Class B foam concentrates available (Continued) Firefighter II
16 Class B Foam Manufactured from synthetic or protein base 17 Class B Foam Foams such as AFFF and FFFP foam may be applied with standard fog nozzles or air-aspirating foam
nozzles Rate of application depends on several factors (Continued) Firefighter II 18 Class B Foam Unignited spills do not require same
application rates as ignited spills To be most effective, blanket of foam 4 inches (100 mm) thick should be applied to fuel surface Firefighter II 19 Specific Application Foams 20 Proportioning Mixing of water with foam concentrate
to form foam solution Most concentrates can be mixed with fresh/salt water (Continued) Firefighter II 21
Proportioning For maximum effectiveness, foam concentrates must be proportioned at designated percentage Most fire fighting foams intended to be mixed with 94 to 99.9 percent water Firefighter II 22 Proportioning Methods 23 Foam Proportioners — General Considerations 24 Portable Foam Proportioners
25 Apparatus-Mounted Proportioners
26 Compressed-Air Foam Systems (CAFS)
27 Compressed-Air Foam Systems (CAFS) 28 Compressed-Air Foam Systems (CAFS)
29 Handline Nozzles Solid-bore nozzles Fog nozzles
30 Medium- and High-Expansion Foam Generating Devices 31 Reasons for Poor-Quality Foam/ Failure to Generate Foam 32 Reasons for Poor-Quality Foam/ Failure to Generate Foam 33 Reasons for Poor-Quality Foam/ Failure to Generate
Foam 34 Roll-On Foam Application Method 35 Roll-On Foam Application Method 36 Bank-Down Foam Application Method 37 Bank-Down Foam Application Method 38 Rain-Down Foam Application Method 39 Rain-Down Foam Application Method
40 Foam Hazards to Humans Foam concentrates pose minimal health risks to humans May be mildly irritating to skin, eyes
(Continued) Firefighter II 41 Foam Hazards to Humans Affected areas should be flushed with water 42 Foam Hazards to Equipment
43 Foam Hazards to Environment
44 Foam Hazards to Environment
45 Foam Hazards to Environment
46 Summary Firefighters must know the differences between the classes of foam, how to generate
foam, and how to apply foam most effectively Firefighter II 47 Review
Questions 1. What are the ways that fire fighting foam extinguishes and/or prevents fire? 2. Describe types of foam concentrates. 3. What are the methods by which foam may be proportioned? (Continued) Firefighter II
48 Review Questions 4. What are the types of portable foam proportioners and how do they work?
5. Describe the techniques used to apply foam. Firefighter II Which type of foam is used to extinguish fires involving flammable and combustible liquids?Unlike other extinguishing agents - water, dry chemical, CO2, etc., a stable aqueous foam can extinguish a flammable or combustible liquid fire by the combined mechanisms of cooling, separating the flame/ignition source from the product surface, suppressing vapors and smothering.
Which type of foam is best used on wildland fires?Class A Foam: Used to extinguish Class A materials, such as wood, paper, and brush (wildland), is widely used by many fire departments for structural firefighting using compressed air foam systems.
Which is the most common type of foam proportion are used in the fire service?In-Line Foam Eductors
The in-line eductor is the most common type of foam proportioner used in the fire service (Figure 3). This eductor is designed to be either directly attached to the pump panel discharge or connected at some point in the hose lay.
What class of foam is used on flammable liquid fires?Class B firefighting foams serve a vital role in protection against flammable liquid fires. At the same time these foams contain ingredients such as fluorosurfactants that can impact the environment.
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