Knowledgebase-Excavation Safety Policy Ordinance
TOWN OF WARTRACE, TENNESSEE
AN ORDINANCE AMENDING THE WARTRACE MUNICIPAL CODE
BE IT ORDAINED BY THE BOARD OF MAYOR AND ALDERMEN OF THE TOWN OF WARTRACE, TENNESSEE:
Section 1. The Wartrace Municipal Code is hereby amended by adding Chapter 9 to Title 4 to read in its entirety as follows:
EXCAVATION SAFETY POLICY
I.Purpose. Trenching and excavation work poses serious risks to all workers involved. The primary hazard, however, for excavation workers, is from cave-ins. When cave-ins occur, they are much more likely to result in worker fatalities than other excavation-related accidents. The Town of Wartrace has developed these policies and procedures and requires strict compliance to prevent or greatly reduce the risk of cave-ins as well as other excavation-related accidents.
The Occupational Safety and Health Administration (OSHA) requires that employees exposed to cave-in hazards be protected by (1) sloping or benching the sides of the excavation, (2) by supporting the sides of the excavation, or (3) by placing a shield between the side of the excavation and the work area.
II. Trench Excavations
A. Sloping. The safety and health of excavation workers can be ensured by effectively sloping the sides of a trench or excavation to an angle not steeper than one and one-half horizontal to one vertical (34 degrees measured from the horizontal). A slope of this gradation or less is considered safe for any type of soil.
All simple slope excavations of 16 feet or less in depth shall have a maximum allowable slope of 1 and 1/2:1. Any excavations of greater depth than 16 feet will be undertaken by an outside contractor.
B. Trench Boxes and Shields. Trench boxes and shields designed or approved by a registered professional engineer, or based on data prepared or approved by a registered professional engineer, may be used to ensure the safety of excavation workers. Trench boxes may be constructed of timber, aluminum, or other suitable material as may be approved by a registered professional engineer.
C. Responsibility. It shall be the responsibility of the town=s public works supervisor or to ensure that all excavations, where city employees are carrying out the excavation, or a contractor employed by the city, are carried out using either the sloping or trench boxes and shield safety methods. Under no circumstances shall the supervisor or manager permit an excavation of more than four feet in depth without using proper sloping or trench boxes and shields, unless the public works supervisor has determined that the excavation is made entirely in stable rock, is less than four feet deep, or an examination of the ground finds no indication of a potential cave-in.
III. Safety Precautions
A. Stability of Structures. Adjacent structures such as buildings, walls, sidewalks or pavements shall be shored, braced, or underpinned to ensure stability. Excavations shall not be undertaken below the level of the base or footing of any foundation or retaining wall unless (1) a support system such as underpinning is provided, (2) the excavation is in stable rock, or (3) a registered professional engineer determines that the structure is sufficiently removed from the excavation and that the excavation will not pose a hazard to employees.
Excavations under sidewalks and pavements are also prohibited unless an appropriately designed support system is provided.
B.Installation and Removal of Protective Systems.
Installing support systems shall be undertaken in accordance with the following procedures for the protection of employees:
* Securely connect members of support systems,
* Safely install support systems,
* Never overload members of support systems, and
* Install other structural members to carry loads imposed on the support system when temporary removal of individual members is necessary.
Excavations of 2 feet or less below the bottom of the members of a support or shield system of a trench may be undertaken if (1) the system is designed to resist the forces calculated for the full depth of the trench, and (2) there are no indications, while the trench is open, of a possible cave-in below the bottom of the support system. Also, the installation of support systems must be closely coordinated with the excavation of trenches.
Upon completion of the work, the excavation should be back filled as the protective system is dismantled. After the excavation has been cleared, workers should slowly remove the protective system from the bottom up, taking care to release members slowly.
C. Materials and Equipment.
The Town of Wartrace is responsible for the safe condition of materials and equipment used for protective systems. Defective and damaged materials and equipment can result in the failure of a protective system and cause excavation hazards.
The public works supervisor of the Town of Wartrace must ensure that (1) materials and equipment are free from damage or defects, (2) manufactured materials and equipment are used and maintained in a manner consistent with the recommendations of the manufacturer and in a way that will prevent employee exposure to hazards, and (3) while in operation, damaged materials and equipment are examined by a competent person to determine if they are suitable for continued use. If materials and equipment are not safe for use, they must be removed from service. These materials cannot be returned to service without the evaluation and approval of a registered professional engineer.
IV. Other Hazards
A. Exposure to Falls, Falling Loads, and Mobile Equipment.
In addition to cave-in hazards and secondary hazards related to cave-ins, there are other hazards from which workers must be protected during excavation-related work. These hazards include exposure to falls, falling loads, and mobile equipment. To protect employees from these hazards, the public works supervisor shall take the following precautions:
* Keep materials or equipment that might fall or roll into an excavation at least 2 feet from the edge of excavations, or have retaining devices, or both.
* Provide warning systems such as mobile equipment, barricades, hand or mechanical signals, or stop logs, to alert operators of the edge of an excavation. If possible, keep the grade away from the excavation.
* Provide scaling to remove loose rock or soil or install protective barricades and other equivalent protection to protect employees against falling rock, soil, or materials.
* Prohibit employees from working on faces of sloped or benched excavations at levels above other employees unless employees at lower levels are adequately protected from the hazard of falling, rolling, or sliding material or equipment.
* Prohibit employees under loads that are handled by lifting or digging equipment. To avoid being struck by any spillage or falling materials, require employees to stand away from vehicles being loaded or unloaded. If cabs of vehicles provide adequate protection from falling loads during loading and unloading operations, the operators may remain in them.
B. Water Accumulation
Employees are prohibited from working in excavations where water has accumulated or is accumulating unless adequate protection has been taken. If water removal equipment is used to control or prevent water from accumulating, the equipment and operations of the equipment must be monitored by a competent person to ensure proper use.
Diversion ditches, dikes, or other suitable means shall be used to prevent surface water from entering an excavation and to provide adequate drainage of the area adjacent to the excavation. The supervisor of public works must inspect excavations subject to runoffs from heavy rains.
C. Hazardous Atmospheres
The public works supervisor shall test excavations greater than 4 feet in depth as well as ones where oxygen deficiency or a hazardous atmosphere exists or could reasonably be expected to exist, before an employee of the city enters the excavation. If hazardous conditions exist, controls such as proper respiratory protection or ventilation must be provided. Controls used to reduce atmospheric contaminants to acceptable levels must be tested regularly.
Where adverse atmospheric conditions may exist or develop in an excavation, the employer also must provide and ensure that emergency rescue equipment, (e.g., breathing apparatus, a safety harness and line, basket stretcher, etc.) Is readily available and attended when used.
When an employee of the town enters bell-bottom pier holes and similar deep and confined footing excavations, the employee must wear a harness with a lifeline. The lifeline must be securely attached to the harness and must be separate from any line used to handle materials. While the employee wearing the lifeline is in the excavation, an observer must be present to ensure that the lifeline is working properly and to maintain communication with the employee.
D. Access and Egress
The Town of Wartrace must provide safe access and egress to all excavations. When employees are required to be in trench excavations 4 feet deep or more, adequate means of exit, such as ladders, steps, ramps or other safe means of egress, must be provided and be within 25 feet of lateral travel. If structural ramps are used as a means of access or egress, they must be designed by a professional engineer if used for employee access or egress, or a competent person qualified in structural design if used by vehicles. Structural members used for ramps or runways must be uniform in thickness and joined in a manner to prevent tripping or displacement.
Section 2. This ordinance shall become effective upon final passage, the public welfare requiring it.
Passed this: First Reading:__________________________