Building the Golden Gate Bridge
Needlestick Injuries
Tractor Rollovers
Couplers, Brakes, and Trainmen
Building the Golden Gate Bridge
The Golden Gate bridge, which links San Francisco and Marin County, has been designated by the American Society of Engineers as one of the 7 civil engineering wonders of the world. When it opened in 1937, it had the longest main span of any suspension bridge in existence.
The bridge was built in 4 years. Construction was difficult and dangerous. The Golden Gate Strait is swept by strong winds, fierce ocean currents, and is often shrouded in thick fog. The bridge required the tallest towers, the longest and thickest cables, and the largest underwater foundation piers that had ever been built. The piers had to be sunk in violent open sea waters, which many thought impossible.
The bridge opened ahead of schedule and under budget--$35 million dollars. At the time, the norm was that a worker was killed for every million dollars spent, and given the inherent dangers and speed of the task, more than 35 fatalities could have been expected.
But the chief engineer, Joseph B. Strauss, insisted on the use of the most rigorous safety precautions ever used in bridge construction. Probably the most important was the "no nonsense rule"; anyone working on the bridge caught stunting, showing off, or behaving dangerously was immediately fired. Strauss also required that protective headgear, a prototype of the modern day hard hat, be worn, as well as glare-free goggles. Special face and hand cream protected workers against the wind. Men who had to climb to great heights were put on special diets to prevent dizziness.
The most conspicuous precaution was the safety net, suspended under the bridge floor, from end to end. During construction, the net saved the lives of nineteen workers who accidentally fell from the bridge. These men became known as the "Halfway to Hell Club." By contrast, twenty-eight workers had fallen off the recently completed San Francisco Bay Bridge, and all had died.
In the first three years of construction, only one man died, setting a record low for bridge fatalities. Unfortunately, on February 17, 1937, an additional ten men lost their lives when a section of the scaffold fell and broke through the safety net. Still, eleven fatalities on such a project was a safety triumph.
Ironically, through the years, the Golden Gate bridge has become the number one site for suicides-people jumping from the bridge. Suicide professionals advocate not the replacement of the safety net, but a suicide barrier (e.g. fence), similar to ones that have virtually eliminated suicides from the Eiffel Tower and the Empire State building. Clinical experience, and a great deal of research evidence, indicate that people stopped from jumping off the Golden Gate bridge will rarely go on to kill themselves in other ways.
Moral: It is possible to make even the most dangerous workplaces relatively safe.
Sources:
Adams CF. Heroes of the Golden Gate. Palo Alto: Pacific Books. 1987.
Van Der Zee, J. The Gate: The True Story of the Design and Construction of the Golden Gate Bridge. New York: Simon & Schuster. 1986.
Currie MC, Moore TJ. Golden Gate Bridge. http://products.engineering.com/community/engineering/engmarvel/goldengate.htm. Accessed October 2005.
Wonders of the World: Golden Gate Bridge. http://www.pbs.org/wgbh/buildingbig/wonder/structure/golden_gate.html. Accessed October 2005.
Keipper K. Golden Gate Bridge Engineering Triumph
http://cems.alfred.edu/students/keippeka/default.html. Accessed October 2005.
Bridge Pros: Golden Gate Bridge.
http://www.bridgepros.com/projects/Goldengate/Golden_Gate.htm. Accessed October 2005.
Moran M. Suicide barrier sought for Golden Gate Bridge. Psychiatric News, 40 (7). April 1, 2005, p. 21. http://pn.psychiatryonline.org/cgi/content/full/40/7/21. Accessed October,2005.
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Accidental needlesticks are a common and potentially serious occupational hazard for health care providers. Needlesticks can transmit HIV, hepatitis B and C, and other blood-borne diseases. An accidental needlestick can have psychological as well as physical effects on the exposed worker.
Between 1985-1996, the Mayo Clinic in Rochester instituted numerous practice changes to reduce needlesticks for its 200 full-time equivalent phlebotomists. These changes included modification of the phlebotomy chairs, automatic disposal of plastic tube holders after each use, use of one-handed recapping blocks, elimination of a double-needle technique for collecting blood culture specimens, and intensive safety training. During this period, the needlestick injury rate fell from 1.5 to 0.2/10,000 venipunctures. In other words, since a phlebotomist can perform about 10,000 venipunctures per year, the average number of needlesticks per five years period for a full-time phlebotomist fell from 7.5 to 1. Similarly, a comprehensive approach at Arlington Hospital saw a 61% drop in needlestick injuries in a four year period.
Moral: Successful injury prevention requires a comprehensive approach, with many small beneficial improvements.
Sources:
Dale JC, Pruett SK, Maker MD. Accidental needlesticks in the phlebotomy service of the Department of Laboratory Medicine and Pathology at Mayo Clinic Rochester. Mayo Cllinic Proceedings. 1998; 73:611-615.
Zafar AB, Butler C, Podgorny JM, Mennonna PA, Gaydos LA, Sandiford JA. Effect of a comprehensive program to reduce needlestick injuries. Infection Control and Hospital Epidemiology. 1997; 18:712-715.
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Tractor Rollovers
Farm workers are at high risk for fatal injury. Historically, a major problem has been tractors rolling over and crushing the driver. The risks are heightened in the case of wheeled tractors with high centers of gravity; special hazards arise when the tractor is towing other equipment. Sloping or uneven ground, soft earth, ditches, trenches and excavations are contributing causes for rollover. Attempts to reduce the likelihood of rollover have not been very successful. For example, an engine cut-off switch to shut off power upon sensing lateral movement was introduced on tractors, but proved too slow with the dynamic forces generated in the rollover movement. However, tractors can be made so that, given a rollover, injury is less likely to occur.
The mounting of a protective frame or crush proof cab (known as rollover protective structures or ROPS) can prevent injuries due to a tractor rollover. The idea of rollover protection started in the 1920s, as tractor rollovers became prevalent in the agricultural community. However, before 1960, few tractors had such protection. In 1959 Sweden became the first country to mandate ROPS, on all new farm tractors, and despite opposition by farmers, the requirement was later expanded to all existing tractors.
From the period 1957-64 to 1986-90, the proportion of Swedish tractors with ROPS increased steadily from 6% to 93%. Over those same periods, the tractor rollover fatality rate fell from 12 per 100,000 tractors (23 fatalities per year) to 0.2 per 100,000 tractors (fewer than 1 fatality every two years).
Moral: Passive (automatic) safety measures are often highly effective for reducing injury.
Sources:
Springfeldt B, Thorson J, Lee BC. Sweden's thirty-year experience with tractor rollovers. Journal of Agricultural Safety and health. 1998; 4:173-180.
Springfeldt, B. Rollover. International Labour Office: Encyclopaedia of Occupational Health and Safety. http://turva.me.tut.fi/iloagri/natu/rollo.htm
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In the early 1890s, railroads were one of the major industries in the United States, and American railway workers were at high risk of injury-much higher than their European counterparts. The train crew, or trainmen, were at particular risk; if the fatality rates of the early 1890s had continued for thirty years, about 24 of 100 trainmen would have died of injuries on the job. During this period almost half of all trainmen died performing two tasks-coupling the cars together and braking them.
Link-and-pin coupling required that the trainman stand between cars that were coming together and guide the link into the slot. Trainmen were often crushed between the mammoth vehicles. Individual hand brakes required that a trainman ride on top of the car. Many workers died when striking overhead obstructions and/or falling from cars.
The automatic coupler, developed by Eli Janney, and the air brake, developed by George Westinghouse, were very slowly being introduced to freight trains. In 1893, the federal Safety Appliance Art mandated the use of both these new technologies. Over the next decades, "learning by doing" led to further improvements in the design, maintenance and method of use of these devices. Between 1890-91 and 1908-09, the death rate per trainman from coupling fell 66%, and for braking (falls from cars and striking overhead obstructions) fell 53%.
Moral: Work today is typically far safer than it was at the end of the 19th century.
Source:
Mark Aldrich. Safety First: Technology, Labor and Business in the Building of American Work Safety, 1870-1939. Baltimore, MD: Johns Hopkins University Press, 1997.