Giuliano bozzo moncada spanishexcavations 10 hr_construction (2)

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• #2: I. Introduction A. According to OSHA construction safety and health standards, a trench is a narrow excavation made below the surface of the ground and having a depth greater than the width (the width does not exceed 15 feet). B. An excavation is defined as any man-made cut, cavity, trench or depression in the earth's surface formed by earth removal. This can include anything from cellars to highways.
• #3: I. Introduction A. According to OSHA construction safety and health standards, a trench is a narrow excavation made below the surface of the ground and having a depth greater than the width (the width does not exceed 15 feet). B. An excavation is defined as any man-made cut, cavity, trench or depression in the earth's surface formed by earth removal. This can include anything from cellars to highways.
• #4: I. Introduction A. According to OSHA construction safety and health standards, a trench is a narrow excavation made below the surface of the ground and having a depth greater than the width (the width does not exceed 15 feet). B. An excavation is defined as any man-made cut, cavity, trench or depression in the earth's surface formed by earth removal. This can include anything from cellars to highways.
• #5: I. Introduction A. According to OSHA construction safety and health standards, a trench is a narrow excavation made below the surface of the ground and having a depth greater than the width (the width does not exceed 15 feet). B. An excavation is defined as any man-made cut, cavity, trench or depression in the earth's surface formed by earth removal. This can include anything from cellars to highways.
• #6: C. Students should be able to: 1. List the specific requirements of excavation safety. 2. List the options available for sloping and benching systems. 3. List the options available for the design of protective systems. 4. List the requirements for the installation and removal of support systems.
• #8: II. Specific Requirements - 1926.651 A. Surface encumbrances must be removed or supported to safeguard employees. B. These include things such as telephone or light poles, signs, trees, walls, parking lots or sidewalks.
• #9: C. Prior to opening an excavation, the employer must determine the location of underground installations. They can do this by contacting local utility companies or owners of the property. If the exact location cannot be determined or response does not come within 24 hours, work can proceed if: 1. The employer does so with caution 2. Detection equipment or other acceptable means is used to locate utility installations D. When operations approach the estimated location of underground installations, the exact location must then be determined. E. While any excavation is open then underground installations must be protected, supported or removed to protect workers.
• #10: G. If an excavation is 4 feet or more in depth, a stairway, ladder, ramp or other safe means of egress must be used.
• #11: F. Ramps and runways used solely for access and egress must meet the following requirements: 1. Be designed by a competent person. 2. Have structural members connected if using two or more and make them uniform. 3. Runways must have connecting cleats that do not cause a tripping hazard. 4. Ramps used in lieu of steps must have cleats or surface treatment to top surface to prevent slipping.
• #12: H. If an employee is exposed to vehicular traffic, they must be provided with and wear warning vests or other suitable garments which have a reflective surface or are highly visible.
• #13: I. To protect workers from falling loads, they must: 1. Never work underneath loads; 2. Stand away from vehicles being loaded or unloaded; and 3. Vehicle drivers may stay in vehicle when vehicle provides adequate protection.
• #14: J. When mobile equipment approaches an excavation and the driver does not have a clear view of the operations, one of the following warning systems must be in place to protect the workers: 1. Barricades; 2. Hand or mechanical signals; 3. Stop logs; or 4. Grade away from the excavation to protect the location.
• #15: K. To protect workers from exposure to harmful levels of atmospheric contaminants and assure acceptable atmospheric conditions, the following requirements must be met: 1. Test oxygen deficient atmospheres (< 19.5% oxygen)where the excavation is greater than4 feet deep. 2. Use proper respiratory protection or ventilation IAW Subparts D and E. 3. Provide ventilation if the atmosphere contains flammable gas which exceeds 20% of the Lower Flammable Limit (LFL) of the gas. 4. Test as often as necessary to ensure safe atmospheric conditions are maintained.
• #16: K. To protect workers from exposure to harmful levels of atmospheric contaminants and assure acceptable atmospheric conditions, the following requirements must be met: 1. Test oxygen deficient atmospheres (< 19.5% oxygen)where the excavation is greater than4 feet deep. 2. Use proper respiratory protection or ventilation IAW Subparts D and E. 3. Provide ventilation if the atmosphere contains flammable gas which exceeds 20% of the Lower Flammable Limit (LFL) of the gas. 4. Test as often as necessary to ensure safe atmospheric conditions are maintained.
• #18: L. Emergency rescue equipment must be readily available at locations where hazardous atmospheric conditions exist or could exist . The equipment has to be attended at all times during operations. M. A harness and lifeline is required by all workers entering the following: 1. Bell bottom pier holes; or 2. Any other similar deep and confined footing excavation. This lifeline must be separate from all other lines and attended constantly while the worker is in the excavation.
• #20: N. If there is water accumulation in the excavation, no work can take place unless one of the following occurs: 1. A support or shield system is installed; 2. A water removal system is in place and monitored by competent person; or 3. A safety harness and lifeline being used. O. If excavation interrupts the natural drainage of surface water, such as a stream, certain precautions, such as diversion ditches, dikes, or other suitable means to prevent surface water from entering the excavation and allow drainage to an area adjacent to the excavation, must be in place. P. If the excavation is subject to runoff from heavy rains, then it must be inspected by a competent person before any work takes place.
• #21: If the stability of buildings or structures adjoining an excavation are endangered by the operations, they must be stabilized by support systems such as shoring, bracing or underpinning. R. If an excavation below the base or footing of foundation or retaining wall would endanger workers, they may not work in the excavation unless: 1. A support system is in place; 2. The excavation is in stable rock; or 3. A registered professional engineer has approved that the structure is far enough away from the excavation to pose no hazard. S. Never undermine sidewalks, pavement, etc. unless a support system or other method of protection is in place to prevent collapse.
• #22: T. To prevent loose rock or soil from falling or rolling into an excavation, use scaling to remove loose material, install protective barricades or provide other means of protection. All such materials must be kept at least two feet from the excavation at all times.
• #23: U. Inspections of all areas of the operations must be made daily by a competent person. The inspections should be made before the start of work and periodically throughout the day. If rainstorms or other hazards occur, inspect the area immediately. The competent person may also shut down operations if any hazards are found. Workers must be removed from the area until these hazards have been abated.
• #24: U. Inspections of all areas of the operations must be made daily by a competent person. The inspections should be made before the start of work and periodically throughout the day. If rainstorms or other hazards occur, inspect the area immediately. The competent person may also shut down operations if any hazards are found. Workers must be removed from the area until these hazards have been abated.
• #25: Reference 1926.650(b) "Competent person" One who is capable of identifying existing and predictable hazards in the surroundings, or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them. Preamble Page 45909 – “Competent Person” The term is used throughout existing subpart P, but was not defined within the subpart, and there were no references to the existing definition in subpart C, in the proposal, OSHA added the definition to subpart P to help those using the standard.
• #26: Reference 1926.651(k) (2) Where the competent person finds evidence of a situation that could result in a possible cave-in, indications of failure of protective systems, hazardous atmospheres, or other hazardous conditions, exposed employees shall be removed from the hazardous area until the necessary precautions have been taken to ensure their safety.
• #28: V. Walkways must be provided where workers or equipment cross over excavations. When walkways are six feet or more above the lower levels, a guardrail that complies with 1926.502 must be in place. W. Barrier protection must be provided at all remotely located excavations such as wells, pits, shafts, etc. These operations must be backfilled once work is completed.
• #29: III. Protective Systems - 1926.652 A. All workers must be protected from cave-ins unless the excavation: 1. Is in stable rock; or 2. Is less than five feet in depth and a competent person determines there is no indication of potential cave-in. All protective systems used for this protection must have the capacity to resist, without failure, any loads that are applied to them.
• #30: B. Definitions that apply to this section: 1. Benching System - a method of protecting employees from cave-ins by excavating sides to form one or a series of horizontal levels or steps, usually with vertical or near vertical surfaces between levels. 2. Sloping System - a method of protecting employees from cave-ins by excavating to form sides of an excavation that are inclined away from the excavation so as to prevent cave-ins. The angle of incline required to prevent a cave-in varies with differences in such factors as the soil type, environmental conditions of exposure, and application of surcharge loads. C. There are four options available during excavations. Option 1 allows for configurations and slopes. The employer must configure in the following manner: 1. Slopes at an angle not steeper than one and one-half horizontal to one vertical (34 degrees measured from the horizontal); and 2. Must form configurations that are in accordance with Type C soil in Appendix B. D. Option 2 allows the employer to determine slopes and configurations using Appendices A and B.
• #31: E. Option 3 allows the employer to use tabulated data such as tables or charts. This data must be in writing and include the following: Identification of the parameters that affect the selection of a sloping or benching system drawn from the data; 2. Identification of the limits of use of the data, to include the magnitude and configuration of slopes determined to be safe; and 3. Any explanatory information that would aid the user in making a decision on the protective system to use. A copy of the tabulated data must be kept at the jobsite and must identify the registered professional engineer who approved the design.
• #32: F. Option 4 allows the employer to use a design done by a registered professional engineer. This data must be in written form and include the following: 1. The magnitude of the slopes that were determined to be safe for the project; 2. Configurations determined to be safe for the project; and 3. Identity of the registered professional engineer approving the design. One copy must be kept at the jobsite until the slope is constructed
• #33: G. If using Option 1, designs for timber shoring must meet the conditions and requirements of Appendices A and C. If using aluminum hydraulic shoring, use the manufacturers' tabulated data or Appendix D.
• #34: H. If using Option 2, the employer must follow all of the manufacturer’s tabulated data. Any deviation from this data must have the manufacturer’s written approval. Again, a written copy of the data must be kept at each jobsite during construction of the protective system and then offsite afterward.
• #35: I. If using Option 3, the employer must again use only the data from tables and charts. The data must be in writing and include: 1. Identification of the parameters that affect the selection of a protective system drawn from such data; 2. The limits of use of the data; 3. Any explanatory information that would aid the user in making a decision on the protective system to use; and 4. Identity of the registered professional engineer approving the design. A copy of the data must be kept at the jobsite during construction of the protective system and offsite afterward.
• #36: J. If using Option 4, all designs must be approved by a registered professional engineer. The designs must be in writing and include: 1. A plan indicating sizes, types and configurations of the materials to be used in the protective system; and 2. The identity of the registered professional engineer who approved the design. One copy must be kept at the jobsite during construction of the protective system and then offsite afterward.
• #37: K. All materials used for protective systems must be free of damage or defects that could impair proper function. If using manufactured materials and equipment, follow the manufacturer's recommendations for care and use. L. If the equipment or material is damaged then a competent person must examine and determine suitability for continued use. If the competent person cannot determine usability or if it is damaged, then a registered professional engineer must evaluate and approve it for return to service.
• #38: M. When installing or removing support systems, the following procedures must be followed: 1. Members of support system must be securely connected to avoid sliding, falling, kickouts, or other predictable failures; 2. The system must protect employees from cave-ins, structural collapses or being struck by members; 3. Never subject the system to loads which exceed their designed limits;
• #39: 4. Additional precautions must be taken to protect the workers if the system must be temporarily removed; 5. Removal of the system must always begin at the bottom of the excavation and performed slowly to prevent possible failures of the system; and 6. Backfilling must progress with the removal of the support systems.
• #40: N. There are additional requirements that must be considered for the use of support systems for trench excavations: 1. Excavation of material is permitted up to two feet below the bottom of the support system as long as the system is designed to account for the full depth of the trench. There must also be no indication that there is a chance of a loss of soil from behind or below the bottom of the support system. while the trench is open. 2. Installation of a support system must be closely coordinated with the excavation of trenches.
• #41: O. If employees work on the faces of sloped or benched excavations, then all employees working below them must be protected from the hazard of falling, rolling, or sliding material or equipment.
• #42: P. When using shield systems on excavations, the following requirements apply: 1. The systems must never be subjected to loads beyond those they were designed to withstand; 2. The shield must be installed to restrict lateral or other hazardous movement of the system in the event unexpected loads occur; 3. Workers must be protected from cave-ins when entering or exiting the areas protected by the shields; and 4. No employees are allowed in the shields during vertical installation, removal or other movement.
• #45: Reference 1926.651(c(1) Structural ramps - Structural ramps that are used solely by employees as a means of access or egress from excavations shall be designed by a competent person. Structural ramps used for access or egress of equipment shall be designed by a competent person qualified in structural design, and shall be constructed in accordance with the design. - Ramps and runways constructed of two or more structural members shall have the structural members connected together to prevent displacement. - Structural members used for ramps and runways shall be of uniform thickness. - Cleats or other appropriate means used to connect runway structural members shall be attached to the bottom of the runway or shall be attached in a manner to prevent tripping. - Structural ramps used in lieu of steps shall be provided with cleats or other surface treatments o the top surface to prevent slipping.
• #46: Reference 1926.651(c) and 1926.1053 (ladder)
• #47: Reference 1926.652(a) and 1926.652(c)(1) Designs for aluminum hydraulic shoring shall be in accordance with paragraph (c)(2), but if manufacturer's tabulated data cannot be utilized, designs shall be in accordance with appendix D. Employees exposed to potential cave-ins must be protected by sloping or benching the sides of the excavation, by supporting the sides of the excavation, or by placing a shield between the side of the excavation and the work area. 1926 Subpart P Appendix D Aluminum Hydraulic Shoring for Trenches Contains information that can be used when aluminum hydraulic shoring is provided as a method of protection against cave-ins in trenches that are not more than 20 feet deep.
• #48: Reference 1926.652(a) and (b) and (c)
• #49: V. Summary A. Trenching and excavation work presents serious risks to all workers involved. The greatest risk is the cave-in. Compliance with the standard will prevent or greatly reduce the risk of these cave-ins as well as other excavation-related accidents. B. Think before you work in any trench or excavation. Don't be like the dope on a rope.