TRENCH RESCUE No need to click to advance, the show will automatically advance.

INTRODUCTION Each year, 1,100 workers are seriously injured and approximately 100 workers die in trenching and excavating related accidents.

TRENCH CRITERIA A trench is deeper than it is wide, but no more than 15’ wide at the bottom A trench is deeper than it is wide, but no more than 15’ wide at the bottom Trenches over 4’ requires shoring Trenches over 4’ requires shoring Spoil pile should be a minimum of 2’ from edge. Spoil pile should be a minimum of 2’ from edge.

INITIAL RESPONSE One Medic Unit One Truck Company One Rescue Squad/Extrication Unit LFRD Duty Officer DFRS Battalion Chief EMS Duty Officer Montgomery County Police - Emergency Response Urban Search & Rescue Team Utilities, as appropriate

SPOTTING THE APPARATUS Proximity to the trench - not closer than 250 ft. Proximity to the trench - not closer than 250 ft. Accessibility for other rescue vehicles - at least 100 ft. from trench Accessibility for other rescue vehicles - at least 100 ft. from trench

FIRST ARRIVING FIRST ARRIVING UNIT MUST: Restrict entry to site Establish initial command Position unit no closer than 250 feet Establish off-site staging for other responding apparatus Eliminate sources of vibration, stop and shut down construction equipment, stop traffic.

SIZE-UP Establish ICS Establish ICS Determine the Civilian in charge Determine the Civilian in charge Are there any witnesses ? Are there any witnesses ? Now find out the facts Now find out the facts Identify any communication barriers Identify any communication barriers

Identify hazards Identify hazards –Downed electrical wires –Leaking natural gas lines –Broken water or sewer lines –Traffic movement causing vibration –Crowd control

OUTER CIRCLE CHECK Identify witnesses to incident. Identify job foreman. Begin to establish incident perimeter, 100 feet minimum.

INNER CIRCLE CHECK Approach site from end of trench. Identify victim location using witnesses. Identify number of patients. Establish patient condition if possible. DO NOT ENTER TRENCH

How is the patient trapped? Totally buried, if so how deep Trapped by utilities Where ? Don’t forget to consider the victim’s SURVIVAL PROFILE Direct non entrapped personnel out of the trench. Establish full command structure.

0 feet 500 Feet 250 feet 100 feet Rehab USAR Units IC Personnel Staging PIO Rescue Hot Zone Hot Zone 100 feet Warm Zone Warm Zone 250 feet Cold Zone Cold Zone 500 feet COMPLETE PHYSICAL PERIMETER Trench Staging

VICTIMS SURVIVAL PROFILE Time is the biggest factor Time is the biggest factor 8-10 min. to respond 8-10 min. to respond 10 min to set up 10 min to set up 18 in = lbs 18 in = lbs Most trenches fail less than 12 ft. deep and 6 ft. wide Most trenches fail less than 12 ft. deep and 6 ft. wide

SOIL EFFECTS IMPACT CRUSHES THE VICTIM: Breaking Limbs Breaking Limbs Causing Internal Injuries Cuts And Abrasions Cuts And Abrasions TRAUMATIC ASPHYXIATION: Soil Restricts Expansion Of The Victims Chest Blocks Airways Causing Suffocation

TRENCH 15 ft. deep or over 6 ft. wide 15 ft. deep or over 6 ft. wide

TYPES OF TRENCH ACCIDENTS Spoil Pile Slide Spoil Pile Slide UNSAFE SPOIL PILE Spoil Pile Slide: -occurs when improper techniques are used and the excavated material NOT PLACED is NOT PLACED far enough away from the edge of the excavation

Slough Trench Lip Slough Trench Lip Slough - In Slough - In Slough In (Cave in): -most commonly occurs to previously excavated material (primarily sand and gravel mixtures)

Side Wall Shear Side Wall Shear Side Wall Shear: -this commonly occurs in clay type soils that are exposed to drying.

WALL FAILURE [in order] 1. Disturbed soil 1. Disturbed soil 2. Intersecting trenches 2. Intersecting trenches 3. Narrow right-of-way 3. Narrow right-of-way 4. Vibrations 4. Vibrations 5. Seepage of surface water 5. Seepage of surface water 6. Drying of exposed walls 6. Drying of exposed walls 7. Inclined layers of soil 7. Inclined layers of soil

TYPES OF SOIL THAT WILL FAIL [in order] Clay and or mud Clay and or mud Sand Sand Wet dirt {probably silty clay} Wet dirt {probably silty clay} Sand, gravel, and clay mix Sand, gravel, and clay mix Rock Rock Gravel Gravel Sand and gravel Sand and gravel

SOIL TYPES Type A - Most stable: clay, silty clay, and hardpan (resists penetration). No soil is Type A if it is fissured, is subject to vibration of any type, has previously been disturbed, or has seeping water. Type B - Medium stability: silt, sandy loam, medium clay and unstable dry rock; previously disturbed soils unless otherwise classified as Type C; soils that meet the requirements of Type A soil but are fissured or subject to vibration. Type C - Least stable: gravel, loamy sand, soft clay, submerged soil or dense, heavy unstable rock, and soil from which water is freely seeping. Layered geological strata Layered geological strata (where soils are configured in layers) - The soil must be classified on the basis of the soil classification of the weakest soil layer. Each layer may be classified individually if a more stable layer lies below a less stable layer, i.e. where a Type C soil rests on top of stable rock. Layered geological strata

Terms used in Trench Rescue Angle of repose - the greatest angle above the horizontal plane at which loose soil will lie without sliding. Angle of repose - the greatest angle above the horizontal plane at which loose soil will lie without sliding. Back fill - the refilling of a trench, or the material use to refill a trench, or to fill a void between two surfaces. Back fill - the refilling of a trench, or the material use to refill a trench, or to fill a void between two surfaces.

Terms Back shoring - the shoring of a void as found after a slough in, or may be used in a “T” trench. Back shoring - the shoring of a void as found after a slough in, or may be used in a “T” trench. Cleats - temporary support for struts Cleats - temporary support for struts Kick out - accidental release or failure of shore or strut. Kick out - accidental release or failure of shore or strut. Spoil pile - the material excavated from the trench Spoil pile - the material excavated from the trench

Terms Sheeting - 1” plywood Sheeting - 1” plywood Struts - the horizontal bracing between the trench walls. Struts - the horizontal bracing between the trench walls. Uprights - the vertical supports, usually 2x8’s the depth of the trench. Uprights - the vertical supports, usually 2x8’s the depth of the trench. Wedges - matched sets used to hold timber struts in place. Wedges - matched sets used to hold timber struts in place.

REVIEW  Restrict Entry To Site  Establish Initial Command  Position Unit No Closer Than 250 Feet  Establish Off-site Staging For Other Responding Apparatus  Shut Apparatus and Equipment  Stop all Traffic within 250 ft. DO NOT ENTER TRENCH

Do NOT trade a life for a body!!!

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