Rescue Technician Trench Rescue Operations

Transcription

1 Note Taking Guide Rescue Technician Trench Rescue Operations Maryland Fire and Rescue Institute University of Maryland Steven T. Edwards Fall 2009 Copyright 2009 by the Maryland Fire and Rescue Institute. All rights reserved. No part of this book may by copied or reproduced in any form or by any means without written permission of the Maryland Fire and Rescue Institute.

2 The Maryland Fire and Rescue Institute of the University of Maryland is the State s comprehensive training and education system for all emergency services. The Institute plans, researches, develops, and delivers quality programs to enhance the ability of emergency service providers to protect life, the environment, and property.

3 Trench Rescue Operations Lesson 1-1 Introduction to Trench Rescue Student Performance Objective Given information from discussion, handouts, and reading materials, describe trench rescue operations. The student will perform to a written test accuracy of at least 70% and successfully complete the skills on a skills check-off sheet. RES 206-PPT Overview Technical Rescue Disciplines The Big Three The Specialized Training Cycle Service Levels Additional Requirements for Certification Levels RES 206-PPT

4 Overview The Risk-Benefit Analysis The FAILURE Acronym Types of Service Levels The Team Getting Your Equipment to the Scene RES 206-PPT Overview OSHA Subpart P Excavations, 29 C.F.R General Requirements of Trench Rescue OSHA and Trench Rescue Trench Collapse Emergencies RES 206-PPT Overview The Trench Incident Management System Levels of the Incident Management System Logistics Support Functions RES 206-PPT

5 Technical Rescue Disciplines Technical Rescue Disciplines Trench rescue Rope rescue Vehicle and machinery rescue Swift water rescue Confined space rescue Structural collapse rescue RES 206-PPT The Big Three Special people are Different from traditional fire and rescue service providers Expected to operate in dangerous environments Expected to think clearly in dire situations Required to participate in intense training RES 206-PPT The Big Three Special equipment is Vitally important to the rescue effort Required to do the job safely and effectively Specialized and highly technical Difficult to maintain Expensive to operate RES 206-PPT

6 The Big Three Special training must be Solid, realistic, and practical Done often RES 206-PPT The Specialized Training Cycle Continuous recruitment, skill development, and equipment evaluation and updates RES 206-PPT Service Levels Awareness responders are Able to identify hazards and dangers Able to use a decision-making matrix Not actively involved in the rescue operation Educated to avoid being part of the problem RES 206-PPT

7 Service Levels Operations responders Are at the lowest level of certification May be responsible for initial and long-term rescue operations Are called support personnel May place sheeting or shoring systems in some trenches May function as sector officers RES 206-PPT Service Levels Technician responders have Additional trench rescue training Additional responsibilities Technical rescue skills package training RES 206-PPT Service Levels Instructors Have received certification Are certified in course development Should be active rescue team members RES 206-PPT

8 Additional Requirements for Certification Levels NFPA 1670, Chapter 11 Awareness Trench rescue awareness Confined space rescue awareness RES 206-PPT Additional Requirements for Certification Levels Operations Trench rescue operations Rope rescue operations Vehicle and machinery rescue operations RES 206-PPT Additional Requirements for Certification Levels Technician Trench rescue technician Confined space technician Vehicle and machinery rescue technician RES 206-PPT

9 Additional Requirements for Certification Levels NFPA 1006, Chapter 8 Job performance requirements Knowledge, skills, and abilities for fire service personnel who perform trench rescue operations RES 206-PPT Additional Requirements for Certification Levels RES 206-PPT The Risk-Benefit Analysis Is this a rescue or a recovery? What is the risk to the rescuer? What is the benefit to the situation? What is the difference between head versus heart decision making? RES 206-PPT

10 The FAILURE Acronym F Failure to understand the environment A Additional medical implications not considered I Inadequate rescue skills L Lack of teamwork and experience U Underestimating the logistical needs of the operation R Rescue recovery mode not considered E Equipment not mastered RES 206-PPT Types of Service Levels The self-sufficient team Commits to many hours of training Must have a considerable amount of specialized equipment Must have a means of transporting the specialized equipment Is the most expensive method of service RES 206-PPT Types of Service Levels The community-dependent team utilizes Those with construction and excavation experience A call-back list A logistical needs and supply list RES 206-PPT

11 Types of Service Levels The regional approach team Is the most cost effective Spreads the cost over several jurisdictions Requires written mutual aid agreements Is very hard to organize and maintain RES 206-PPT The Team The team members must be: Physically fit Mentally fit The team must have: Members that are proficient in construction skills Medical personnel as members People that think on their feet People in the best positions for their abilities RES 206-PPT Getting Your Equipment to the Scene A squad truck A dump truck or a flat-bed vehicle A trailer configuration A custom or converted vehicle A pod system A rescue truck RES 206-PPT

12 Getting Your Equipment to the Scene RES 206-PPT OSHA Subpart P Excavations, 29 C.F.R Provides data and information on appropriate protective systems Can be universally applied in a rescue situation Provides the requirements to qualify the user as a competent person Was originally part of the Contract for Hours Worked Standard Act RES 206-PPT The General Requirements of Trench Rescue Are the same as the guidelines used in construction operations Include rescue safety and operational guidelines Protection exceptions: All trenches must be protected before entry except Those made entirely of stable rock Those less than five feet in depth RES 206-PPT

13 The General Requirements of Trench Rescue Protection: Any trench five feet deep or more must be protected (may include the height of the spoil pile) Spoil pile: must be set back two feet from the lip Egress: Trenches 4 feet deep or greater in depth must have a means of egress every 25 feet RES 206-PPT The General Requirements of Trench Rescue Atmospheric hazards: All trenches should be tested for Oxygen deficiency or enrichment Hazardous atmosphere Flammable gases RES 206-PPT The General Requirements of Trench Rescue Water accumulation: employees need to be protected from water by dewatering operations and/or a lifeline A competent person must be able to determine the soil classification RES 206-PPT

14 The General Requirements of Trench Rescue Inspection: A competent person must inspect the trench for the following Secondary cave-in potential Protective systems failure Atmospheric monitoring or control Other hazardous conditions RES 206-PPT OSHA and Trench Rescue OSHA requires compliance under certain conditions An employee/employer relationship exists Trench rescue operations are part of your job You are paid for your service RES 206-PPT OSHA and Trench Rescue OSHA s view of trench rescue operations Trench rescue operations tend to overengineer protective systems Rescue protective systems are used for hours, not days Rescue operations have a different mission than construction OSHA will get involved in the operation for certain reasons RES 206-PPT

15 Trench Collapse Emergencies Emergencies due to noncompliance Accidents without a cave-in Medical emergency Trauma emergency RES 206-PPT Trench Collapse Emergencies RES 206-PPT Trench Collapse Emergencies Equipment failure and load management A backhoe- or excavator-caused problem Hydraulic failure Rigging failure Protective system failure Utility failure RES 206-PPT

16 Trench Collapse Emergencies RES 206-PPT Trench Collapse Emergencies Atmospheric concerns Include buried hazardous materials Require monitoring of the atmosphere Require situational awareness More than one ill victim in a trench One or more victims down in a trench May require a hazmat team response RES 206-PPT The Trench Incident Management System Is like any other IMS Requires an incident commander Decreases the organizational span of control Provides on-scene accountability Is dependent on the magnitude of the problem and the number of resources RES 206-PPT

17 The Trench Incident Management System RES 206-PPT Levels of the Incident Management System The strategic level: The Incident Commander Is responsible for developing the strategic goals for the operation Is responsible for all resources RES 206-PPT Levels of the Incident Management System The safety officer Is able to spot unsafe acts Is able to anticipate activities which will lead to accidents Is able to control the big picture Is familiar with the environment and its potential hazards Conducts pre-operational briefings RES 206-PPT

18 Levels of the Incident Management System The liaison officer Handles multiple agency interaction Buffers the IC from being overwhelmed RES 206-PPT Levels of the Incident Management System The public information officer Provides the media with a direct point of contact Provides frequent updates to the media RES 206-PPT Levels of the Incident Management System The tactical level The operations officer Actually runs the incident Is responsible for overall coordination of the rescue Implements tactical decisions Is responsible for all groups providing direct emergency support RES 206-PPT

19 Levels of the Incident Management System The logistics officer is responsible for Procuring equipment Procuring personnel RES 206-PPT Levels of the Incident Management System The task level The medical officer Reports to the operations officer Is responsible for establishing a medical control area Is responsible for establishing a transportation section Is responsible for the rehabilitation section RES 206-PPT Levels of the Incident Management System The extrication officer is responsible for The actual extrication of the victim All activities required to facilitate the rescue The pre-entry briefing RES 206-PPT

20 Levels of the Incident Management System Emergency support functions The air supply operations team Oversees pneumatic air shores and air bags Ensures proper operation of equipment Secures air supply RES 206-PPT Levels of the Incident Management System The cutting team Is responsible for all cutting and manufacturing of wood systems Must have members who are competent with saws Operates at a cutting station RES 206-PPT Levels of the Incident Management System The panel team Sets up, carries, and installs all shields or panels Must have at least four hard workers May be reassigned after the panels are set RES 206-PPT

21 Levels of the Incident Management System The shoring team Assembles and installs all shores and walers of the protective system Has members who Have manual dexterity Are efficient with hand tools RES 206-PPT Levels of the Incident Management System The rigging team Establishes lifting systems Must have systems ready to use RES 206-PPT Levels of the Incident Management System The heavy equipment operator Must have experience and talent May be needed to create a slope or a bench system Must position carefully so as not to cause a secondary collapse Must understand hand or communication signals RES 206-PPT

22 Levels of the Incident Management System The rapid intervention team/crew members Must be ready before stabilization activity Must be equipped for medical emergencies and secondary collapses May be rotated to gain experience in the actual rescue RES 206-PPT Logistics Support Functions Logistics Support Functions Are responsible for equipment storage and dissemination Use a predetermined location Employ a staging officer RES 206-PPT Student Performance Objective Given information from discussion, handouts, and reading materials, describe trench rescue operations. The student will perform to a written test accuracy of at least 70% and successfully complete the skills on a skills check-off sheet. RES 206-PPT

23 Review Technical Rescue Disciplines The Big Three The Specialized Training Cycle Service Levels Additional Requirements for Certification Levels The Risk-Benefit Analysis RES 206-PPT Review The FAILURE Acronym Types of Service Levels The Team Getting Your Equipment to the Scene OSHA Subpart P Excavations, 29 C.F.R The General Requirements of Trench Rescue RES 206-PPT Review OSHA and Trench Rescue Trench Collapse Emergencies The Trench Incident Management System Levels of the Incident Management System Logistics Support Functions RES 206-PPT

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25 Trench Rescue Operations Lesson 2-1 Soil Assessment and Types of Trench Collapse Student Performance Objective Given information from discussion, handouts, and reading materials, describe soil physics and conditions that lead to collapse. The student will perform to a written test accuracy of at least 70% and successfully complete the skills on a skills check-off sheet. RES 206-PPT Overview Soil Physics Non-entry Rescue Scenario Physical Forces Associated with Collapse Conditions and Factors that Lead to Collapse RES 206-PPT

26 Spoil Pile Slide Slough Failure Rotational Failure Shear Wall Collapse Toe Failure Bell Pier Condition Wedge Failure Overview RES 206-PPT Overview The Importance of Soil Classification Types of Soil Soil Testing Procedures RES 206-PPT Soil Physics Gravity is the force that draws everything to the center of the earth Hydrostatic pressure is the increased pressure caused by the addition of water to the soil profile Dry soil weighs between 60 and 80 lbs per cubic foot Water-saturated soil may weigh up to 150 lbs per cubic foot RES 206-PPT

27 Soil Physics Unconfined compressive strength (UCS) is the amount of resistance the soil has to pressure A higher UCS reflects a more cohesive soil A lower UCS reflects a less cohesive soil RES 206-PPT Soil Physics Active soil has a tendency to move due to The failure or removal of a protective system The inability of the soil to hold its own weight Passive soil does not have a tendency to move RES 206-PPT Non-Entry Rescue Scenario A worker has fallen from a ladder and broken his leg A spoil pile is next to the trench The trench walls are of concern The collapse potential is very high The victim is offered a ladder and a rope The victim climbs the ladder while tied to the rope The trench wall collapses after the victim is out No rescuers were injured while performing this rescue RES 206-PPT

28 Physical Forces Associated with Collapse Weights A cubic foot of soil weighs between 85 and 150 lbs with an average weight of 100 lbs A cubic foot of water weighs 62.4 lbs A cubic foot of rock weighs lbs A cubic foot of 1 / 2 rock and 1 / 2 air mix weighs about lbs per cubic foot A cubic foot of 1 / 2 rock and 1 / 2 water mix weighs about lbs per cubic foot RES 206-PPT Physical Forces Associated with Collapse Forces Vertical pressure Represents forces that may compress a victim Causes wall failure when tension overcomes cohesion RES 206-PPT Physical Forces Associated with Collapse Lateral pressure Is about 33% of the vertical pressure at a given depth Is 132 pounds per square foot at four feet deep Is distributed at about a 45º angle from the bottom of any given plane Is responsible for rotational failure RES 206-PPT

29 Physical Forces Associated with Collapse Rotational failure Is the most prevalent type of collapse Is caused by lateral pressure Is most dangerous 1 / 4 of the depth up from the bottom of the trench RES 206-PPT Physical Forces Associated with Collapse Shoring pressure Acts to transmit pressures from one side of the trench to the other Acts to equalize pressures May be overcome by lateral pressure, causing A collapse Shoring failure RES 206-PPT Conditions and Factors that Lead to Collapse The addition of water Adds weight to the soil Presents an absorption rate issue Causes a loss of strength of the soil Initially the soil may gain strength When saturated the soil will lose strength RES 206-PPT

30 Conditions and Factors that Lead to Collapse The freestanding time allows Environmental issues to become an concern Compressive forces to cause failure Time for nature to attempt to fill the trench back in RES 206-PPT Conditions and Factors that Lead to Collapse The varying soil profiles Cause problems determining the classification of the soil Cause problems determining the soil s potential for collapse Have different soil coefficients Sand may be layered between clay There may be a slip potential RES 206-PPT Conditions and Factors that Lead to Collapse Water may Provide a slip fault Be running water Underground streams Aquifers Be released from saturated soil RES 206-PPT

31 Conditions and Factors that Lead to Collapse The water table may Dictate the rescue situation Be just below the surface Be quite deep RES 206-PPT Conditions and Factors that Lead to Collapse The previously disturbed soil may be easy to spot because it may contain bottles, bricks, manmade objects, landfill, etc. The soil may be difficult to interpret because it lacks cohesiveness RES 206-PPT Conditions and Factors that Lead to Collapse The location of heavy equipment may cause pressure on unprotected trench walls The placement of emergency equipment should be kept back 300 feet and should not add to surface weight or scene vibration RES 206-PPT

32 Conditions and Factors that Lead to Collapse The spoil pile may Be less than two feet from the lip Cause multiple problems Vertical and lateral pressure due to weight Active soil sliding down the trench wall A restricted work area RES 206-PPT Conditions and Factors that Lead to Collapse Vibration From road traffic From machinery RES 206-PPT Spoil Pile Slide Spoil pile slide due to overburden pressure Spoil pile slide due to the angle of repose The angle is too steep The soil has dried, becoming less cohesive The soil is active RES 206-PPT

33 Spoil Pile Slide RES 206-PPT Slough Failure Is a loss of part of the trench wall Is a type of rotational failure May have a scoop-shaped appearance May be a result of unconfined hydrostatic pressure RES 206-PPT Slough Failure RES 206-PPT

34 Slough Failure May be due to the spoil pile being too close to the trench lip, causing vertical and lateral pressure May be indicated by cracks in and around the surface May be indicated by multiple soil layers May occur suddenly and without warning RES 206-PPT Rotational Failure May have a half-moon shape that starts back from the trench lip May result in large sections of trench wall falling May appear to have been dug by a spoon May create a very difficult problem to overcome with a rescue system RES 206-PPT Shear Wall Collapse Occurs when a section of the wall loses its ability to stand Usually happens across a vertical plane May be caused by cracks in the surface Water may wash out dirt Washing and drying create deeper cracks Is normally associated with cohesive soils May cause a larger collapse RES 206-PPT

35 Shear Wall Collapse RES 206-PPT Toe Failure Is a slough that occurs at the bottom of the trench Is characteristic of a cantilever May be caused by a sand pocket RES 206-PPT Toe Failure May be caused by the effects of water at the bottom of the trench May not be detected if a rescuer is standing above it Is hard to correct until a protective system is in place RES 206-PPT

36 Toe Failure RES 206-PPT Bell Pier Condition Is a toe failure on both sides of the trench Is the result of water conditions Is usually a slow process RES 206-PPT Bell Pier Condition RES 206-PPT

37 Wedge Failure Occurs in intersecting trenches Is characterized by an angle section of the trench wall falling from the corner of two intersecting trenches Can be sudden Can be catastrophic RES 206-PPT Wedge Failure RES 206-PPT The Importance of Soil Classification Soil classification Determines the performance of a soil Is based on a decreasing order of stability Is conducted in each of the layers of soil Is determined by the least stable soil Is used to determine the protective system RES 206-PPT

38 The Importance of Soil Classification Soil classification must be based on two tests A visual test A manual test RES 206-PPT Types of Soil Stable rock Is the least dangerous Is a natural solid material that can remain standing after excavation May fall on a worker after being excavated and set in a loose pile May present with other emergencies Falls Equipment failure RES 206-PPT Types of Soil Type A soils Are cohesive materials with an unconfined compressive strength of 1.5 tons per square foot or greater RES 206-PPT

39 Types of Soil Type A soils include Clay Silty clay Clay loam Sandy clay loam Cemented soils RES 206-PPT Types of Soil Type A soils are not classified as type A if they have any of the following conditions The soil is fissured The soil is subject to vibration The soil has been previously disturbed The soil is part of a sloped soil layer that is steeper than 4 horizontal to 1 vertical The material is subject to other factors that would require it to be classified as a less stable material RES 206-PPT Types of Soil RES 206-PPT

40 Types of Soil Type B soils May be cohesive materials with an unconfined compressive strength greater than 0.5 tsf but less than 1.5 tsf RES 206-PPT Types of Soil Type B soils may be granular cohesionless material Angular gravel Silt Silt loam Sandy loam Sandy clay loam RES 206-PPT Types of Soil Type B soils May be previously disturbed soil May be downgraded type A soil RES 206-PPT

41 Types of Soil Type C soils Are cohesive materials with an unconfined compressive strength of 0.5 tsf or less RES 206-PPT Types of Soil Type C soils include Granular soils Sand Soils from which water is freely flowing Submerged rock that is not stable Sloped or layered systems where the layers dip into the excavation at a slope of 4 horizontal to 1 vertical or steeper RES 206-PPT Types of Soil C-60 soil Was designated by Speed Shore Is a moist cohesive soil or a dense granular soil that does not fit into type A or type B classifications May be cut near vertically and will stand long enough to allow shoring to be properly installed Is permitted because OSHA allows for other classification tables RES 206-PPT

42 Soil Testing Procedures The visual test Visually inspect Excavated material Soil from the trench wall The excavation site in general RES 206-PPT Soil Testing Procedures Look for the following Layers that change with depth The weakest soil Soil that has been previously disturbed The soil make up The presence of utilities, mixed soil, similar particles of soil, fissures, spalling, cracks, hydrostatic forces RES 206-PPT Soil Testing Procedures The manual test is used to Determine soil characteristics Learn relative strength under force Formulate the material s ability to free stand RES 206-PPT

43 Soil Testing Procedures The plasticity test Is used to see if the soil may be deformed or molded without a change in total volume Is done by molding a wet or moist sample into a ball and then attempting to roll it into a thread 1 8 of an inch in diameter and two inches long Is used to consider a soil s cohesiveness if the threads do not crumble or if a two-inch thread can be held at one end without tearing RES 206-PPT Soil Testing Procedures The dry strength test The dry strength test is performed to determine the propensity of the soil to fissure If the soil is dry and crumbles on its own into individual grains or fine powder it is granular RES 206-PPT Soil Testing Procedures The dry-strength test (continued) If the soil is dry and falls into clumps and then smaller clumps that are difficult to break down, then it may contain Clay and gravel Clay and sand Clay and silt If the dry soil breaks into clumps that do not break into smaller clumps without difficulty, it may be considered unfissured RES 206-PPT

44 Soil Testing Procedures The thumb penetration test Is used to estimate the unconfined compressive strength of cohesive soils Is performed by extending a thumb against an exposed sample and attempting to push through it Indicates type A soil By a ready indention By a difficult penetration RES 206-PPT Soil Testing Procedures RES 206-PPT Soil Testing Procedures The thumb penetration test indicates type C soil By easy penetration of several inches by the thumb By molding the soil with little effort The thumb penetration test should be done as soon as possible after excavation to prevent the environment from affecting the sample RES 206-PPT

45 Soil Testing Procedures The drying test Is used to determine the difference between cohesive material with fissures, unfissured cohesive material, and granular material Is performed by drying a sample of soil that is 6 inches long and 1 inch thick Fissured material behavior Unfissured cohesive material behavior Granular material behavior RES 206-PPT Soil Testing Procedures Penetrometer and shear vane tests Are performed by field instruments that may be used to determine unconfined compressive strength Are performed by applying force into the trench wall Work accurately when the soil has some moisture content Are read numerically RES 206-PPT Soil Testing Procedures RES 206-PPT

46 Soil Testing Procedures Laboratory testing Is not practical on scene Is complicated but accurate Helps develop mathematical determinations Uses samples from varying depths obtained with an auger RES 206-PPT Student Performance Objective Given information from discussion, handouts, and reading materials, describe soil physics and conditions that lead to collapse. The student will perform to a written test accuracy of at least 70% and successfully complete the skills on a skills check-off sheet. RES 206-PPT Review Soil Physics Non-entry Rescue Scenario Physical Forces Associated with Collapse Conditions and Factors that Lead to Collapse RES 206-PPT

47 Spoil Pile Slide Slough Failure Rotational Failure Shear Wall Collapse Toe Failure Bell Pier Condition Wedge Failure Review RES 206-PPT Review The Importance of Soil Classification Types of Soil Soil Testing Procedures RES 206-PPT

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49 Trench Rescue Operations Lesson 2-2 Trench Rescue Equipment/ Trench Rescue Assessment Student Performance Objective Given information from discussion, handouts, and reading materials, describe trench rescue equipment and trench rescue assessment. The student will perform to a written test accuracy of at least 70% and successfully complete the skills on a skills check-off sheet. RES 206-PPT Overview Personal Protective Equipment Development of a Safe Culture Equipment for Trench Rescue Operations Calculating the Weight of an Object Gravity Movement Mechanics RES 206-PPT

50 Overview Air Bags for Trench Rescue Cribbing Wedges Time of Alarm Arrival at the Scene Assessment During the Emergency RES 206-PPT Personal Protective Equipment Standard issue equipment Should minimize the effects of weather Should minimize trauma around machinery and tools Includes a jumpsuit or long-sleeve shirt and pant combination, gloves, steel-toed boots, helmet, eye protection, hearing protection, safety vest RES 206-PPT Personal Protective Equipment Clothing Turnout gear Jumpsuits Long-sleeved shirt and pant RES 206-PPT

51 Personal Protective Equipment Gloves Firefighting gloves Standard leather garden gloves Vehicle extrication gloves Nomex flight gloves RES 206-PPT Personal Protective Equipment Head protection A firefighting helmet A heavy-duty construction helmet RES 206-PPT Personal Protective Equipment Eye protection Helmet mounted protection (not recommended) Full-face goggles Standard safety glasses RES 206-PPT

52 Personal Protective Equipment Foot protection Steel toed Steel shanked A high top boot RES 206-PPT Personal Protective Equipment Specialty items Respiratory Protection Dust mask Self-contained breathing apparatus Supplied air breathing apparatus RES 206-PPT Personal Protective Equipment Hearing protection Blocks out high frequencies Allows for communication RES 206-PPT

53 Personal Protective Equipment Skullcaps Are worn under the helmet Allow for the cooling action of sweat Are cooled with water RES 206-PPT Personal Protective Equipment Leather chaps Should be used in the cutting area Might prevent or deflect a chain saw injury RES 206-PPT Development of a Safe Culture Does not happen over night Requires hours of training and discipline RES 206-PPT

54 Equipment for Trench Rescue Operations Ground pads Distribute weight over a greater area Help to prevent secondary collapse Come in different types 4 8 ½ sheets of plywood or pieces of lumber RES 206-PPT Equipment for Trench Rescue Operations Types of Sheeting Interconnected steel uprights Sheets of plywood/timber Manufactured panels Homemade panels ShorForm FinForm Plywood RES 206-PPT Equipment for Trench Rescue Operations RES 206-PPT

55 Equipment for Trench Rescue Operations Facilitating ease of use and storage of sheeting Cut off the corners of the sheeting at a 45 angle Drill hand holds or holes for ropes Use strongbacks RES 206-PPT Equipment for Trench Rescue Operations RES 206-PPT Equipment for Trench Rescue Operations Placement Tie a rope through the panel holes and lower the panel vertically Form a loop through which the strongback can be vertically lowered RES 206-PPT

56 Equipment for Trench Rescue Operations Timber shores Are made in many dimensions Are made from Douglas Fir Must have a bending strength of not less than 1500 pounds per square inch Must not exceed 20 feet in width Are relatively low in cost Can be cut to varying lengths Are selected by a process RES 206-PPT Equipment for Trench Rescue Operations Screw jacks Have a boot end which fits over a piece of wood Are tightened by a thread and yoke assembly Are relatively inexpensive Are not as strong as other shores Must not be overextended RES 206-PPT Equipment for Trench Rescue Operations Hydraulic shores May have the shore and uprights as one unit Are lowered into the trench and set entirely from above Are expanded using a five-gallon reservoir of fluid Are shut off from fluid and pump after expansion Do not work well if the walls of the trench are not vertical or near vertical RES 206-PPT

57 Equipment for Trench Rescue Operations Pneumatic air shores Come in a variety of lengths Are made from lightweight tubular aluminum Are quick, strong, and dependable Have a multitude of extensions and attachments Are extended by using compressed air Have a few disadvantages RES 206-PPT Equipment for Trench Rescue Operations Tools and appliances Shovel Entrenching tool Hammer Duplex nails Chain saw Electric powered ventilation equipment Ladders Dewatering devices RES 206-PPT Calculating the Weight of an Object Multiply the width by the depth by the length = 160 cubic feet Multiply the cubic feet by the weight per cubic pound = 24,000 pounds RES 206-PPT

58 Gravity Gravitational terms Gravity The tendency of an object to be attracted to another object in direct proportion to its mass Lifting the action necessary to move anything Lowering controlling the descent of an object RES 206-PPT Gravity Moving exerting enough force on an object to move it Stabilizing keeping the object from moving by applying a counterforce Friction a measure of the amount of force it takes to move an object across the surface of another object RES 206-PPT Gravity Center of Gravity The point on a body around which the body s mass is evenly distributed The point on a body where all forces of the earth s gravitational pull are equal The junction of the horizontal, vertical, and diagonal axes of an object The absolute center of an object RES 206-PPT

59 Movement Moment of force Is mass multiplied by the distance away from the turning point or fulcrum Is the amount of force rotating around the fulcrum times the distance from the fulcrum RES 206-PPT Movement The teeter-totter The balance can be determined by multiplying the bigger child s weight by the distance he is from the fulcrum (100 lbs 4 feet equals 400 lbs) The smaller child s weight is divided into the 400 lbs to determine the distance he should sit from the fulcrum (400 lbs divided by 50 lbs equals 8 feet) RES 206-PPT Mechanics The Theory of Mechanics Energy Is the capacity for doing work and overcoming resistance Is how hard it is to push or pull something a distance Is measured in feet/pounds, either in kinetic or potential energy Is what it takes to accomplish work RES 206-PPT

60 Mechanics Work Is the distance times force or force as it is applied to set it in motion Is explained by the climbing of a mountain the climbing is the work RES 206-PPT Mechanics Application of Mechanics The creation of a positive output in a given situation (mechanical advantage) The ratio of the output of force a machine exerts compared with the input force furnished to that machine to do the work RES 206-PPT Mechanics Types of Machines Class 1 lever Has the fulcrum placed between the force and the load Has a calculated mechanical advantage RES 206-PPT

61 Mechanics RES 206-PPT Mechanics Class 2 lever Is most effective when moving objects on a horizontal plane Has the load between the force and the fulcrum RES 206-PPT Mechanics RES 206-PPT

62 Mechanics Class 3 lever Is the hardest to understand Has the force located between the load and the fulcrum RES 206-PPT Mechanics RES 206-PPT Mechanics Inclined planes Are a form of simple machine Work by reducing the required force over time May be ladders in the trench rescue environment RES 206-PPT

63 Mechanics RES 206-PPT Air Bags for Trench Rescue Low pressure bags use 7 psi Limited lift capacity Higher lift ability in height Medium pressure bags use 22 psi High pressure bags use 80 to 120 psi Lift a greater amount of weight Are unable to lift as high as a low pressure bag RES 206-PPT Air Bags for Trench Rescue How air bags work Air bags must have an air source Air bags must have a regulator The effectiveness of air bags is limited by the compressibility of air and the inside surface area of the bag The lifting capacity of air bags is limited by the amount of bag surface area that can contact the object RES 206-PPT

64 Air Bags for Trench Rescue Using air bags Determine the lift Multiply the length of the bag times the width by the recommended operation pressure to obtain maximum lift capacity Determine the weight of the object to be lifted and the surface area of the lift point Calculate the lift capacity based on the contact surface area RES 206-PPT Air Bags for Trench Rescue Using air bags (continued) Determine if a greater surface area is needed Determine if the lift is possible with the available equipment RES 206-PPT Air Bags for Trench Rescue RES 206-PPT

65 Air Bags for Trench Rescue High pressure air bags Design Rubber or neoprene material Steel bands or Kevlar A coarse surface A working capability of 80 to 120 psi RES 206-PPT Air Bags for Trench Rescue Drawbacks of high-pressure air bags Do not lift very high May need to be stacked only up to two Always put the larger bag on the bottom The lift capacity is that of the smaller bag RES 206-PPT Air Bags for Trench Rescue Durability of high-pressure air bags Very durable Not field repairable RES 206-PPT

66 Air Bags for Trench Rescue Low-pressure air bags Are flexible rubber bags Are used to fill voids in trench walls Are used to lift some objects Operate at 7 to 12 psi Will lift an object higher than a high-pressure bag RES 206-PPT Air Bags for Trench Rescue Low-pressure air bags Will not lift the weight of a high-pressure bag Are field repairable Require a lot of air to accomplish a lift May be used outside of the trench to lift RES 206-PPT Air Bags for Trench Rescue RES 206-PPT

67 Cribbing May become brittle when natural moisture content is lost Is required for anything being lifted in a rescue Should be no more than an inch from the item being lifted RES 206-PPT Cribbing May be made from construction grade lumber RES 206-PPT Cribbing RES 206-PPT

68 Cribbing May be cut in varying lengths May be used in a cribbing system 4-point crib system 9-point crib system Full-box crib system RES 206-PPT Cribbing Will support varying amounts of weight 4 4 cribbing will support 6,000 lbs per contact point 6 6 cribbing will support 15,000 lbs per contact point RES 206-PPT Cribbing RES 206-PPT

69 Cribbing Is dependent on the quality of the ground Is used by stacking timbers in alternating rows to build systems The rows should have a slight overhang to the previous row The height should be no more than three times the diameter of the base RES 206-PPT Wedges Are cut pieces of lumber that form an inclined plane Are used to fill voids of varying sizes Are used until a full piece of lumber will fit in the cribbing system RES 206-PPT Wedges RES 206-PPT

70 Wedges Are used to tighten objects Are used to take up space between wales and uprights Are used to tighten shores to uprights RES 206-PPT Time of Alarm What happened? Why was the excavation work being done? Is the victim completely buried? Is the situation a trench collapse or some other form of injury in the trench? Will I have access problems? How is the weather? RES 206-PPT Arrival at the Scene Who is in charge and what happened? Is there a language barrier? Is the collapse within your scope of operations? What are the injuries? What is the victim s survivability profile? RES 206-PPT

71 Arrival at the Scene What type of protective system is/was in place? Do I have the resources to accomplish this mission successfully? Do I have a solid rescue plan? Have I given a preincident briefing to rescue personnel? Can I mitigate this rescue with a rapid non-entry rescue technique? RES 206-PPT Assessment During the Emergency Evaluate constantly Anticipate problems Consider the following when looking for buried victims The victim may be at the end of a pipe string A flagstick may indicate trench depth RES 206-PPT Assessment During the Emergency Consider the following when looking for buried victims (continued) Laser target may provide helpful information A competent person may know the location the victim was last seen Tapping sounds may be heard when listening in the pipes for signs of life Determining what the victim was doing at the time of the incident may help determine his location RES 206-PPT

72 Assessment During the Emergency Consider the following when looking for buried victims (continued) Exposed limbs may not be in normal orientation A cell phone call to the victim may help in locating him Listening devices may be used to help locate the victim RES 206-PPT Assessment During the Emergency Develop a rescue plan for the incident Hold a pre-entry briefing Involve all members Brief on safety matters Brief on tactics and strategies RES 206-PPT Assessment During the Emergency The pre-entry briefing (continued) Identify all known hazards Explain emergency signals Identify the command structure Explain radio frequencies Explain tactical objectives RES 206-PPT

73 Student Performance Objective Given information from discussion, handouts, and reading materials, describe trench rescue equipment and trench rescue assessment. The student will perform to a written test accuracy of at least 70% and successfully complete the skills on a skills check-off sheet. RES 206-PPT Review Personal Protective Equipment Development of a Safe Culture Equipment for Trench Rescue Operations Calculating the Weight of an Object Gravity Movement Mechanics RES 206-PPT Review Air Bags for Trench Rescue Cribbing Wedges Time of Alarm Arrival at the Scene Assessment During the Emergency RES 206-PPT

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75 Trench Rescue Operations Lesson 3-1 Hazard Control and Victim Considerations Student Performance Objective Given information from discussion, handouts, and reading materials, describe hazard control and victim considerations. The student will perform to a written test accuracy of at least 70% and successfully complete the skills on a skills check-off sheet. RES 206-PPT Overview Hazard Categories Hazard Control Phases Atmospheric Monitoring for Trench Rescue Action Guidelines Specific Monitoring Measurements Standard Operating Guidelines Hazard Control Using Ventilation Atmospheric Monitoring Concepts RES 206-PPT

76 Overview Non-Entry Rescue and Victim Self-Rescue Pre-entry Briefing Gaining Access to Your Victim Patient Care Considerations Termination and Post-Incident Considerations RES 206-PPT Overview Ground Pads Sheeting Shoring Isolation Tunnels, Shafts, and Engineered Systems Commercial Techniques RES 206-PPT Hazard Categories Mechanical hazards Mechanical hazards may involved machines or other entrapping mechanisms Everything must be brought to zero mechanical state Removing the keys Locking out electrical devices Removing machines from the collapse zone RES 206-PPT

77 Hazard Categories Chemical hazards May have been unearthed during digging operations May have been carried into the trench by a worker RES 206-PPT Hazard Categories RES 206-PPT Hazard Categories Manmade hazards Are usually the reason for the collapse Are part of the normal work that takes place May be the spoil pile and equipment location RES 206-PPT

78 Hazard Categories Electrical hazards Should be controlled by a professional Come in many forms Power lines Telephone lines Should be clearly marked by a utility location service RES 206-PPT Hazard Categories Water hazards (from groundwater or rain) Build a cover for the trench Divert rain Dewater Deploy an inflatable tent to cover trench RES 206-PPT Hazard markings Red Orange Yellow Green Blue Violet Pink White Hazard Categories RES 206-PPT

79 Hazard Control Phases Follow a logical order Address the greatest hazard first Address hazards that are not readily apparent Use standard nomenclature Hazmat Hot Warm Cold RES 206-PPT RES 206-PPT Hazard Control Phases Perform the following activities in the general area Staging Cutting Logistical support Rehab Vehicle parking RES 206-PPT

80 Hazard Control Phases Perform the following activities in the rescue area Air supply Panel team Shoring personnel Safety officer RES 206-PPT Atmospheric Monitoring for Trench Rescue Atmospheric monitoring in confined spaces is required by OSHA Confined spaces have features that are similar to the features of a trench Atmospheric monitoring should be performed by trained personnel Hazmat personnel Support function personnel RES 206-PPT Atmospheric Monitoring for Trench Rescue Monitor the atmosphere to Detect the presence of an IDLH atmosphere Gauge the ventilation of the trench RES 206-PPT

81 Atmospheric Monitoring for Trench Rescue RES 206-PPT Atmospheric Monitoring for Trench Rescue Consider the following when monitoring: What is the nature of the hazard that I am monitoring? Are there sources of electrical interference around? What are the environmental site conditions that you are operating in? Are there gases and vapors interfering with your monitor? RES 206-PPT Action Guidelines Guidelines outlined in OSHA Indicate that you should take specific actions when monitor readings reach certain levels Are based on preset alarms on your monitors that will alert when a certain level, parameter, or product is detected RES 206-PPT

82 Action Guidelines General monitoring guidelines Rule 1 Monitor in order Oxygen Flammability/combustibility Toxicity RES 206-PPT Action Guidelines Rule 2 Always monitor at multiple levels in the trench Mixtures of gases may accumulate at different levels depending on their vapor density Different products have different vapor densities Methane is lighter than air and may leave the trench Carbon monoxide is about the same density as air and will diversify with the air Hydrogen sulfide is heavier than air and will settle on the bottom of the trench RES 206-PPT Action Guidelines Rule 3 Know your monitor s limitations Rule 4 Understand the relationship between flammability and toxicity Rule 5 A substance that comes after you is much more dangerous than one that expects you to come to it Rule 6 Know your monitor s operational parameters RES 206-PPT

83 Action Guidelines Rule 7 Check batteries every shift Rule 8 Zero and field calibrate your instrument in clean air Oxygen level should read 20.9% Flammability should read 0% of LEL Toxicity should read 0 PPM RES 206-PPT Action Guidelines Rule 9 Sample from upwind Rule 10 Always assign a competent person to perform atmospheric monitoring RES 206-PPT Specific Monitoring Measurements Oxygen Is measured at between 0 and 25% Is considered deficient at levels of 19.5% or below and will cause an alarm Is considered rich at or above levels of 23.5% and will cause an alarm Is considered a normal concentration at 20.9% RES 206-PPT

84 Specific Monitoring Measurements Flammable and combustible readings Combustible gas indicators (CGIs) determine the presence of flammable vapors of hydrocarbon products Monitors are calibrated for certain flammable gases Tests for flammability should be conducted when it is suspected that the trench is contaminated, to detect leaks, or when investigating any unknown material Any concentration at 10% of the LEL will sound an alarm RES 206-PPT Specific Monitoring Measurements Toxicity Toxicity is measured in parts per million Monitors have one or two toxic sensors Alarm settings are set at 35 ppm for carbon monoxide 10 ppm for hydrogen sulfide Time-weighted averages for an OSHA 8- hour exposure RES 206-PPT Standard Operating Guidelines Monitoring should be done Before entry Every five minutes RES 206-PPT

85 Standard Operating Guidelines RES 206-PPT Standard Operating Guidelines Monitoring should follow guidelines Collect and record monitor readings throughout the entry and rescue/ recovery operation Capture readings on the trench rescue tactical worksheet Report readings to the extrication officer or the operations officer on a continual basis RES 206-PPT Standard Operating Guidelines Monitoring (continued) Report any fluctuations or changes in readings immediately Report any alarm levels immediately and take action Never leave the monitor unattended Always use the hazmat team to your advantage RES 206-PPT

86 Hazard Control Using Ventilation Ventilation Is the first method of choice in trench emergencies because it is fast and easily monitored Does not work in every situation Is only as good as the technique used RES 206-PPT Hazard Control Using Ventilation Ventilation (continued) Will not help if there is an off-gassing product in the trench Is dependent upon weather and environmental factors May require multiple fans RES 206-PPT Atmospheric Monitoring Concepts Atmospheric Monitoring: Read the instruction manual for your device Practice, practice, practice Use the most competent person for the job RES 206-PPT

87 Non-Entry Rescue and Victim Self-Rescue Are the preferred methods for trench rescue Reduce risk to rescue personnel Should be considered in every incident May be accomplished by Providing a ladder for victims to climb out on their own Supplying a harness or wristlets and lifting victims out of the trench May require victims to dig themselves out RES 206-PPT The Pre-Entry Briefing Is based on a risk-benefit analysis Is the time when all rescue personnel hear the rescue plan Allows the IC to think out loud Allows rescuers to openly question the plan RES 206-PPT The Pre-Entry Briefing Must contain the basics of the rescue The overall goal of the operation Position assignments Protective system design Safety requirements Accountability system Emergency procedures RES 206-PPT

88 Gaining Access to Your Victim Gaining access to your victim Is based on the type of emergency May be difficult due to substandard protective systems already in place RES 206-PPT Gaining Access to Your Victim Tons of dirt may have to be removed by using Hands and buckets Centrifugal vacuum trucks Positive displacement vacuum trucks Hydro Vac trucks Rescue Vac systems RES 206-PPT Gaining Access to Your Victim When using vacuum systems, soil reduction will likely have to be done. Air knives are frequently used to break the soil into smaller particles. RES 206-PPT