Write a toolbox talk on trenching and excavation safety

Source excerpt

# Toolbox Talks Preventing Excavation/Trench Cave-ins - Ask the following questions and give time for answers. ## What are the hazards? Bodily or equipment entrapment in soil. ## What are the results? Broken or crushed limbs and bones, entrapment, suffocation, head injury, internal damage, and death. ## What should we look for? Stable rock and soil type (A, B, C), depth of excavation, cave-ins, water in trench, weather conditions (rain, frost), water table, protective systems, competent person, operation of heavy equipment near excavation, barricades, and falling loads. ## How do we prevent these results? • A competent person must evaluate excavations daily. Excavations should be re-evaluated after events such as rain. • Use shoring equipment, shielding, and/or sloping or benching systems for excavations greater than 5 feet in depth or less when deemed necessary by the competent person. • Examine protective systems in accordance with manufacturers recommendations and remove damaged systems from service. • Excavated material/other objects must be kept at least 2 feet from edge. ## Understanding Soil Types • Type "A" - most stable (clay, hardpan) • Type "B" - next most stable (slit, loam, unstable dry rock) • Type "C" - least stable (gravel, loamy sand) ## Let's talk about this site now How can you prevent cave-ins? Shoring, shielding, sloping, and/or benching. At what depth is cave-in protection required? 5 feet or less depending on the assessment by a competent person. Name some conditions that can increase cave-ins. Rain, heavy equipment, vibration, spoil piles, etc. The unfortunate reality - From 2011 to 2021 there were at least 220 trenching fatalities across the United States. These fatality incidents were preventable with the use of a protective system, proper employee training, and implementation of a safety and health management system. ## AN UNPROTECTED TRENCH IS AN EARLY GRAVE DOLI VIRGINIA DEPARTMENT OF LABOR AND INDUSTRY in li…

Source excerpt

# EXCAVATIONS AND TRENCHES WAC [redacted identifier] defines an excavation as "Any person-made cut, cavity, trench, or depression in the earth's surface, formed by earth removal." A trench is "A narrow excavation in relation to its length made below the surface of the ground. In general, the depth is greater than the width, but the width of a trench (measured at the bottom) is not greater than 15 feet. If forms or other structures are installed or constructed in an excavation so as to reduce the dimension measured from the forms or structure to the side of the excavation to 15 feet (4.6 m) or less (measured at the bottom of the excavation), the excavation is also considered to be a trench." One cubic yard of soil can weigh up to 3000 pounds - approximately the weight of a small car. The fatality rate for excavation work is 112% higher than the rate for general construction, according to data from the Occupational Safety and Health Administration (OSHA). The agency lists "employee injury from collapse" as the primary hazard of excavation work and includes "no protective system" among the leading causes of worker injuries. ## EXCAVATION AND TRENCHING HAZARDS Trenching and excavation work presents serious hazards to all workers involved. Cave-ins pose the most significant risk and are more likely than other excavation- related incidents to result in worker fatalities. One cubic yard of soil can weigh as much as a car. • Collapse of soils and materials (cave-in) due to lack of, inadequate, or weak protective systems • The striking or damaging of underground utility services • Persons falling into excavations due to a lack of barriers or inadequate fencing • Asphyxiation from toxic gases which have collected in the excavation/trench • Spoil (soil from excavation/trench) or materials/equipment being placed too close to the sides of the excavation/trench, which then become overloaded and collapse • Failure to check and maintain shoring, particularly after incle…

Source excerpt

CPWR TOOLBOX THE CENTER FOR CONSTRUCTION RESEARCH AND TRAINING TALK # Trench Safety When a trench caves in, the weight of the dirt can trap and kill workers. One cubic yard of dirt can weigh 3,000 pounds or more. Each year, trench collapses seriously injure or kill construction workers. In 2016, for example, 23 workers were killed in trench collapses. ## Jim, Nico, and Jose's Story Three laborers were working in an 8-foot-high wall trench. The walls were not shored-up. One side caved in, burying Nico and partially burying Jim. Jose managed to escape unharmed. Jim was pulled out. Nico suffocated and died. - How could this incident have been prevented? - Have you ever been in a trench cave-in? If so, what happened? : ## Remember This ➤ Never enter an unprotected or uninspected trench, even for a short task. A trained, competent person must inspect the trench and surroundings first. ➤Make sure you understand your employer's trench emergency program. ➤ Make sure rocks and dirt are kept at least 2 feet away from the top of the trench. - Never work alone in a trench and never without a lookout standing by. ➤ Make sure trench protection is provided by your employer. OSHA allows benching or sloping ground, shoring, or shielding with supports or trench boxes. How can we stay safe today? What will we do at the worksite to promote trench safety? 1. 2. OSHA Regulation: 1926.651(k)(1) ©2017, CPWR-The Center for Construction Research and Training. All rights reserved. CPWR is the research and training arm of NABTU. Production of this document was supported by cooperative agreement OH 009762 from the National Institute for Occupational Safety and Health (NIOSH). The contents are solely the responsibility of the authors and do not necessarily represent the official views of NIOSH. CPWR 【● THE CENTER FOR CONSTRUCTION RESEARCH AND TRAINING

Source excerpt

# Trench and Excavation Safety Trench collapses, or cave-ins, are the leading hazard in excavation work. Safe trenching helps prevent falls, falling loads, hazardous atmospheres, and incidents involving mobile equipment. ## Trench Safety Measures Trenches 5 feet or deeper require a protective system unless dug in stable rock. For trenches less than 5 feet, a competent person must decide if protection is needed. Trenches 20 feet or deeper must have a protective system designed or approved by a registered professional engineer, as required by OSHA 1926.652(b) and (c). ## Competent Person Before workers enter a trench, a competent person must inspect it daily and after any condition changes to ensure safety. This person is trained to identify hazards, determine soil types, select protective systems, and has the authority to correct issues immediately. ## Access and Egress • Keep heavy equipment and spoils at least 2 feet from trench edges - Locate underground utilities before digging • Test for atmospheric hazards in trenches over 4 feet deep • Inspect trenches daily, at the start of each shift, after storms, and after conditions change • Never work under suspended loads - Wear high visibility clothing when near traffic # Protective Systems • Benching: a method of protecting workers from cave-ins by cutting the sides of an excavation into horizontal steps. Benching is not allowed in Type C soil. • Sloping: involves cutting back the trench wall at an angle inclined away from excavation. • Shoring: requires installing aluminum hydraulic or other types of supports to prevent soil movement and cave-ins. • Shielding: protects workers by using trench boxes or supports to prevent cave-ins. Designing these systems can be complex, as factors like soil type, trench depth, moisture, weather, nearby loads, and site activity must all be considered. OSHA standards require that employers provide workplaces free of recognized hazards. The employer must compl…

Source excerpt

Trench Safety Working in an unprotected trench is dangerous - Protect workers from cave-ins when trenches are at least 5' deep and from shallower trenches where a cave-in hazard exists. - o Do this by supporting the walls with shoring, shielding workers with trench boxes, or sloping the walls back wide enough, per the OSHA Excavation Standard. - o Protect employees from water accumulation by pumping out ground or utility water. - Provide ladders to workers when working in trenches of at least 4'. Call Dig Safe at 1-(888) 344-7233 to identify underground utilities. Ensure that workers wear high-visibility clothing when working around vehicle traffic. - Use Part 6 of the Manual on Uniform Traffic Control Devices to determine appropriate work zone signage and traffic channeling devices. • Spoils must be placed 2 feet from the trench edge. • Do not allow employees to work under suspended or raised loads or materials. A competent person must inspect each trench worksite, including the soil protective system, before the start of work, and again if there is a hazard-increasing change in conditions, like a rainstorm. ## Resources from the Department of Labor Standards Download a copy of our Trench Template Program and Inspection Worksheet at mass.gov/doc/trench-template-program-and-worksheet ## For more information, visit mass.gov/dls MASSACHUSETTS DEPARTMENT OF MASSsafety Works! LABOR STANDARDS Workplace Safety is No Accident 3-20-24

Source excerpt

# SafetyWorks! Toolbox Talks # Subject: Excavations Cave-ins are a major cause of deaths in the construction industry each year. Excavations must be properly shored or cut back to an acceptable angle of repose; otherwise, there will be a constant threat of a cave-in and the associated chance of injury or loss of life. A qualified person must be involved in planning and having a safe excavation project. ## Guide for Discussion Before Excavation Review • Underground utilities located? (Checked with local utility companies or property owner.) Call Dig-Safe • Any overhead hazards (i.e., falling rock, soil, or other materials or equipment)? • Will there be any heavy equipment operating in the near proximity of the excavation? • Estimated depth required for the excavation? • How many people will work inside the excavation? • Is there an escape plan for those inside the excavation to cover a possible cave-in or slide? • Has there been a soil analysis? This will help determine the type of shoring to provide or the angle of repose needed. ## Steps to Take to Provide a Safe Excavating Operation • Always shore or cut back the opening adequately. • Any opening with a depth of five feet or more requires shoring or be cut back. • Never store excavated or other materials closer than two feet from the edge of the excavation (spoil pile). • Inspect the excavation daily. This must be done by a competent person. • Access ladders must be provided every twenty-five feet in excavations of four (4) feet or more in depth. • Never work outside of the shoring or trench box • Review escape procedures with all personnel who may have cause to be in the excavation. ## Additional Discussion Notes: Possible gas accumulation in the excavation? Barriers, guardrails or other safety warnings in excavation area? NOTE: Region I OSHA requires safety compliance officers to stop and examine all open trenches SafetyWorks! 45 State House Station Augusta, Maine [redacted postal code] P…

Source excerpt

# Trenching and excavation safety (cont.) ## General trenching and excavation rules (cont.) • Test for atmospheric hazards, such as low oxygen, hazardous fumes and toxic gases when greater than four feet deep. • Inspect trenches at the start of each shift and following a rainstorm or other water intrusion. • Do not work underneath suspended or raised loads and materials. • Inspect trenches after any occurrence that could have changed conditions in the trench. • Ensure personnel wear high-visibility or other suitable clothing when exposed to vehicular traffic or mobile earth-moving equipment. ## Protective systems There are different types of protective systems – sloping, shoring and shielding. <table><tr><th>Type of protective system</th><th></th><th>Illustration of system</th></tr><tr><td>Sloping involves cutting back the trench wall at an angle inclined away from the excavation.</td><td>20 MAX</td><td></td></tr><tr><td>Shoring requires installing aluminum hydraulic or other types of supports to prevent soil movement and cave-ins.</td><td></td><td></td></tr><tr><td>Shielding protects workers by using trench boxes or other types of supports to prevent soil cave-ins. Designing a protective system can be complex because many factors must be considered: soil classification; depth of cut; water content of soil; changes caused by weather or climate; surcharge loads (spoil, other materials to be used in the trench); and other operations in the vicinity.</td><td></td><td></td></tr></table> ## More information To learn more about excavation safety, view the standards at osha.gov. Revised March 2025

Source excerpt

# Tennessee OSHA's Special Emphasis Program on Trenching & Excavation Because trenching and excavation collapse is deadly and often involves multiple victims, Tennessee OSHA has established a special emphasis program to focus attention and resources on these hazards. It is impossible to predict when an excavation or trench will collapse. The sudden collapse of the walls makes escape almost impossible. The only way to prevent collapse is to slope or shore the walls or install a trench shield and follow the TOSHA trenching and excavation standards contained in 29 CFR 1926 Subpart P. Under this special emphasis program, all TOSHA compliance and consultative services personnel will be on the lookout for trenching or excavation work sites. Personal observation, reports of imminent danger, fatality/catastrophe reports, safety and health agency referrals, employee complaints, and media reports are also used to locate trenching and excavation work. Each occurrence is handled with an appropriate intervention by TOSHA. ## Hazards on the Excavation Site Excavation workers are exposed to many hazards, but the chief hazard is cave-in. TOSHA requires that all employees exposed to potential cave-ins be protected by sloping or benching the sides of the excavation, shoring the sides of the excavation, or placing a shield between the sides and the work area. In addition to cave-in hazards, workers must also be protected from adjacent utility lines, exposure to vehicular traffic, falling loads, hazardous atmospheres, and fall hazards. Utility lines such as gas, electrical, sewer, and water must be located and supported prior to placing employees in an excavation. Employees working in, or near, roadways must wear high visibility vests. Workers are not to work beneath suspended loads, and walkways crossing excavations must be equipped with guardrails. Precautions, including atmospheric testing and emergency rescue procedures and equipment, must be taken when workers enter excavat…