Hoffman Estates Fire Department Trench Rescue Guidelines PDF

HOFFMAN ESTATES FIRE DEPARTMENT STANDARD OPERATING GUIDELINES SOG Category & Identification Number: EFFECTIVE DATE: SPECIALIZED OPERATION - 009 January 1, 2022 NIMS COMPLIANT SOG T...

HOFFMAN ESTATES FIRE DEPARTMENT STANDARD OPERATING GUIDELINES SOG Category & Identification Number: EFFECTIVE DATE: SPECIALIZED OPERATION - 009 January 1, 2022 NIMS COMPLIANT SOG Title: Trench Rescue Guidelines Revision: 1 APPROVED BY: NUMBER OF PAGES: Re-evaluation Date: Alan Wax January 1, 2025 Fire Chief 8 PURPOSE Trench rescue operations present a significant danger to Fire Department personnel and may involve complex requirement for shoring, hand tools, earth-moving equipment and other specialized resources. The safe and effective management of these operations requires special considerations. POLICY All rescue operations must follow all IDOL and OSHA criteria for trench/ excavation operations. For the purpose of this policy, a trench shall be defined as any manmade cut, cavity, trench or depression in an earth surface, formed by earth removal which is greater than or equal to five (5) feet in depth (or with a potential for collapse), and the width is not greater than 15 feet (measured at the bottom). Cave-ins and collapses generally occur because of unstable soil conditions combined with improper or inadequate shoring. The potential for additional collapse must always be considered as a primary hazard and personnel must be aware that any action may disturb the temporary stability and cause an additional collapse. The temporary stability at any point in an operation may be disturbed by removing soil or debris, by adding weight near the edge of an open cut, by vibration (such as vehicle movement), rain, or simply by the passage of time. PROCEDURE A. LOCATING THE VICTIM Like water rescues, the last known position of the victim should be determined as best as possible. Trench rescue victims tend to be buried in one of two ways. In many cases victims are found "frozen" in the act of the job they were performing, in other cases, victims are "washed-away" from the area they were working in, much like being caught in a "dirt avalanche". You should seek as much information as you can from co-workers regarding victim's last known position. If the victim is only partially buried, attach a line to him as soon as possible so that he may 1  be relocated quickly in the event of another cave-in. If the victim is completely buried, consider marking the dirt with a powder extinguisher. B. GENERAL OBJECTIVES 1. RESCUE MODE. If Command determines that the buried victim has at least a good probability for survival, all operations are to be considered in the rescue mode. The gain must be worth the risk of the rescuer's safety. Once you have determined where the victim is most likely to be, have removed the hazards and protected the trench edges, the next step is to shore the area most likely to protect the victim from additional cave-ins. Once this is accomplished, the next step is to shore on either side of the first one to give rescue personnel an area to work in. As the rescue progresses, the shoring operation may have to be extended in one direction or the other to find and expose the victim. All shoring operations must follow IDOL criteria. If you dig more than 2½ feet below the bottom cross braces, you must add an additional cross brace. Remember, never work outside the last cross brace...this is the most dangerous part of the trench. 2. BODY RECOVERY MODE. If Command determines that the buried victim has a poor probability for survival, all operations are to be considered in the body recovery mode. In this mode, the trench is to be sloped whenever possible in order to access the body. All operations are to follow IDOL criteria. 3. PROTECTIVE CLOTHING Helmets and gloves should be worn by all rescue personnel in the trench area. Face shields or goggles should be in place when digging or nailing. Steel-toed bunker boots should be worn. 4. DIGGING a. RESCUE MODE. Digging should be done by hand with small tools. Cut- down hoes and shovels work well. When victim location is unknown, the dirt that is excavated should be removed completely from the trench to keep you from having to move it twice. Filling and raising five gallon buckets by rope works well. Digging should be vigorous, but gentle...the victim may be only a few inches down. Rotate personnel often so that the digging will continue at a fast pace. b. BODY RECOVERY MODE. Heavy machinery may be used in body recovery activities along hand digging. 5. MOVING SHORES 2  As a general rule, shoring should not be removed until all operations are completed, and OSHA has inspected the site. In extreme situations, however, where resources are limited, and you find a live victim at one end of your work area, it may become necessary to move one set of shores from one end of the work area to the other. If you need to remove one set of shores to continue in the other direction, you should remove all personnel from the trench except the individual performing the actual removal. Shores should be removed from bottom-up (except for hydraulic shores which are removed from top-down, from outside the trench). Always keep yourself no further than waist deep below the last good cross brace. Ropes should be used to remove the cross braces so that personnel are not put at risk. 6. TRENCH RESCUE GUIDELINES a. NEVER ENTER AN UNSHORED TRENCH. b. Park all necessary equipment at least 100' away. c. Park all unnecessary equipment at least 300' away. d. Stop all traffic within 300'. e. Keep all persons out of an unsafe trench...use police intervention if necessary. f. Try to get a good fix on the patient's last known position. g. Trench atmosphere must be monitored and vented, or airpacks must be worn if air quality is dangerous. h. Keep non-essential personnel away from the trench walls. i. Move spoil pile, and any other material at least two feet from trench. j. Protect edges of trench with plywood or planking. k. Do not allow the use of heavy machinery for digging within the trench during a rescue operation. l. Personnel working in trench should be in bunker boots. Helmets and gloves should also be worn. m. Finform sheeting (with 2"x 6" boards attached) must be used whenever airshores or hydraulic shores are used. Sheeting must extend 2" above the edge of the trench and must extend to the bottom of the trench. Solid sheeting is required with no gaps between sheeting. n. Hydraulic and air shores are to be installed according to manufacturer's tabulated data and specifications. Damaged shoring is to be evaluated by scene safety officer regarding its use. o. Shoring must be installed from the top down, with no rescuer going below waist deep past the last crossbrace installed. Air shore crossbraces may be toenailed in place (on the 2" x 6"). p. Rescue shoring should be on a 4-foot grid (cross braces every 4 feet both horizontally and vertically). q. Top cross braces should be within 2 feet of top. r. Bottom cross braces should be within 2½ feet of bottom. s. If you dig deeper than 2½ feet below bottom cross brace, you must add another brace. t. Dig gently, the patient may only be a few inches down. u. Rotate personnel often so they can continue to dig vigorously. 3  v. Remove all personnel from trench before raising patient (in case the raising operation disturbs the shoring). w. When the operation is finished, leave your shoring in place. OSHA will direct its removal. x. When the operation is a body recovery, not a rescue, slope the trench rather than shoring, if possible. C. IDOL/OSHA REGULATIONS 1. REQUIREMENTS It shall be the policy of the Fire Department that all employees assigned to the Department be required to conform with the requirements described in CFR OSHA 1926.650 both prior to, and during trench or excavation rescue operations. Employee safety must always come first. a. Although each soil condition carries its own requirements for providing protective systems, it shall be the policy of the Fire Department that the most conservative approach be taken. Rather than use the mandatory manual and visual test to clarify soil, all soils shall be considered "TYPE C" soils and must be protected as such. Soil conditions are classified as follows: Type A: Cohesive soil with an unconfined compressive strength of 1.5 tons per square foot (tsf) or greater (i.e.: clay). Type B: Cohesive soil with an unconfined compressive strength greater than 0.5 tsf but less than 1.5 tsf (ie: silty loam). Type C: Cohesive soil with an unconfined compressive strength of 0.5 tsf or less (i.e.: granular soils including gravel, sand and loamy sand). b. All underground installations are to be located and safeguarded (protected, supported, or removed) as necessary, to safeguard employees. c. A ladder must be located in all trenches 4 feet or deeper. The ladder must extend 3 feet above the top of the highest trench wall or the highest point of the protective device (whichever is greater). Ladders must be so located as to require no more than 25 feet of lateral travel. d. When exposed to traffic, employees shall wear warning vests or other clothing marked for high visibility. e. No one is permitted underneath loads handled by lifting or digging equipment. f. Personnel are required to stand away from any vehicle being loaded or unloaded. g. When mobile equipment is being operated adjacent to a trench and the operator does not have a clear view of the trench, use the following: 4  barricades, stop logs, or hand signals from an observer. h. If a hazardous atmosphere is suspected or exists within the trench, the atmosphere must be tested (for oxygen deficiency, flammability, and toxicity) prior to employees entering the trench. This is for all trenches greater than 4 feet. If a hazardous or deficient atmosphere exists, employees must be protected with appropriate respirators or ventilators must be used. If ventilators are used, continuous atmospheric monitoring is required. i. If water accumulation occurs in the trench, you must protect the trench from cave-in with special systems or remove the accumulated water with equipment. j. If the stability of adjacent structures is affected, systems such as bracing, shoring, or underpinning must be used on such structures. Sidewalks, pavements, curbs, and all appurtenant structures shall not be undermined unless a support system is used. k. The spoil pile, other stationary equipment or materials must be at least 2 feet from the edge of the trench. Fencing or other means must be used to keep the spoil pile from rolling into the trench. 2. PROTECTIVE SYSTEMS On all operations in trenches greater than 5' or with a potential for collapse, one or more of the three protective systems is to be determined to be used on the trench on the site and all appropriate equipment is to be obtained. a. Sloping and Benching 1) SLOPING - The sloping of the sides of the trench or excavation must be inclined away from the trench or excavation at an angle of 1.5 feet wide for every 1 foot in depth (Figure 1). 2) BENCHING - The benching of the sides of the trench or excavation must be inclined away from the trench or excavation benched with 4 feet horizontal and 2.5 feet vertical stops to the surface of the excavation (Figure 2). b. Shielding 1) The shield must extend at least to the top of the trench. If the shield is located below the trench mouth, the trench section is to be sloped at the above noted angle. 2) Employees are not allowed in shields during installation, removal, or movement of the shields within the trench. 5  3) Employees and escape ladders are only allowed within the shielded area. 4) All shields are to be used according to manufacturer's instructions. If multiple shields are used, they are to be connected using appropriate locking devices. c. Shoring (see Figure 3) 1) Manufacturer's specifications are to be maintained on the job site for all but timber systems. 2) Shoring equipment is to be maintained and used according to manufacturer's specifications. 3) If shoring equipment is damaged it must be examined by the competent person to evaluate its use. 4) As shoring is installed, the trench or excavation must be shored from the top of the excavation to the bottom, and removed in reverse order. 5) Shoring uprights must extend a minimum of 2" above the surface of the trench and must extend to the bottom of the trench. 6) Shoring uprights must not be farther apart than 4 feet (except timber shores). 7) Cross braces must be installed no greater than 4 feet apart (except timber shores). 8) Cross braces must not be greater than 2 feet from the top of the trench or excavation. 9) Cross braces must not be greater than 2.5 feet from the bottom of the trench. 10) When setting shores, no worker shall be lower than waist deep to the lowest cross brace. 11) All timber shore systems will be constructed in accordance with OSHA timber shoring tables. 6 Figure 1: SIMPLE SLOPING TYPE “C” SOIL 20’ Max. 1 1 1/2 Figure 2: BENCHING 7 Figure 3 DEFINITIONS EXCEPTIONS Where MABAS Illinois Policies and Procedures current online reference or MABAS 1 Operating Guidelines/Policy Statements are in conflict with HEFD Standard Operating Guidelines, HEFD Standard Operating Guidelines will take precedence. REFERENCES MABAS Illinois Policies and Procedures current online reference MABAS 1 Operating Guidelines/Policy Statements End of Document 8