Unit 3 Assessment Safety Engineering

Unit 3 Assessment: Safety Engineering

Mroszcayk, 2012, Safety Engineering, Fourth Edition, ASSE

  1. Compare and contrast the different types of tribometers. In your opinion which of the tribometers best represents the slip resistance of a surface?
  2. Pendulum testers are one of the three classes of devices used to measure the slip resistance of walking surfaces. This testers component consists of a “shoe”, a sliding pad and a pendulum. The shoe slides across the surface of the sliding pad. As the swing continues there is friction lost. It is almost being simulating when a human heel strikes a surface while walking but not quite. This type only tests dynamic friction. Dynamic friction is a force measurement. Dynamic friction measures the amount of force that it takes maintain steady motion across a body relative to another because they remain in contact (Mroszcayk, 2012).
  3. Drag sheds can only be used on dry surfaces. These are weighted objects that are dragged across a surface. One such sled is the horizontal Pull Slip meter. It consists of a weighted sled and three pads. As the right amount of force is applied to the sled it begins to slip at this point a measurement can be made as to the slip resistance of the surface being tested. This device is subject to sticktion (Mroszcayk, 2012).
  4. The articulated inclinable Testers is used in laboratories. One such device is the James Machine. This machine is subject to sticktion. There is a pass/fail value given for surfaces. The value of .5 tends to be the value placed on passing test. There are other types of AIT’s but they all uses trigonometric relationships in defining slip resistance (Mroszcayk, 2012).
  5. Mroszcayk, 2012, Safety Engineering, Fouth Edtion, ASSE
  6. Compare and contrast the different types of barriers that might be used to protect openings in a floor at a production facility. What factors should an engineer take into account when designing one of these barriers? In your opinion, which type barrier would be most appropriate for an opening between all four floors of a facility that is designed to move material between floors using a crane located on the top floor?
  7. In a production facility there are human traffic and often raised platforms and floors on several levels of a building. There must be barriers in place to protect people from falling into these openings. A floor opening is such that the opening is greater than 12 inches in dimension.
  8. The standard railing is defined as being made of wood or metal and able to withstand loads of 200 pounds of force. The standard rail must have a smooth top rail at least 42 inches from the floor. A standard railing must be used if a raised platform is being used. Toeboards must be placed on rails if pedestrian traffic and work is being done below the raised surface. The toeboard must be 4 inches wide and there must be no more than a quarter inch clearance space in-between the bottom of the toe board and the floor. This is to prevent tools from falling off the platform or elevated surface onto the floor below. and the accidental slipping of a person’s foot pass the platform or elevated surface (Mroszcayk, 2012).
  9. Other types of barriers for floor openings are metal plates, catwalks and overhead balconies. Each barrier is used to specifically accommodate the need to protect walking surfaces. In a production facility there are several activities that are taking place but the main concern is the protection against slips and falls either of people or equipment.
  10. When designing a barrier an engineer must take into account the amount of human traffic, that the area is going to have, the type of loads that the walkways and platforms are going to handle, and the kind of industrial operation is going to be done within the facility. Engineer’s know how to use design formulas and equations. They use these calculations to make the best design that will handle load, bending movement, length of time design will be used, inertia and elasticity.
  11. I think the standard rail and traditional barriers such as manhole plates and railings are barriers that people notice and are familiar with.
  12. The type of barrier that would be most appropriate for an opening between all four floors of a facility and that is designed to move material between floors using a crane located on the top floor and lift platform elevators that is caged in by stationary railing or fence. This allows the person to be transported form level to level while also being protect from the crane activity, the possibility of loads falling, and they are good fall protection as they provide a barrier and protect against exposure of the elevation of the lift.
  13. Mroszcayk, 2012, Safety Engineering, Fouth Edtion, ASSE
  14. The Heat Stress Index (HSI) uses the terms O (Oxygen required), M (Metabolism), R (Radiation) C (Convection), and E (Evaporation). Compare and contrast the terms. Provide an example of a control method that you believe would be effective in controlling heat stress related to each of the terms M, R, C, and E.
  15. The human body is designed to handle extreme low and high temperatures. Within the body there is an interconnectedness of temperature regulations with oxygen, metabolism, radiation, convection and evaporation. The inner body’s temperature is maintained in close association with the ambient temperature around the body. The earth’s atmosphere is a little over 20% oxygen. The human body uses the oxygen in the air as it inhales through normal respiration to send throughout the body to connect with other atoms to form life sustaining compounds. Metabolism is the exchange of useful materials within the body as chemical compounds are moving around in the body, as it burns and use energy to keep the body’s organs and functions operational. It takes a healthy metabolism in regular work, rest and play to add to the comfort of human living. Radiation is the transfer of heat that the any heat source releases to the environment around it. The body’s temperature maintains a 98 degrees Fahrenheit regulation. As the body increase in temperature the more radiant heat will be felt from the body. The sun gives off its radiation and plants and animals benefits or is adversely affected by this radiation. The human body regulates the reception or rejection of outside heat. Convection is one such way the body and objects transfer heat. Unwanted heat is transferred from outside the body through sweat and ventilation through the body’s openings. The high heat capacity of water allows heat to be trapped inside the water molecules and placed on the skin. The humidity outside the body determines how much person will sweat because the sweat needs a place to evaporate or escape into the surrounding atmosphere as water vapor. Convection operates on the principal of fluids ability to contain heat, release and cool it. Heat travels at a level from low concentrations to high concentrations. The process of turning a liquid into a vapor is evaporation. The evaporation of sweat into water vapor is due impart to the radiation of heat on the skin from outside heat sources. In this interconnectedness of controlling heat the body manages heat stress and regulates low and high temperatures within the body (Mroszcayk, 2012).
  16. There are particle control methods for controlling heat stress and heat related illnesses that can be easily implemented during work, play or excursive. If in high temperature its best to wear light clothing and loose clothing. This allows the heat to escape from the body. Drinking water throughout the day also help hydrate and keeps the body supplied with water for sweating. A brief break in intervals away from the direct heat or radiation from the sun. Getting in shady areas help the body manage the heat. These methods of cooling the body relates in conjunction with oxygen, metabolism, radiation, convection and evaporation as explained above as the body use each process as a change-off for the extra heat that has invaded the body.
  17. You are evaluating heat stress in workers digging a ditch by hand to lay sewage pipes. You obtain the following average values over a two-hour period: Natural Wet Bulb (NWB) temperature = 27.0° C, Globe Temperature (GT) = 32.0° C, and Dry Bulb (DB) temperature = 30.0° C. Which WBGT index would you use to evaluate heat stress for this operation? Calculate a WBGT value for digging the trench. What control methods would you suggest reducing the risk of heat illness in these workers?
  18. WBGT = NWB + GT = DB
  19. WBGT = Wet-Bulb Globe Temperature
  20. NWB = Natural Wet Bulb
  21. DB = Dry Bulb
  22. 27.0 + 32.0 + 30.0 = 89.0
  23. WBGT = 89.0 DEGREES CELSIUS (Mroszcayk, 2012).
  24. The use of the Discomfort Index to evaluate heat stress for industrial occupations.
  25. The Discomfort Comfort Index can affect the productivity and the health of people and reduce tolerance to other environmental hazards. The DI is known as a universal heat stress index (Moran, 2006).
  26. The workers should be instructed to follow the OSHA guide for the amount of work and rest ratio times of rest and work periods. The workers should drink water throughout the day. If in the heat less than two hours and involved in moderate work activities drink one cup of water every 15-20 minutes. During prolonged sweating drink sports drinks containing a balance of electrolytes. They are to avoid alcohol, caffeine and sugar drinks. They should not drink six cups of water per hour, (OSHA, 2017).