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QuickCard® (English/Spanish) offers tips to employers OSHA‘s and employees on improving workplace safety and health while working in trenches. This QuickCard® can be found at http://www.osha.gov/Publications/quickcard/trenching_en.pdf.
EMPLOYEES REMOVED FR OM EXCAVATION SITE M INUTES BEFORE COLLAP SEOSHA's role in the life of the American worker was exhibited once again when, at 10 a.m. on the morning of June 6 in Brooklyn, N.Y., OSHA Compliance Safety and Health Officer Bob Stewart requested that six construction employees be removed from a 22-foot deep excavation due to the hazardous 10-ton concrete abutment hanging above it. Fifteen minutes later, the overhang collapsed and fell, landing in the exact spot in which the employees had been working. Stewart is a safety specialist assigned to OSHA's Manhattan Area Office in New York.
FAR TO CLOSE FOR COM FORT
LAGUNA BEACH MAN KILLED IN TRENCH CAVE -INA 50 year old community activist died after the walls of a 12-foot trench collapsed while he was trying to install electrical wiring on his property. He was buried under six feet of earth when the sides of the unshored trench caved in. "He was conscious and talking at one point" said a Laguna Beach fire captain. "He may have been yelling, but we could barely hear him through the dirt. Then, there was a sound of panic and we didn't hear from him after that." A second man was buried to his waist by the cave-in, but managed to dig himself out after firefighters threw him a shovel.
The survivor said "All day he had been asking me, 'If this caves in, where are you gonna go?' I asked him this morning, let's get some boards to shore this thing up and he said, 'We're almost done.' In five more minutes we would have been sitting at the table eating lunch." It took firefighters an hour to reach the man's wrist and determine he was dead. It took them another five hours to pull his body from the trench.
Other stories and accounts of trench cave-ins may be found at www.trenchsafety.org/trench/sample/archives
WHY DO CAVE-INS OCCUR?Undisturbed soil is kept in place by natural horizontal and vertical forces of the nearby soil as well as cohesive properties of some soils. When we dig in the earth, these natural forces are no longer able to hold back the soil left behind. With no support, eventually the laws of gravity take over, and the soil from the excavation walls move downward and inward into the excavation. The result is a cave-in.
Cave-ins are more likely to occur in unprotected excavations where:
The excavation is dug in unstable soil, or in soil that has been dug in before;
There is excessive vibration from construction equipment or vehicle traffic around the excavation ;
Too much weight near the sides of an excavation, most frequently from equipment or the excavated material (spoil pile) too near to the edge;
Water has collected in the excavation;
Changes in weather conditions (freezing, melting, sudden heavy rain, etc.)
OTHER CAUSES OF DEATHS
Misinterpreting trench stability, soil conditions, slope or using improper trench protection methods
DISTURBING STATISTICSTrench fatalities are a serious problem in construction. According to the Occupational Safety and Health Administration (OSHA), in 2003, were killed in trenching and excavation mishaps. This compares to. Indeed, since 1990, trench fatalities had never exceeded 43 in any given year. After the spike in 2003, OSHA investigated of the deaths and reported its key findings. Trench fatalities are a serious problem in construction. According to the Occupational Safety and Health Administration (OSHA), in 2003, workers were killed in trenching and excavation mishaps. This compares to. Indeed, since 1990, trench fatalities had never exceeded in any given year. After the spike in 2003, OSHA investigated of the deaths and reported its key findings.
In the investigated fatalities, protective systems were found to be properly employed in only 24 percent of the trenches. In the remainder, a protective system was either improperly used (24%), available but not in use (12%) or simply unavailable (64%).
Further, despite the fact that environmental conditions were a contributing factor in of the fatalities, the competent person was not onsite when the fatality occurred of the time. Most of the time the employer had not identified the soil type even though soil type is a factor in trench cave-ins.
The OSHA investigations showed that schedule time was more important than safety in of the incidents. "It happens all the time," says Schneider. "It's a shallow trench, not too long. Everyone there wants to keep moving, and they don't take the time to ensure protection."
In 2003, of the fatalities occurred in trenches less than nine feet deep. Only nine percent occurred deeper than 15 feet.
The most commonly killed employees were construction laborers with plumbers and pipe fitters following next at nine percent. Most were killed while installing pipe.
Fifty-six percent of these fatalities were Hispanics, and were foreign-born.
For Spanish was their primary language. At least 30 percent had been working for their employer for less than a year, and most worked for a subcontractor.
Construction is one of the most hazardous industries. Each year a substantial number of construction workers lost their lives; many others are injured. OSHA estimates of the number of fatalities range from several hundred to over 2,000 per year. (OSHA, 1990). During 2000, construction again recorded the highest number of fatal work injuries of any industry with 1,154 fatalities reported. Although the total for the industry was down about 3% - the first decline for construction since 1996, if compared with 1999. (BLS, 2001).
Trenching fatalities continue to plague the construction industry. While accurate records of the actual number of fatalities occurring in trenching incidents are not maintained, the estimate of 100 fatalities per year is perhaps a reasonable approximation of the magnitude of the problem.
According to an analysis by the National Institute for Occupational Safety and Health (NIOSH) of worker‘s compensation claims in the Supplementary Data System of the Bureau of Labor Statistics, there are approximately 1000 work related injuries each year due to excavation cave-ins. Of these, about 140 result in permanent disability and 75 in death.
Excavations and Trenching OSHA Requirements for Excavations and Trenching Excavation and trenching are among the most hazardous construction operations. The Occupational Safety and Health Administration's (OSHA) Excavation and Trenching standard,, Part 1926.650, covers requirements for excavation and trenching operations. There is a booklet titled ―Excavations‖, OSHA 2226 2002 (Revised). This booklet highlights key elements of the standard, shows ways to protect employees against cave-ins, and describes safe work practices for employees. A copy can be viewed on the OSHA web site at http://www.osha.gov/Publications/OSHA2226/2226.html Definitions of Excavation and Trenching OSHA defines an as man-made cut, cavity, trench, or depression in the earth‘s surface as formed by earth removal. This can include anything from excavations for home foundations to a new highway.
A refers to a narrow excavation made below the surface of the ground in which the depth is greater than the width-and the width Trenching is common in construction and utility work, where underground piping or cables are being installed or repaired.
If an excavation is more than 5 feet in depth, there must be a in place while workers are in the excavation.
THE KEY TO PROTECTING YOURSELFA. Knowing the hazards you and your co-workers face while working in trenches and excavations B. Protecting yourself by using common sense, following established safe work practices and adhering to accepted safety standards C. Avoid taking risks!
There should be no excuse for an injury resulting from a cave-in, as cave-ins are both predicable and preventable!
Preplanning Pre-job or project planning is an extremely important aspect of a safe trenching and excavation project. This is where many incidents can be avoided well before any soil is excavated.
The competent person must take an active role in the process.
Important tasks & considerations would include:
Surface Encumbrance Assessment – Surface encumbrances are essentially any object or structure which could pose a hazard during the project. Prior to beginning any project, all potential surface encumbrances must be identified and addressed to ensure safety.
Examples of surface encumbrances can include but are not limited to:
Note: adjacent utilities must be located, removed or supported to protect employees from potential injury.
Utility Locations – All underground utilities must be located to determine their approximate location.
Remember, locators dispatched by utility companies can only provide approximate locations of their lines and systems.
By law, Under Ground Service Alert, Dig Alert or any other underground utility locating service must be contacted at least two working days prior to excavation. Emergency repair is generally exempted, but every effort must be made to safely locate underground utilities.
Many states have specific training requirements for employees involved in utility location. Be sure any employees involved in this activity are properly trained for the activity. Also be sure that any location services have properly trained personnel as well.
Once the approximate location of utilities has been determined, the actual location must be accomplished by carefully digging with hand tools. Avoid using metal handled tools as they can provide a direct link for electrocution. Wood or fiber glass handled tools are generally a good choice. If there is an electrical hazard, it's a good idea to use lineman's gloves for extra protection.
Never use backhoes, breakers, digging bars or other metal tools to locate or work around utilities due to the electrocution and spark hazard potential.
While the trench or excavation is being opened, utilities must be protected or supported or removed to prevent injury to workers should a pole or other object happen to fall.
Access and Egress Ladders, ramps and stairways must be provided in all excavations 4 feet or more in depth.
Secured ladders must be placed every 25 feet of lateral travel. In addition, ladders must extend at least 2-3 feet above the top of the excavation. Employees must never be allowed to climb in and out of the trench by means of the shoring system.
Again be very careful as the type and condition of the ladder you choose to use. Due to electrical hazards metallic ladders must be avoided, good choices are fiberglass or wood ladders maintained in good condition.
Hand made construction ladders must conform to CAL/OSHA Article 25 Section 1676 "JOBMADE LADDERS". Be sure that the ladder is safely secured to a stationary object to prevent the ladder from tipping or slipping during use.
Where employees are permitted to cross an excavation, a walkway constructed with standard 42" guard rails must be provided.
Open Trenches Shafts, pits, wells etc, must be barricaded or covered when not in use and back filled when the job is complete. In cases where employees may fall into the excavation, a protection system must be employed.
This is especially important to also protect the public and children from an accidental fall.
Traffic Control Employees exposed to vehicular or construction traffic must wear orange vests. If the lighting is poor or work is performed at night, reflectorized vests would be required as well as appropriate lighting in order to work safely.
Flagging Operations Employees used for flagging operations must be specifically trained for that activity. A person should be chosen to be a flagger because the supervisor feels the person is physically able, mentally alert, and sufficiently commanding in appearance to properly control traffic through construction, maintenance, and utility work areas.
A flagger‘s chief duties are to guide traffic safely through work areas, protect fellow workers, prevent unreasonable delays for road users, and answer motorists‘ questions politely and knowledgeably.
Manufacturer’s Tabulated Data Any shoring material/equipment that is to be used on site must be accompanied with current manufacturers‘ tabulated data. Should an OSHA official ask to see the documentation; a citation will be issued if it is not readily available.
Training Training Components Many of the specific examples used in this manual came from material for UC Irvine. The company or contractor must coordinate all trenching and shoring training and provide a training program that will teach employees, who might be exposed to Trenching and Shoring hazards, how to recognize such hazards and how to minimize them.
Employees should be trained in the following areas:
(a) The nature of Trenching and Shoring hazards in the work area;
(b) The correct procedures for erecting, maintaining, disassembling, and inspecting Trenching and Shoring protection systems;
(c) The use and operation of Trenching and Shoring equipment (d) The role of each employee in the Trenching and Shoring safety monitoring system when the system is in use;