Worker Safety Series

1. Construction
2. Nearly 6.5 million people work at approximately 252,000 construction sites across the nation on any given day. The fatal injury rate for the construction industry is higher than the national average in this category for all industries.
3. Potential hazards for workers in construction include:

1. Falls (from heights)       
2. Trench collapse;
3. Scaffold collapse;
4. Electric shock and arc flash/arc blast;
5. Failure to use proper personal protective equipment; and
6. Repetitive motion injuries.
7. 
   
8. Hazards & Solutions
9. For construction, the 10 OSHA standards most frequently included in the agency's citations in FY 2004 were:
10. Scaffolding
11. Fall protection (scope, application, definitions)
12. Excavations (general requirements)
13. Ladders
14. Head protection
15. Excavations (requirements for protective systems)
16. Hazard communication
17. Fall protection (training requirements)
18. Construction (general safety and health provisions)
19. Electrical (wiring methods, design and protection)
20. 
    
21. Scaffolding
22. Hazard: When scaffolds are not erected or used properly, fall hazards can occur. About 2.3 million construction workers frequently work on scaffolds. Protecting these workers from scaffold-related accidents would prevent an estimated 4,500 injuries and 50 fatalities each year.
23. Solutions:

1. Scaffold must be sound, rigid and sufficient to carry its own weight plus four times the maximum intended load without settling or displacement. It must be erected on solid footing.
2. Unstable objects, such as barrels, boxes, loose bricks or concrete blocks must not be used to support scaffolds or planks.
3. Scaffold must not be erected, moved, dismantled or altered except under the supervision of a competent person.
4. Scaffold must be equipped with guardrails, midrails and toeboards.
5. Scaffold accessories such as braces, brackets, trusses, screw legs or ladders that are damaged or weakened from any cause must be immediately repaired or replaced.
6. Scaffold platforms must be tightly planked with scaffold plank grade material or equivalent.
7. A "competent person" must inspect the scaffolding and, at designated intervals, reinspect it.
8. Rigging on suspension scaffolds must be inspected by a competent person before each shift and after any occurrence that could affect structural integrity to ensure that all connections are tight and that no damage to the rigging has occurred since its last use.
9. Synthetic and natural rope used in suspension scaffolding must be protected from heat-producing sources.
10. Employees must be instructed about the hazards of using diagonal braces as fall protection.
11. Scaffold can be accessed by using ladders and stairwells.
12. Scaffolds must be at least 10 feet from electric power lines at all times.
13. Fall Protection
14. Hazard: Each year, falls consistently account for the greatest number of fatalities in the construction industry. A number of factors are often involved in falls, including unstable working surfaces, misuse or failure to use fall protection equipment and human error. Studies have shown that using guardrails, fall arrest systems, safety nets, covers and restraint systems can prevent many deaths and injuries from falls.
15. Solutions:

1. Consider using aerial lifts or elevated platforms to provide safer elevated working surfaces;
2. Erect guardrail systems with toeboards and warning lines or install control line systems to protect workers near the edges of floors and roofs;
3. Cover floor holes; and/or
4. Use safety net systems or personal fall arrest systems (body harnesses).
5. Ladders
6. Hazard: Ladders and stairways are another source of injuries and fatalities among construction workers. OSHA estimates that there are 24,882 injuries and as many as 36 fatalities per year due to falls on stairways and ladders used in construction. Nearly half of these injuries were serious enough to require time off the job.
7. Solutions:

1. Use the correct ladder for the task.
2. Have a competent person visually inspect a ladder before use for any defects such as:
1. Structural damage, split/bent side rails, broken or missing rungs/steps/cleats and missing or damaged safety devices;
2. Grease, dirt or other contaminants that could cause slips or falls;
3. Paint or stickers (except warning labels) that could hide possible defects
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3. Make sure that ladders are long enough to safely reach the work area.
4. Mark or tag ("Do Not Use") damaged or defective ladders for repair or replacement, or destroy them immediately.
5. Never load ladders beyond the maximum intended load or beyond the manufacturer's rated capacity.
6. Be sure the load rating can support the weight of the user, including materials and tools.
7. Avoid using ladders with metallic components near electrical work and overhead power lines.
8. Stairways
9. Hazard: Slips, trips and falls on stairways are a major source of injuries and fatalities among construction workers.
10. Solutions:

1. Stairway treads and walkways must be free of dangerous objects, debris and materials.
2. Slippery conditions on stairways and walkways must be corrected immediately.
3. Make sure that treads cover the entire step and landing.
4. Stairways having four or more risers or rising more than 30 inches must have at least one handrail.

5. Head Protection

   Hazard: Serious head injuries can result from blows to the head.

   Solution:

   • Be sure that workers wear hard hats where there is a potential for objects falling from above, bumps to their heads from fixed objects, or accidental head contact with electrical hazards.

   
   

   Safety Checklists

   The following checklists may help you take steps to avoid hazards that cause injuries, illnesses and fatalities. As always, be cautious and seek help if you are concerned about a potential hazard.

   Personal Protective Equipment (PPE)

   Eye and Face Protection

   • Safety glasses or face shields are worn anytime work operations can cause foreign objects getting into the eye such as during welding, cutting, grinding, nailing (or when working with concrete and/or harmful chemicals or when exposed to flying particles).
   • Eye and face protectors are selected based on anticipated hazards.
   • Safety glasses or face shields are worn when exposed to any electrical hazards including work on energized electrical systems.
   Foot Protection
   • Construction workers should wear work shoes or boots with slip-resistant and puncture-resistant soles.
   • Safety-toed footwear is worn to prevent crushed toes when working around heavy equipment or falling objects.

   Hand Protection

   • Gloves should fit snugly.
   • Workers wear the right gloves for the job (for example, heavy-duty rubber gloves for concrete work, welding gloves for welding, insulated gloves and sleeves when exposed to electrical hazards).

   Head Protection

   • Workers shall wear hard hats where there is a potential for objects falling from above, bumps to their heads from fixed objects, or of accidental head contact with electrical hazards.
   • Hard hats are routinely inspected for dents, cracks or deterioration.
   • Hard hats are replaced after a heavy blow or electrical shock.
   • Hard hats are maintained in good condition.

   Scaffolding

   • Scaffolds should be set on sound footing.
   • Damaged parts that affect the strength of the scaffold are taken out of service.
   • Scaffolds are not altered.
   • All scaffolds should be fully planked.
   • Scaffolds are not moved horizontally while workers are on them unless they are designed to be mobile and workers have been trained in the proper procedures.
   • Employees are not permitted to work on scaffolds when covered with snow, ice, or other slippery materials.
   • Scaffolds are not erected or moved within 10 feet of power lines.
   • Employees are not permitted to work on scaffolds in bad weather or high winds unless a competent person has determined that it is safe to do so.
   • Ladders, boxes, barrels, buckets or other makeshift platforms are not used to raise work height.
   • Extra material is not allowed to build up on scaffold platforms.
   • Scaffolds should not be loaded with more weight than they were designed to support.

   Electrical Safety

   • Work on new and existing energized (hot) electrical circuits is prohibited until all power is shut off and grounds are attached.
   • An effective Lockout/Tagout system is in place.
   • Frayed, damaged or worn electrical cords or cables are promptly replaced.
   • All extension cords have grounding prongs.
   • Protect flexible cords and cables from damage. Sharp corners and projections should be avoided.
   • Use extension cord sets used with portable electric tools and appliances that are the three-wire type and designed for hard or extra-hard service. (Look for some of the following letters imprinted on the casing: S, ST, SO, STO.)
   • All electrical tools and equipment are maintained in safe condition and checked regularly for defects and taken out of service if a defect is found.
   • Do not bypass any protective system or device designed to protect employees from contact with electrical energy.
   • Overhead electrical power lines are located and identified.
   • Ensure that ladders, scaffolds, equipment or materials never come within 10 feet of electrical power lines.
   • All electrical tools must be properly grounded unless they are of the double insulated type.
   • Multiple plug adapters are prohibited.
   Floor and Wall Openings
   • Floor openings (12 inches or more) are guarded by a secured cover, a guardrail or equivalent on all sides (except at entrances to stairways).
   • Toeboards are installed around the edges of permanent floor openings (where persons may pass below the opening).

   Elevated Surfaces

   • Signs are posted, when appropriate, showing the elevated surface load capacity.
   • Surfaces elevated more than 48 inches above the floor or ground have standard guardrails.
   • All elevated surfaces (beneath which people or machinery could be exposed to falling objects) have standard 4-inch toeboards.
   • A permanent means of entry and exit with handrails is provided to elevated storage and work surfaces.
   • Material is piled, stacked or racked in a way that prevents it from tipping, falling, collapsing, rolling or spreading.

   Hazard Communication

   • A list of hazardous substances used in the workplace is maintained and readily available at the worksite.
   • There is a written hazard communication program addressing Material Safety Data Sheets (MSDS), labeling and employee training.
   • Each container of a hazardous substance (vats, bottles, storage tanks) is labeled with product identity and a hazard warning(s) (communicating the specific health hazards and physical hazards).
   • Material Safety Data Sheets are readily available at all times for each hazardous substance used.
   • There is an effective employee training program for hazardous substances.

   Crane Safety

   • Cranes and derricks are restricted from operating within 10 feet of any electrical power line.
   • The upper rotating structure supporting the boom and materials being handled is provided with an electrical ground while working near energized transmitter towers.
   • Rated load capacities, operating speed and instructions are posted and visible to the operator.
   • Cranes are equipped with a load chart.
   • The operator understands and uses the load chart.
   • The operator can determine the angle and length of the crane boom at all times.
   • Crane machinery and other rigging equipment is inspected daily prior to use to make sure that it is in good condition.
   • Accessible areas within the crane's swing radius are barricaded.
   • Tag lines are used to prevent dangerous swing or spin of materials when raised or lowered by a crane or derrick.
   • Illustrations of hand signals to crane and derrick operators are posted on the job site.
   • The signal person uses correct signals for the crane operator to follow.
   • Crane outriggers are extended when required.
   • Crane platforms and walkways have antiskid surfaces.
   • Broken, worn or damaged wire rope is removed from service.
   • Guardrails, hand holds and steps are provided for safe and easy access to and from all areas of the crane.
   • Load testing reports/certifications are available.
   • Tower crane mast bolts are properly torqued to the manufacturer's specifications.
   • Overload limits are tested and correctly set.
   • The maximum acceptable load and the last test results are posted on the crane.
   • Initial and annual inspections of all hoisting and rigging equipment are performed and reports are maintained.
   • Only properly trained and qualified operators are allowed to work with hoisting and rigging equipment.

   Forklifts

   • Forklift truck operators are competent to operate these vehicles safely as demonstrated by their successful completion of training and evaluation.
   • No employee under 18 years old is allowed to operate a forklift.
   • Forklifts are inspected daily for proper condition of brakes, horns, steering, forks and tires.
   • Powered industrial trucks (forklifts) meet the design and construction requirements established in American National Standards Institute (ANSI) for Powered Industrial Trucks, Part II ANSI B56.1-1969.
   • Written approval from the truck manufacturer is obtained for any modification or additions which affect capacity and safe operation of the vehicle.
   • Capacity, operation and maintenance instruction plates, tags or decals are changed to indicate any modifications or additions to the vehicle.
   • Battery charging is conducted in areas specifically designated for that purpose.
   • Material handling equipment is provided for handling batteries, including conveyors, overhead hoists or equivalent devices.
   • Reinstalled batteries are properly positioned and secured in the truck.
   • Smoking is prohibited in battery charging areas.
   • Precautions are taken to prevent open flames, sparks or electric arcs in battery charging areas.
   • Refresher training is provided and an evaluation is conducted whenever a forklift operator has been observed operating the vehicle in an unsafe manner and when an operator is assigned to drive a different type of truck.
   • Load and forks are fully lowered, controls neutralized, power shut off and brakes set when a powered industrial truck is left unattended.
   • There is sufficient headroom for the forklift and operator under overhead installations, lights, pipes, sprinkler systems, etc.
   • Overhead guards are in place to protect the operator against falling objects.
   • Trucks are operated at a safe speed.
   • All loads are kept stable, safely arranged and fit within the rated capacity of the truck.
   • Unsafe and defective trucks are removed from service.

Duties of civil engineers

Civil engineers typically do the following:

• Analyze survey reports, maps, and other data to plan projects
• Consider construction costs, government regulations, potential environmental hazards, and other factors in planning stages and risk analysis
• Compile and submit permit applications to local, state, and federal agencies verifying that projects comply with various regulations
• Perform or oversee soil testing to determine the adequacy and strength of foundations
• Test building materials, such as concrete, asphalt, or steel, for use in particular projects
• Provide cost estimates for materials, equipment, or labor to determine a project's economic feasibility
• Use design software to plan and design transportation systems, hydraulic systems, and structures in line with industry and government standards
• Perform or oversee, surveying operations to establish reference points, grades, and elevations to guide construction
• Present their findings to the public on topics such as bid proposals, environmental impact statements, or property descriptions
• Manage the repair, maintenance, and replacement of public and private infrastructure

Many civil engineers hold supervisory or administrative positions ranging from supervisor of a construction site to city engineer. Others work in design, construction, research, and teaching. Civil engineers work with others on projects and may be assisted by civil engineering technician.

The federal government employs civil engineers to do many of the same things done in private industry, except that the federally employed civil engineers may also inspect projects to be sure that they comply with regulations.

Civil engineers work on complex projects, so they usually specialize in one of several areas.

Construction engineers manage construction projects, ensuring that they are scheduled and built in accordance with the plans and specifications. They are typically responsible for design and safety of temporary structures used during construction.

Geotechnical engineers work to make sure that foundations are solid. They focus on how structures built by civil engineers, such as buildings and tunnels, interact with the earth (including soil and rock). In addition, they design and plan for slopes, retaining walls, and tunnels.

Structural engineers design and assess major projects, such as buildings, bridges, or dams, to ensure their strength and durability.

Transportation engineers plan, design, operate, and maintain everyday systems, such as streets and highways, but they also plan larger projects, such as airports, ports, mass transit systems, and harbors.

EIFFEL TOWER

The Eiffel Tower  is an iron lattice tower located on the Champ de Mars inParis, France. It was named after the engineer Alexandre Gustave Eiffel, whose company designed and built the tower. Erected in 1889 as the entrance arch to the 1889 World Fair, it was initially criticised by some of France's leading artists and intellectuals for its design, but has become both a global cultural icon of France and one of the most recognizable structures in the world. The tower is the tallest structure in paris and the most-visited paid monument in the world; 6.98 million people ascended it in 2011. The tower received its 250 millionth visitor in 2010.

The tower is 324 metres (1,063 ft) tall,  about the same height as an 81-storey building. Its base is square, 125 metres (410 ft) on a side. During its construction, the Eiffel Tower surpassed the Washington Monument to assume the title of the tallest man-made structure in the world, a title it held for 41 years, until the Chrysler Building in New York City was built in 1930. Because of the addition of the aerial atop the Eiffel Tower in 1957, it is now taller than the Chrysler Building by 5.2 metres (17 ft). Not includingbroadcast aerials, it is the second-tallest structure in France, after the Millau Viaduct.

The tower has three levels for visitors, with restaurants on the first and second. The third level observatory's upper platform is 276 m (906 ft) above the ground,  the highest accessible to the public in the European Union. Tickets can be purchased to ascend bystairs or lift (elevator) to the first and second levels. The climb from ground level to the first level is over 300 steps, as is the walk from the first to the second level. Although there are stairs to the third and highest level, these are usually closed to the public and it is generally only accessible by lift.

The design of the Eiffel Tower was originated by Maurice Koechlin and Émile Nouguier, two senior engineers who worked for theCompagnie des Établissements Eiffel, after discussion about a suitable centrepiece for the proposed 1889 Exposition Universelle, aWorld's Fair which would celebrate the centennial of the French Revolution. In May 1884 Koechlin, working at home, made an outline drawing of their scheme, described by him as "a great pylon, consisting of four lattice girders standing apart at the base and coming together at the top, joined together by metal trusses at regular intervals". Initially Eiffel himself showed little enthusiasm, but he did sanction further study of the project, and the two engineers then asked Stephen Sauvestre, the head of company's architectural department, to contribute to the design. Sauvestre added decorative arches to the base, a glass pavilion to the first level, and other embellishments. This enhanced version gained Eiffel's support: he bought the rights to the patent on the design which Koechlin, Nougier, and Sauvestre had taken out, and the design was exhibited at the Exhibition of Decorative Arts in the autumn of 1884 under the company name. On 30 March 1885 Eiffel presented a paper on the project to the Société des Ingénieurs Civils; after discussing the technical problems and emphasising the practical uses of the tower, he finished his talk by saying that the tower would symbolise

Little happened until the beginning of 1886, when Jules Grévy was re-elected as President and Édouard Lockroy was appointed as Minister for Trade. A budget for the Exposition was passed and on 1 May Lockroy announced an alteration to the terms of the open competition which was being held for a centerpiece for the exposition, which effectively made the choice of Eiffel's design a foregone conclusion: all entries had to include a study for a 300 m (980 ft) four-sided metal tower on the Champ de Mars. On 12 May a commission was set up to examine Eiffel's scheme and its rivals and on 12 June it presented its decision, which was that all the proposals except Eiffel's were either impractical or insufficiently worked out. After some debate about the exact site for the tower, a contract was finally signed on 8 January 1887. This was signed by Eiffel acting in his own capacity rather than as the representative of his company, and granted him 1.5 million francs toward the construction costs: less than a quarter of the estimated 6.5 million francs. Eiffel was to receive all income from the commercial exploitation of the tower during the exhibition and for the following twenty years. Eiffel later established a separate company to manage the tower, putting up half the necessary capital himself.

Work on the foundations started on 28 January 1887. Those for the east and south legs were straightforward, each leg resting on four 2 m (6.6 ft) concrete slabs, one for each of the principal girders of each leg but the other two, being closer to the river Seine, were more complicated: each slab needed two piles installed by using compressed-air caissons 15 m (49 ft) long and 6 m (20 ft) in diameter driven to a depth of 22 m (72 ft) to support the concrete slabs, which were 6 m (20 ft) thick. Each of these slabs supported a block built oflimestone each with an inclined top to bear a supporting shoe for the ironwork.

Each shoe was anchored into the stonework by a pair of bolts 10 cm (4 in) in diameter and 7.5 m (25 ft) long. The foundations were complete by 30 June and the erection of the ironwork began. The very visible work on-site was complemented by the enormous amount of exacting preparatory work that was entailed: the drawing office produced 1,700 general drawings and 3,629 detailed drawings of the 18,038 different parts needed. The task of drawing the components was complicated by the complex angles involved in the design and the degree of precision required: the position of rivet holes was specified to within 0.1 mm (0.004 in) and angles worked out to onesecond of arc. The finished components, some already riveted together into sub-assemblies, arrived on horse-drawn carts from the factory in the nearby Parisian suburb of Levallois-Perret and were first bolted together, the bolts being replaced by rivets as construction progressed. No drilling or shaping was done on site: if any part did not fit it was sent back to the factory for alteration. In all there were 18,038 pieces joined by two and a half million rivets.

At first the legs were constructed as cantilevers but about halfway to the first level construction was paused in order to construct a substantial timber scaffold. This caused a renewal of the concerns about the structural soundness of the project, and sensational headlines such as "Eiffel Suicide!" and "Gustave Eiffel has gone mad: he has been confined in an Asylum" appeared in the popular press.At this stage a small "creeper" crane was installed in each leg, designed to move up the tower as construction progressed and making use of the guides for the lifts which were to be fitted in each leg. The critical stage of joining the four legs at the first level was complete by the end of March 1888. Although the metalwork had been prepared with the utmost precision, provision had been made to carry out small adjustments in order to precisely align the legs: hydraulic jacks were fitted to the shoes at the base of each leg, each capable of exerting a force of 800 tonnes, and in addition the legs had been intentionally constructed at a slightly steeper angle than necessary, being supported by sandboxeson the scaffold. Although construction involved 300 on-site employees, only one person died thanks to Eiffel's stringent safety precautions and use of movable stagings, guard-rails, and screens.