TRENCH RESCUE

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

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

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

4. 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 INITIAL RESPONSE

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

6. 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.

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

8. SIZE-UP • Identify hazards • Downed electrical wires • Leaking natural gas lines • Broken water or sewer lines • Traffic movement causing vibration • Crowd control

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

10. 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

11. INNER CIRCLE CHECK • 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.

12. 0 feet COMPLETE PHYSICAL PERIMETER 500 Feet Staging • Hot Zone 100 feet • Warm Zone 250 feet • Cold Zone 500 feet Rehab 250 feet IC USAR Units Personnel Staging 100 feet Rescue PIO Trench

13. VICTIMS SURVIVAL PROFILE • Time is the biggest factor • 8-10 min. to respond • 10 min to set up • 18 in = 2500-3000 lbs • Most trenches fail less than 12 ft. deep and 6 ft. wide

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

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

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

17. Types of Trench Accidents • Slough Trench Lip • Slough - In Slough In (Cave in): -most commonly occurs to previously excavated material (primarily sand and gravel mixtures)

18. Types of Trench Accidents • Side Wall Shear Side Wall Shear: -this commonly occurs in clay type soils that are exposed to drying.

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

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

21. 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(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.

22. Terms used in Trench Rescue • 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.

23. Terms • 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 • Kick out - accidental release or failure of shore or strut. • Spoil pile - the material excavated from the trench

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

25. 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

26. Do NOT trade a life for a body!!!

27. Lets see what you remember Hit “Esc” to stop the show.