TRENCH AND EXCAVATION SAFETY GUIDE I. POLICY A. PURPOSE The purpose of the Excavation and Trenching Safety Program is to put into place work practices and procedures that will protect workers from the hazards that may be found in or around excavations or trenches. B. DUTIES AND RESPONSIBILITIES 1. Designated Supervisors shall: a. Work with the Safety Supervisor and Engineer in preparing and implementing all provisions of the Trenching and Shoring Plan for work areas under their control; b. Receive training for “Competent Person” for trenching as defined by Cal/OSHA. c. Act as the “Competent Person” for excavation sites under their control; d. Assure that the equipment necessary to complete an excavation safely is available and in good condition; e. Assure that all underground utility installations such as sewer, telephone, fuel tanks, electric, gas, and water lines are located and marked before excavation begins; f. Conduct soils tests to determine soil type; g. Ensure that underground installations are protected, supported or removed while the excavation is open; h. Ensure worker protection and compliance with other applicable safety plans, programs and guidelines; i. Ensure protection of the public with appropriate barricades; j. Determine what protective systems will be used to prevent cave-ins; and, k. Conduct daily inspections of excavations, the adjacent areas, and protective systems for evidence of a situation that could result in possible cave-ins, indications of failure of protective systems, hazardous atmospheres or other hazardous conditions. 2. Employees shall: a. Complete all safety training requirements and request further instruction if unclear on any part of the Trenching and Shoring Plan; Glendale Water & Power Department – Safety Program Page 1 of 21 Ch 41 – Trench and Excavation Safety Guide – Revised September 2018 H:/Public/Safety Manual b. Use appropriate safety and personal protective equipment (PPE); c. Adhere to the requirements of the Trenching and Shoring Plan; and, d. Report all work place injuries and unsafe conditions. 3. Safety Supervisor a. Provide consultation b. Work with the designated Supervisor/Competent person or Engineer in preparing the Trenching and Shoring Plan with periodic review and revisions as needed; c. Distribute the Trenching and Shoring Plan to all affected individuals; d. Investigate and document all reported accidents and/or near-miss accidents that are directly or indirectly related to trenching; and receive training as” Competent Person” to assist the designated Supervisor in developing the Trenching and Shoring Plan. e. Coordinate training and retraining of those who may be involved in excavations. II. TRAINING All personnel involved in trenching or excavation work shall be trained in the requirements of this plan. Training shall be performed before anyone is assigned duties in excavations. A. TRAINING OF THE DESIGNATED SUPERVISOR 1. All Designated Supervisors of trenches and excavations shall meet the Cal/OSHA requirements for a “Competent Person.” 2. Designated Supervisors will attend a “Competent Person” training course. B. TRAINING OF WORKERS Personnel who perform work in excavations shall comply with the requirements of this plan and receive appropriate training that shall include at a minimum: 1. Safe work practices that must be followed during work in excavations. 2. The use of personal protective equipment (PPE) that will typically be required during work in excavations, including but not limited to safety shoes, hardhats, and fall protection devices; 3. Procedures to be followed if a hazardous atmosphere exists or could reasonably be expected to develop during work in an excavation; and 4. Emergency and non-entry rescue methods, and procedures for calling rescue services. Glendale Water & Power Department – Safety Program Page 2 of 21 Ch 41 – Trench and Excavation Safety Guide – Revised September 2018 H:/Public/Safety Manual C. RETRAINING Retraining will be performed whenever site inspections conducted by the Designated Supervisor or the Safety Office indicate that a worker does not have the necessary knowledge or skills to safely work in or around excavations. III. EXCAVATION PROCEDURES A. PRE-WORK SITE INSPECTION Prior to excavation the site shall be thoroughly inspected by the Designated Supervisor to determine if special safety measures must be taken. (See Appendix A.) B. SURFACE ENCUMBRANCES All equipment, materials, supplies, permanent installations (for example, buildings or roadways), trees, brush, boulders, and other objects at the surface that could present a hazard to employees working in the excavation shall be removed or supported as necessary to protect employees. C. UNDERGROUND UTILITIES 1. The location of sewers, telephone, fuel, electric, water lines, or other underground installations that may be encountered during excavation work shall be determined and marked prior to opening an excavation. 2. The Underground Service Alert (Dig Alert) will be contacted to request marking of all existing underground utilities. (Call 811 – Toll Free.) See Appendix B. 3. If the nature of the emergency requires the initiation of the excavation prior to the placement of utility location markings, all excavation shall be done with the assumption that other utilities exist in the area. 4. Utilities left in place shall be protected by barricades, shoring, suspension or other means as necessary to protect employees. 5. When constructing substructures around an existing duct line, the cables and/or duct lines containing cables shall be properly supported and protected from physical damage. 6. Movement and rerouting of cables shall be done by qualified workers. D. CHIPPING CONCRETE 1. Personal protective devices such as goggles, protective face shields with eye protection, foot shields, and hearing protection shall be worn when appropriate for the chipping operations. 2. Caution shall be exercised not to strike electric or telephone conduits, gas lines or other substructures when working in tunnels or trenches. Glendale Water & Power Department – Safety Program Page 3 of 21 Ch 41 – Trench and Excavation Safety Guide – Revised September 2018 H:/Public/Safety Manual 3. When chipping around a duct line containing energized high-voltage conductors (600 volts and above), an “OK – TO WORK HOT” shall be obtained and a second qualified person shall be present and shall act as a safety observer. 4. Exercise extreme caution while exposing duct. Consider that all conduits contain energized cables until proven otherwise. 5. Cables adjacent to a chipping operation shall be de-energized when possible and protected, as the hazard requires. 6. Consult the Electrical Services Section Rule No.6 (Chapter 44) for more guidelines on conduit chipping procedure, when working on electrical services projects. E. ADJACENT STRUCTURES Excavations adjacent to buildings, walls, or other structures shall not commence until support for such facilities has been provided. If the ability of the side slopes of the excavation to support such structures is in question, the excavation shall not proceed until a registered professional engineer has determined that the excavation will not pose a hazard to the workers or to the stability of the structure. F. PROTECTION OF THE PUBLIC 1. Barricades, walkways, lighting and posting shall be provided as necessary for the protection of the public prior to the start of excavation procedures. 2. Guardrails, fences, or barricades shall be provided on excavations adjacent to walkways, driveways and other pedestrian or vehicle thoroughfares. Warning lights or other illumination shall be maintained as necessary for the safety of the public and employees from sunset to sunrise. G. SURFACE CROSSINGS Surface crossing of trenches should be discouraged; however, if trenches must be crossed, such crossings are permitted only under the following conditions: 1. Vehicle crossings must be designed by and installed under the supervision of a registered professional engineer. 2. Walkways or bridges must be provided for foot traffic. These structures shall: a. have a safety factor of 4; b. have a minimum clear width of 20 in (0.51 m); c. be fitted with standard rails; and d. extend a minimum of 24 in (.61 m) past the surface edge of the trench. H PROTECTION OF WORKERS IN EXCAVATIONS 1. Access and Egress a. Stairs, ladders or ramps shall be provided where workers are required to enter trench excavations over 4 feet deep. b. A means of exit shall be provided every 25 feet of trench length. Glendale Water & Power Department – Safety Program Page 4 of 21 Ch 41 – Trench and Excavation Safety Guide – Revised September 2018 H:/Public/Safety Manual c. Ladders must be secured and extend a minimum of 36 inches above the landing. (See Chapter 33, Ladders, for general information and inspection requirements.) I. VEHICULAR TRAFFIC When the work area is in or adjacent to a vehicular right of way, all workers shall be provided with and shall wear high visibility vests or other suitable garments. (See Chapter 37, Traffic Control.) J. FALLING LOADS 1. Workers shall stand away from loading or unloading operations to avoid being struck by spillage or falling materials. 2. No worker shall be permitted underneath loads being handled by lifting or digging equipment. K. SOIL FALL HAZARD 1. Workers doing work in an excavation shall be protected from falling rock or soil. 2. Side slopes of the excavation (trench) shall be scaled to remove loose material and protective covering added as necessary to prevent material from falling. 3. Excavated spoil and equipment shall be placed at least two feet from the edge of excavations and/or sufficiently restrained in order to prevent movement into the excavation. L. WARNING SYSTEM FOR MOBILE EQUIPMENT A warning system shall be used when mobile equipment is operated next to the edge of an excavation if the operator does not have a clear, direct view of the edge of the excavation. M. WORKING DISTANCE 1. A safe working distance shall be maintained from other workers to avoid being struck by their tools. 2. Workers shall not work where they are out of sight or more than 50’ from other workers.