RECOGNIZING AND PREVENTING CONSTRUCTION HAZARDS

The first step necessary for reducing accidents, injuries, and occupational diseases in construction is to establish an on the job program of hazard recognition and prevention.

This action is effective for identifying and abating construction hazards involving falls, struck-by, getting caught, and electrocutions. This chapter discusses approaches for developing such a program on construction operations.

What’s A Useful Approach For Recognizing Hazards On Construction Projects?
It’s useful for construction workers to have a quick and easy way to identify hazards on the job. The following hazard recognition program can help do this. Using this method, the next sections describe the previously cited four major hazard areas. Examples are provided for each area, along with actual cases of occupational accidents, injuries, and deaths that have resulted when proper practices and
safeguards were not implemented. Through a hazard recognition program, workers and supervisors can survey their work environment and operation for both general and specific hazards that exist or could develop, and then take the necessary actions for protection.

1. Fall Hazards — There are two types of fall hazards: falls from a higher to a lower level, and falls on the same level.

Examples and actual cases involving these hazards include:
a. locations where fixed as well as movable ladders are being used;
b. fall hazards resulting from poor housekeeping practices, spilled fluids, lack of proper guardrails, lifelines, safety nets, and safety belts; unguarded openings in floors, trenches, and other construction work areas;
d. scaffolds and elevated platforms improperly erected, guarded, inspected, and/or maintained;
e. loose fitting clothing or inadequate work shoes or boots which can cause a worker to trip;
f. slippery work surfaces;
g. situation where a worker can fall when trying to move a large awkward object on an elevated work area.

Actual cases:
a. “Carpenters were setting trusses on the second floor of a house they were building. There was no
guardrail or floor cover over the floor opening for the stairway. While placing a truss in position, one
of the carpenters fell through the opening to the concrete basement below.”

b. “A crew laying bricks on the upper floor of a three-story building built a six-foot platform spanning a gap between two scaffolds. The platform was correctly constructed of two 2" × 12" planks with standard guardrails; however, one of the planks was not scaffold grade lumber and also had extensive dry rot in the center. When a bricklayer stepped on the plank it disintegrated and he
fell 30 feet to his death.”

c. “A laborer was working on the third level of a tubular welded frame scaffold which was covered
with ice and snow. Planking on the scaffold was inadequate, there was no guardrail and no access ladder for the various scaffold levels. The worker slipped and fell head first approximately 20 feet to the pavement below."

2. Struck-by Hazards — These hazards occur where employees can be struck by objects, materials, equipment and/or vehicles. Often these types of hazards result from unsafe work practices, poor planning, or lack of training. The following are examples and actual cases pertaining to these hazards:

Examples:
a. improperly guarded equipment, machinery, power tools or instruments;
b. materials or equipment improperly stored or handled overhead;
c. lifting, pulling, pushing, or carrying materials and/or equipment;
d. work on or near conveyors, belts, hoists, and rollers used for moving stock/material;
e. material loading, unloading, storage, and sorting;
f. work with hand carts, power equipment, hand tools, gas cylinders, and cranes;
g. exposure to passing vehicles.

Actual cases:
a. “Four employees were working near pile driving equipment preparing to drive the first piling. Apparently the two clips on the eye of the hammer hoisting rope slipped, permitting the hammer which was still inside the lead to fall some 45 feet. The hammer struck a large timber on the ground breaking it. One end of the timber struck the employees, fatally injuring one man.”

b. “Two employees were doing remodeling construction and were building a wall. One of the workers was killed when he was struck by a nail fired from a powder-actuated tool. The tool operator, while attempting to anchor plywood to a 2" × 4" stud, fired the tool. The nail penetrated the stud and the plywood partition prior to striking the victim.”

c. “An employee was in the process of locating an underground water line. A trench had been dug approximately 4 feet deep along side a brick wall 7 feet high and 5 feet long. The brick wall collapsed onto the victim who was standing in the trench. The injuries were fatal.”

3. Getting Caught Hazards — The three common types of hazards found in this category include caught in, caught on, and caught between. Examples and actual cases are:
Examples:
a. working surfaces and equipment where an employee can catch a limb in an unguarded opening;
b. workplaces or sites where a worker can get “caught in” a cave-in, or a confined space;
c. any fixed or moving projections pose a threat to workers in the form of “caught on” hazards, such as when a worker gets his or her hair, limb, or article of clothing caught on a moving part and dragged into a machine;
d. employees confront “caught between” hazards resulting from operations where two objects move toward each other, or one object moves toward a stationary one;
e. conveyor belts, excavations, fuel tanks and other confined spaces, as well as moving vehicles of any kind may present a caught in, caught on, or caught between hazard.

Actual cases:
a. “Construction workers were installing new fittings to the gang-edger waste conveyor. To move their equipment over the conveyor they placed a steel plate on top of it. A worker crossing over the conveyor fell into it, trapping his leg in the box link chain. The conveyor carried him forward, wedging his right leg under the steel plate. He suffered massive crush injuries to his leg.”

b. “The operator was exiting a rubber-tired front loader with the bucket still in the raised position, when his rain jacket caught on the arm-control lever. The snagged jacket caused him to slip, activating the bucket-arm control. He was trapped on the frame when the bucket dropped. He suffered serious injuries when crushed between the boom arms and the machine frame.”

c. “A driller/blaster was waiting in his rock drill cab for a call to move further up the road being constructed. He put the drill in rotation and left the cab to grease the hammer and centralizer on the drilling arm. He greased the fittings on one side of the hammer and walked around the 10 foot rotating drill steel and somehow caught his clothes on the end of the steel. He was found lying close to the drill steel end, the clothes torn from his upper body.”

4. Electrocution Hazards — As one of the primary causes of death in the construction industry, these hazards deserve careful attention for hazard recognition. While workers are likely to be aware of overhead power lines, as the following examples and cases reveal, there are power line contact dangers that can be quite unexpected. Construction workers need to have specialized knowledge in this area, such as the minimum distance requirement for live-line work, and principles of arc generation. Many electrical accidents are not the result of a worker’s direct contact with a power line. Often, these accidents are from indirect contact.

For example, while using equipment or machinery, a worker may become distracted from touching a live wire with one of these objects. This can occur especially with a ladder or a moving vehicle.

General Examples: Electrical hazards that can occur in both in-plant and outdoor construction projects include:
a. Lack of Ground Fault Current Interrupter;
b. Contact with power lines;
c. Path to ground missing or discontinuous;
d. Equipment not used in manner prescribed;
e. Improper and unsafe electrical installation.

Actual Cases:
a. “Two employees were installing aluminum siding on a farmhouse when it became necessary to remove a 36-foot high metal pole CB antenna. One employee stood on a metal pick board between two ladders and unfastened the antenna at the top of the house. The other employee, who was standing on the ground, took the antenna to lay it down in the yard. The antenna made electrical contact with a 7200-volt power transmission line 30 feet 10 inches from the house and 23 feet 9 inches above the ground. The employee handling the antenna received a fatal shock and the other employee a minor shock.”

b. “Employees were moving a steel canopy structure using a “boom crane” truck. The boom cable made contact with a 7200 volt electrical power distribution line electrocuting the operator of the crane; he was the foreman at the site,” [who stepped in to operate the crane].

c. “A lineman was electrocuted while working on grounded de-energized lines. He was working from a defective basket on an articulated boom aerial lift when the basket contacted energized lines which ran beneath the de-energized lines. The defective basket permitted current to pass through a drain hole cut into the body of the basket, then through the employee, and to ground via the de-energized line.”