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Author Archives: Anonymous

Identify which of the following is a factor of the polynomia…

Identify which of the following is a factor of the polynomial, z 2 + 10 z + 25 {“version”:”1.1″,”math”:”z^2+10z+25″}

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Solve the equation,  12 − w = w {“version”:”1.1″,”math”:”\…

Solve the equation,  12 − w = w {“version”:”1.1″,”math”:”\sqrt{12-w}=w”}

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Factor the polynomial:  49 − 16 w 2 {“version”:”1.1″,”math…

Factor the polynomial:  49 − 16 w 2 {“version”:”1.1″,”math”:”49-16w^2″}

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The incident site was an underground transformer vault locat…

The incident site was an underground transformer vault located in the downtown area of a large city. The concrete vault measuring 80 feet long, 10 feet wide, and 12 feet deep, lies beneath an alley between two large buildings. Concrete and steel grating (the grating covers approximately 20% of the top) covers the top of the vault and forms part of the driving surface of the alley. Located on the top (at each end and in the middle) are three 27-inch-diameter utility hole openings, equipped with vertical, steel ladders attached at the top and embedded in the concrete at the bottom of the vault.The vault houses eight 480-volt transformers. Two 220-Volt sump pumps (one at each end) were initially installed to remove water that accumulates in the vault. Each pump is designed to operate using a float valve switch mechanism, with water intake pipes submerged in a sump well 18 inches square and IS inches deep below the vault bottom.An underground 220-volt cable supplies electric power. The power cable enters the vault and passes through two fuse boxes (located about half-way up the side of the vault), one serving the sump pumps and one serving to light along the vault coiling. Maintenance did not install a sufficient electrical ground when they installed the pumps. Later (about five years before this incident), an electrical short circuit developed inside one of the pump motors, blowing the fuses and de-energizing the pumps. The company decided not to repair the sump pumps, but to pump water from the vault with truck-mounted pumps periodically. After maintenance chose not to restore the pumps, they decided not to remove the fuse box, wiring, pumps, and piping.Over time the “moisture-proof” fuse boxes filled with condensate water and became heavily corroded. The corrosion bridged across the blown fuses, re-energizing the sump pumps and the pump frame and water discharge pipe of the short-circuited pump at a level of approximately 120-volts. On March 11, 1988, two power company employees, a lead cable splicer (the victim) and a winch truck operator (co-worker) were inspecting the circuit protectors on the transformers in the vault. The victim and co-worker arrived at the vault at about 8:30 a.m. Since the vault had approximately 33 inches of water in the bottom, the victim put on rubber hip waders, removed the utility hole cover at the east and of the vault, and entered the vault with a flashlight. While the victim was checking the circuit protectors on four transformers, the co-worker studied an electrical circuit map of the vault. The co-worker also directed vehicular traffic through the alley since there were no traffic cones or guard rails around the open utility hole.At about 8:40 a.m. the co-worker heard “a noise” inside the vault. When he looked into the utility hole, he saw the victim facedown in the water, halfway between the ladder and the sump pump (a horizontal distance of about 4 feet). The co-worker did not observe the position of the victim immediately before seeing him facedown in the water. Circumstantial evidence suggests that the victim contacted an energized component of the sump pump (either a metal pipe, part of the housing, or another connected apparatus) with his right hand and the steel ladder (which was at ground potential) with his left hand. This would have provided the current a path to ground through the victim. Current may have entered his right hand, passed through his chest, and exited his left hand, resulting in his electrocution. Presumably, the victim then fell forward, breaking contact.In a rescue attempt, the co-worker entered the utility hole, descended the ladder, and stretched out one hand and pulled the victim’s face out of the water. However, when the co-worker stopped off the ladder onto the floor of the vault he felt a shock, so he stopped back on the ladder. It is believed that since the co-worker was not wearing rubber hip waders, his foot was at some level of ground potential when it touched the vault floor. While managing to hold the victim’s face out of the water with one hand and the ladder with the other hand, the co-worker called out for help.Several passersby responded and made several unsuccessful attempts to help the co-worker remove the victim from the vault. However, they were hampered by electric shocks they received from either structural steel beams that crossed the inside of the vault or the vault bottom. Another factor that made rescue difficult was the victim’s relatively large size and weight. At least three attempts were made to hoist the victim out of the vault with handling tied around the victim’s chest. Each time, the victim slipped through the rope and fell to the bottom of the vault. One of the passersby made an emergency call on the company truck radio. A policeman arrived and then minutes later paramedics, each attempting to assist in the rescue effort, and each experiencing electric shocks in the process.According to rescuers, the power company cut off the power to the vault approximately 35 minutes from the time the victim was first observed facedown in the water. Paramedics found that the victim was “still breathing a little” ‘and had a slight pulse. Shortly after the power was turned off, a manual respirator was lowered into the vault and used in an attempt to resuscitate the victim. Attempts to remove the victim from the vault were unsuccessful until the fire department rescue squad arrived.Rescuers ultimately succeeded in putting a body harness around the victim and hoisting him out of the vault with the use of a truck-mounted winch. The total time from when the victim was observed unconscious in the vault to when he was removed was estimated at approximately 1 hour and 20 minutes.Paramedics initiated cardiopulmonary resuscitation (CPR) after the victim was removed from- the vault, and continued to administer CPR while en route to a local hospital. The victim was pronounced dead on arrival by the attending physician.Identify the OSHA Regulations that should be observed with working with energized equipment.Is this a permit-required confined space? Why or Why not?Identify the violations of the OSHA regulations that could have prevented this incident.Identify the Lockout / Tagout procedures that should have been taken to prevent this incident from occuring.

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The sawmill where the accident occurred has a city water lin…

The sawmill where the accident occurred has a city water line running underground (through a vault) along the front of their property. The below-ground vault which measures twelve feet long, six feet wide, and eight feet deep with a 30-inch utility hatch at the ground level was installed in 1978 to house a backflow device on the city water line. A backflow device is required to protect the city water supply from possible contamination in the event of negative pressure on the water line. The sawmill’s fire protection system connects to this water supply; and requires a backflow device. The city mandates the annual inspection of backflow devices by a person trained and certified in cross connection control.The independent contractor (the victim) called the superintendent of maintenance on October 6, 1986, to set up a date and time to inspect the backflow device on the water line. The date and time mutually agreed upon was October 10th at 3: 30 p.m. The contractor arrived at the sawmill at 3:30 p.m. on October 10th and proceeded with the inspection, which he had completed annually for the past three years. The contractor removed the steel hatch and lowered a ladder into the eight-foot-deep vault. There were 14 inches of water in the bottom of the vault.At 4:00 p.m. a truck driver stopped at the sawmill office to inquire about a load of lumber he was to pick up. When he walked out of the office, he noticed the victim’s truck and an open utility hatch close to where he would have to drive through. He walked over to the open hatch and saw a body in the water at the bottom of the vault. The driver went back to the office and reported a man was down in the vault. The secretary called the emergency squad. After calling the emergency squad, the secretary and truck driver went outside to the utility hatch. The secretary called for help, and the first to arrive at the scene was the shipping supervisor, who entered the vault in a rescue attempt. A few seconds later, one of the maintenance men arrived on the scene and descended into the vault to assist in the rescue. The men did not have respiratory protection on and within two or three minutes both men had passed out.Two policemen arrived at the scene, entered the vault (without respiratory protection), and had to be helped out. The paramedics arrived and attempted rescue (without respiratory protection) and also had to be helped out. The firemen arrived on the scene, donned their breathing apparatus, and went in to remove the three men at the bottom. Two were face down in the water (the contractor and the shipping supervisor), and the third man (the maintenance man) was in a sitting position against the wall, his head was not in the water.Firefighters transported the three victims (the contractor, the shipping supervisor, and the maintenance man), the two police officers, and the two paramedics to a local hospital. The contractor and shipping supervisor were pronounced dead on arrival by the attending physician. Doctors declared the maintenance man as in serious condition. The hospital staff treated and released the two policemen and two paramedics.Test of the atmosphere in the vault by the state investigators revealed the following:02 7%C02 > 3%% LEL NegativeH2S NegativeIdentify the specific OSHA regulations that should be followed when entering a confined space.Is this a permit-required confined space? Why or Why not?Identify the violations of the OSHA regulations that could have prevented this incident.Identify the Personal Protective Equipment that should have been worn in this scenario.

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This matching section covers American warriors from this uni…

This matching section covers American warriors from this unit. 

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The French had a war plan to defeat Germany in 1914 known as…

The French had a war plan to defeat Germany in 1914 known as Plan 17 that had been in the preparation stage since the 1890s. 

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Theodore Roosevelt considered the greatest accomplishment of…

Theodore Roosevelt considered the greatest accomplishment of his presidency was negotiating an end to the Russo-Japanese War of 1906 which won him his Nobel Peace Prize. 

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The U.S. Congress adopted an income tax because it offered t…

The U.S. Congress adopted an income tax because it offered the ability to raise more revenue and could be directed at high earning citizens. 

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Theodore Roosevelt led the Rough Riders up San Juan Hill dur…

Theodore Roosevelt led the Rough Riders up San Juan Hill during the Spanish American War. 

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