Solutions Manual: Ch10-Motion Study-s Review Questions 10.1 What is motion study? Answer: Motion study is the analysis of the basic hand, arm, and body movements of workers as they perform manual work or other physical activity. 10.2 What is work design? Answer: Work design is the design of the methods and motions used to perform a task, the workplace layout and environment, and the tooling and equipment (e.g., workholders, fixtures, hand tools, portable power tools, and machine tools). Work design is the design of the work system. 10.3 What is a therblig? Answer: A therblig is a basic motion element, the basic building block of virtually all manual work. The 17 therbligs were defined by Frank Gilbreth, who devised the word therblig by spelling his own name backwards (except for the “th”). 10.4 Identify some of the ineffective therbligs. Answer: The eight therbligs classified as ineffective in the text are hold, pre-position, position, search, select, plan, unavoidable delay, and avoidable delay. 10.5 What is the term sometimes used for the kind of analysis involving therbligs in a task? Answer: Micromotion analysis. 10.6 What are the general objectives of micromotion analysis? Answer: The general objectives listed in the text are the following: (1) Eliminate therbligs that are ineffective if possible; for example, eliminate the need to search for parts or tools by positioning them in a known and fixed location in the workplace. (2) Avoid the use of the hand for holding parts; use a workholder instead. (3) Combine therbligs where possible; for example, perform right hand and left hand motions simultaneously. (4) Simplify the overall method; for example, by re-sequencing therbligs in the cycle. (5) Reduce the time required for the motion; for example, shorten distances of therbligs such as transport empty and transport loaded. 10.7 Name some of the principles of motion economy that deal with the use of the two hands. Answer: There are five principles given in the text that are identified as principles of motion economy that deal with the use of the two hands: (1) Design the work so that both hands are fully utilized. (2) The two hands should begin their motions at the same time and end their motions at the same time. (3) The motions of the hands and arms should be symmetrical and simultaneous. (4) The work should be designed to emphasize the worker’s preferred hand. (5) The worker’s two hands should never be idle at the same time. 10.8 Why are smooth continuous curved motions better than straight-line motions when performing manual work? 1 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s Answer: Smooth continuous curved motions are better because straight-line motions involve abrupt changes in direction, which require deceleration and acceleration. These stop and start motions tend to cause greater fatigue for the worker than smooth continuous curved motions. 10.9 What is the lowest classification of hand and arm motions? Answer: The lowest classification of hand and arm motions is finger motions only. 10.10 What is the difference between eye focus and eye travel? Answer: Eye focus is when the eye adjusts to a change in viewing distance, for example, from 25 inches to 10 inches with little or no change in line of sight. Eye travel occurs when the eye must adjust to a line-of-sight change, for example, from one location in the workplace to another, but the eye focus distances are the same. 10.11 What advantage does the use of the legs have over the use of the arms? Answer: The legs are stronger. This might be helpful in lifting tasks. 10.12 What is a gravity feed bin and what is its advantage over a simple tray? Answer: A gravity feed bin is a container that uses gravity to move the items in it to a convenient access point for the worker. It generally allows for quicker acquisition of an item than a conventional tray. 10.13 What are the desirable adjustments on a chair designed for the workplace? Answer: The desirable adjustments usually include seat height and back height, as well as a means of increasing and decreasing the amount of back support. Also, both the seat and back should be padded. 10.14 Why are multiple-function tools better than separate tools for each function? Answer: Less time is usually required to reposition a multiple-function tool than to put one single-function tool down and pick another one up.
Problems Therbligs 10.1 The plumber, kneeling on the floor next to the sink, reached for the monkey wrench in his tool kit, pushing around a few other tools before grasping the wrench and picking it up. He then moved it to the pipe beneath the sink, positioned it onto the pipe fitting, and turned the fitting one-third of a rotation to loosen it. Once loose, he put down the wrench and continued turning by hand. Four rotations were required before the fitting was free of the mating pipe threads, during which he had to grasp and regrasp the fitting ten times due to the limited rotation ability of his own wrist. Write a list of the therbligs that comprise this motion sequence and label each basic motion with a brief description. Solution: List of therbligs with descriptions. We assume the plumber is right-handed and the dominant motion elements are performed with the right hand. The sequence begins with the plumber kneeling in front of the sink. 2 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s Seq.
Therblig symbol TE Sh St G TL PP U TL RL TE G DA
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
Therblig name
Description
Transport empty Search Select Grasp Transport loaded Pre-position Use Transport loaded Release load Transport empty Grasp Disassemble
Reach for monkey wrench Search for monkey wrench in tool kit Select the monkey wrench Grasp the monkey wrench Move wrench to pipe beneath sink Position wrench onto pipe fitting Rotate wrench to loosen pipe fitting Move wrench away from pipe fitting Put down wrench Move hand back to pipe fitting Grasp pipe fitting Turn pipe fitting by hand to separate
10.2 The secretary reached for the envelope with her right hand, picked it up and exchanged it to her left hand. She then reached for the letter opener with her right hand, picked it up, positioned the blade under the sealed lid of the envelope, and proceeded to slit the top of the envelope open. Still holding the envelope in her left hand, she laid the letter opener aside, and reached into the envelope with her right hand, pulled out the document, and began to read. Write a list of the therbligs that comprise this motion sequence and label each basic motion with a brief description. Solution: List of therbligs. Seq.
Left hand
1. 2. 3. Reach to exchange envelope 4. Grasp envelope 5. Hold envelope 6. Hold envelope 7. Hold envelope 8. Position envelope 9. Hold envelope 10. Hold envelope 11. Hold envelope 12. Hold envelope 13. Hold envelope 14. Hold envelope
Therbligs TE
Right hand Reach for envelope
G
Grasp envelope
TE
TL
Move envelope to left hand
G
RL
Release envelope
H
TE
Reach for letter opener
H
G
Grasp letter opener
H
TL
Move letter opener
P
P
Position blade under seal
H
U
Use letter opener
H
TL
Lay the letter opener aside
H
RL
Release letter opener
H
TE
Reach into envelope
H
G
Grasp the document
H
TL
Pull out the document
10.3 The grocery store checkout clerk picked up the item from the checkout table and moved it across the bar code scanner. Immediately, the scanner audibly responded that it had successfully identified and recorded the item. Since this was the only item the customer had brought into checkout lane, the clerk punched one of the buttons on the cash register to 3 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s print out the sales slip. While the register printed, the checkout clerk placed the item into an open plastic bag in front of him, picked up and closed the bag, and handed it to the customer. Write a list of the therbligs that comprise this motion sequence and label each basic motion with a brief description. Solution: List of therbligs. Seq.
Left hand
1. 2. 3. 4. Move toward cash register 5. Position finger over key 6. Punch button on register 7. Move to bag 8. Grasp bag 9. Move bag toward item 10. Hold bag 11. Hold bag 12. Release bag 13. 14.
The TE
Right hand Reach for item on checkout table
G
Grasp item on checkout table
TL
Move item across scanner
TE
H
Hold item
P
H
Hold item
U
H
Hold item
TE
H
Hold item
G
H
Hold item
TL
TL
Move item toward bag
H
PP
Position item into bag
H
TE
Move to hold the bag
RL
G
Grasp bag
TL
Hand bag to customer
RL
Release bag to customer
10.4 Sitting at her desk, the writer reached for the mechanical pencil, picked it up, positioned it, and then began to write on the pad of paper. After finishing one sentence, she lifted the pencil, and read the sentence. She then put the pencil aside and reached for the rectangular eraser nearby. Grasping and positioning it, she erased one of the words in the sentence. Write a list of the therbligs that comprise this motion sequence and label each basic motion with a brief description. Solution: List of therbligs. Seq. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Therblig symbol TE G TL U TL H I TL RL TE G
Therblig name
Description
Transport empty Grasp Transport loaded Use Transport loaded Hold Inspect Transport loaded Release Transport empty Grasp
Reach for mechanical pencil Pick up pencil Position pencil relative to paper Write on the pad of paper Lift the pencil Hold the pencil Read the sentence Move the pencil to put it aside Put pencil aside Reach for the rectangular eraser nearby Grasp the eraser 4
Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s 12. 13.
P U
Position Use
Position the eraser over the word Erase one of the words in the sentence
10.5 For the previous problem, identify some areas for possible study that might improve the method, indicating the nature of the improvement that might result. Solution: Areas for possible study to improve the method include the following: 1.
Minimize the distance of the reach to the pencil and eraser by locating items in the workplace in close proximity to each other.
2.
Instead of using a rectangular eraser, use a stick eraser. This allows much more precise control over the area to be erased.
3.
Better yet, use a pencil equipped with an eraser to avoid having to put the pencil aside and pick up the separate eraser, then put the eraser aside and pick up the pencil.
4.
Instead of a pencil and paper pad, use a personal computer equipped with word processor. This allows for much easier editing than pencil and eraser.
10.6 The worker reached for the small part a short distance away in the workplace, picked up the part, and placed it in a vise. The worker then rotated the screw handle of the vise three turns to hold the part between the vise jaws. In rotating the screw handle, he had to grasp and regrasp the handle six times due to the limited rotation ability of his own wrist. On the final turn, he applied additional torque to tighten the vise. Write a list of the therbligs that comprise this motion sequence and label each basic motion with a brief description. Solution: List of therbligs. Seq. 1. 2. 3. 4. 5. 6. 7. 8.
Therblig symbol TE G TL P H TE G U
Therblig name
Description
Transport empty Grasp Transport loaded Position Hold Transport empty Grasp Use
Reach for the small part a short distance away Grasp the part Move part toward vice Position part in vice Hold part in vice with one hand Reach for vice handle with other hand Grasp vice handle Rotate screw handle to tighten vice (six times)
10.7 For the previous problem, identify some areas for possible study that might improve the method, indicating the nature of the improvement that might result. Solution: Areas for possible study to improve the method include the following: 1.
Minimize the distance of the reach to and transport of the small part by locating items in the workplace in close proximity to each other.
2.
Instead of a conventional vice with screw handle to close jaws, equip the workstation with a fast-acting pneumatic clamp. Then the worker would position the part with one hand and actuate the clamp with the other in two quick motions. 5 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s 3.
Assuming the operation performed by the worker is a repetitive cycle, the part could be presented to the worker using a dispenser that would locate the part in an exact position at the start of each cycle. This would eliminate reaching “for the part a short distance away in the workplace,” before placing it in the vice.
4.
Better yet, the dispenser could be designed so that it also served as the workholder for the cycle. Then the worker would not have to get the part and place it in a separate workholder. The part would already be in the workholder.
10.8 The assembly worker reached for an Allen wrench in the workplace, hesitating momentarily while searching for the correct size from the group of Allen wrenches lying there. Finding the correct size, she picked it up and positioned it into the hexagonal socket of a screw that had previously been hand-turned into a threaded hole in the work unit. She then twirled the Allen wrench handle with one continuous finger and wrist motion until the screw had been rotated seven turns. At this point she gripped the Allen wrench handle with her hand and tightened the screw the last quarter turn. Write a list of the therbligs that comprise this motion sequence and label each basic motion with a brief description. Solution: List of therbligs. Seq. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Therblig symbol TE St G TL P RL TE U TE G U
Therblig name
Description
Transport empty Select Grasp Transport loaded Position Release Transport empty Use Transport empty Grasp Use
Reach for the Allen wrench in the workplace Select the correct size Grasp the Allen wrench Pick up and move Allen wrench toward screw Position Allen wrench into hexagonal socket Release grip on Allen wrench Move wrist and finger in preparation for turning Twirl Allen wrench with one continuous motion (6 turns) Reposition wrist and hand Grip Allen wrench in preparation for tightening Tighten screw with Allen wrench (quarter turn)
10.9 For the previous problem, identify some areas for possible study that might improve the method, indicating the nature of the improvement that might result. Solution: Areas for possible study to improve the method include the following: 1.
Minimize the distance of the reach to the Allen wrench by locating items in the workplace in close proximity to each other.
2.
Instead of having an entire set of Allen wrenches in the workplace, have only the correct size of wrench in the workplace. This would eliminate the need for the worker to search for the correct size from a group of Allen wrenches. It minimizes the requirement for hand-eye coordination during the reach.
3.
Instead of using the conventional L-shaped Allen wrench, use a screwdriver equipped with a hexagonal tip of the particular size needed. A screwdriver is generally easier to 6 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s use than an Allen wrench. The worker could perform the turning and tightening in one element rather than separating the “twirling” and “tightening” elements. 4.
A powered screwdriver equipped with the correct hexagonal tip could be used rather than a manual tool. The powered screwdriver could be set to deliver just the correct amount of torque, rather than rely on the judgment of the worker.
5.
If the powered screwdriver also had a screw feeder, the previous work element of hand turning the screw into the threaded hole could be eliminated. Thus, the entire sequence of starting the screw into the hole, turning it six times, and then tightening it could be accomplished in one short element.
Principles of Motion Economy 10.10 Charles Dickens continued working well into the night, writing with his quill on one piece of paper after the next, the only light provided by the lone candle in front of him on the desk. (a) Identify some of the principles of motion economy that seem to be violated by Dickens’ method of working and workplace. (b) Make recommendations for improving the work method and workplace. Solution: (a) Principles of motion economy that seem to be violated include the following: 1.
Adequate illumination must be provided for the workplace. Adequate illumination is not provided by “the lone candle in front of him on the desk.”
2.
In addition, the position of the candle (”in front of him on the desk”), although it provides less than adequate illumination, probably causes glare. The light source would better be placed to the side so that it does not shine directly in Dickens’ face.
3.
Hand tools should be designed for operator comfort and convenience. The quill used by Dickens, although it might have been the contemporary writing tool of the times, is not as efficient as modern writing instruments like mechanical pencils and ballpoint pens. The quill must be periodically dipped into an ink reservoir, probably several times per sentence, thus slowing down the writing process. Although he was not aware of it, Dickens’ hand tool was not designed for maximum comfort, convenience, and utility.
4.
Manual operations should be mechanized or automated wherever economically and technologically feasible. Although it was not technologically feasible in Dickens’ time, today the task of writing is largely performed using personal computers equipped with word processing software.
(b) Recommendations for improvement include the following (these improvements would not have been technologically possible during Dickens’ life; we mention them anyway): 1.
Use overhead lighting that provides sufficient illumination for the task. (Recommended illumination levels are discussed in Section 25.1.)
2.
Use a writing instrument other than a quill. Use a mechanical pencil or ballpoint pen instead.
3.
Use a word processor on a PC. 7 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s 10.11 The assembly worker is performing a repetitive manual task consisting of inserting 8 plastic pegs into 8 holes in a flat wooden board. A slight interference fit is involved in each insertion. Each work cycle consists of her picking up a board from the stack of boards located on the left side of the worktable (about 15 inches away from center, where they are placed by a material handling worker), performing the 8 insertions, and then placing the assembled board into a rack that is next to the starting stack. Her first step in the work cycle is to reach for the top board in the stack with her right hand, pick it up, and exchange it to the left hand. While holding the board in her left hand, she picks up the pegs from a tray about 10 inches away in front of her with her right hand and inserts them into the holes in the board, one peg at a time. The rack holding the completed boards has a capacity of six assemblies. When the rack is full, the worker gets up from her worktable, picks up the loaded rack, carries it to a pallet located on the floor three feet away from the workplace, and places it onto the pallet. The pallet only holds four racks on one layer. A material handling worker riding in a forklift truck must periodically take the pallet away and replace it with an empty pallet. Because of delays by the material handling worker, the assembly worker is occasionally forced to stop working and wait for the pallet exchange to occur. (a) Identify some of the principles of motion economy that are violated in this work cycle. (b) What recommendations for improvement would you make? Solution: (a) and (b) Principles of motion economy that seem to be violated and corresponding recommendations for improvement include the following: 1.
Workholding devices should be designed for the task; a worker’s hand should not be used as a workholder. The worker uses her left hand simply to hold the board. A workholder should be designed for the task.
2.
Design the work so that both hands are fully utilized. Because the left hand is used only as a workholder, it is not fully utilized. The method should be redesigned so that both hands are inserting pegs into the board while the board is being held in a workholder.
3.
The work should be designed to emphasize the worker’s preferred hand. Because she reaches for “the top board in the stack with her right hand” even though the board is located “on the left side of the worktable (about 15 inches away from center), we can infer that the worker is right-handed. Yet the starting boards are located on the left side of the workplace. They should be located on the right side if the right hand is used. If there is some reason why the stack must be located on the left side of the workplace, then she should acquire the top board with her left hand.
4.
The worker’s two hands should never be idle at the same time. “Because of delays by the material handling worker, the assembly worker is occasionally forced to stop working and wait for the pallet exchange to occur.” The worker is idle and so are both of her hands.
5.
The lowest classification of hand and arm motions should be used. The task description states that the worker “picks up the pegs from a tray about 10 inches away in front of her with her right hand and inserts them into the holes in the board, one peg at a time.” The implication is that the forearm and upper arm are used for each 8 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s peg – reaching for the pegs “one at a time” in a tray that is 10 inches away. The worker should pick up several pegs at a time and insert them all before going back to the tray for more. This would require finger and wrist motions for the insertions. If she could handle 4 pegs at a time in each hand, then all 8 pegs could be retrieved using two simultaneous upper arm trips to the tray rather than 8 trips using one hand to retrieve one peg each trip. 6.
Tools and materials should be located close to where they are used. There are several violations of this principle: (a) The placement of the starting stacks and racks to receive the finished boards, located 15 inches to the left of workplace center, are not optimally positioned in the workplace. A location closer to center would be an improvement. (b) The same comment applies to the location of the tray holding the pegs. It is currently 10 inches away. The time to acquire the pegs could be reduced if the tray were closer. (c) “The rack holding the completed boards has a capacity of six assemblies. When the rack is full, the worker gets up from her worktable, picks up the loaded rack, carries it to a pallet located on the floor three feet away from the workplace, and places it onto the pallet.” This is very inefficient. The pallet should be in an elevated location much closer than three feet away so that the worker can move the rack more conveniently.
7.
Gravity feed bins should be used to deliver small parts. Instead of using a tray to hold the pegs, use a gravity feed bin. The capacity of the gravity feed bin would probably be greater than the capacity of a tray.
8.
Manual operations should be mechanized or automated wherever economically and technologically feasible. A conveyorized workstation could be implemented to feed the boards to the worker one at a time, instead of requiring her to reach for the empty boards at the beginning of each cycle and then place the assembled boards in a rack at the end of the cycle. This mechanized method would also avoid requiring the worker to place the filled rack onto a pallet every six boards. An automated storage device could be designed to hold a large supply of starting boards and to feed them to the conveyor system. A similar storage device could be designed to accept the assembled boards as they are completed. Such a system would achieve a much higher production rate because it would avoid (a) the irregular work elements to change racks and load pallets and (b) the forced delays when the material handler does not arrive on time.
10.12 Sitting in front of her all-wooden desk in her all-wooden chair, the author reached for her wooden pencil, picked it up, positioned it, and then began to write on the pad of paper. After finishing one sentence, she lifted the pencil, and read the sentence. She then put the pencil aside and reached for the eraser nearby. Grasping and positioning it, she erased one of the words in the sentence. She then laid the eraser aside, picked the pencil up, made a correction, and continued writing. Periodically, she would repeat this sequence of writing, erasing, correcting, and then continuing to write. After working in this way for about two hours, she went and took a nap. (a) Identify some of the principles of motion economy that are violated in this work sequence. (b) What recommendations for improvement would you make? 9 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s Solution: (a) and (b) Principles of motion economy that seem to be violated and corresponding recommendations for improvement include the following: 1.
A proper chair should be provided for the worker. The all-wooden chair does not have the adjustments necessary to fit the chair to the worker’s anatomy for the writing task. An adjustable chair should be provided.
2.
Multiple tooling functions should be combined into one tool wherever possible. Use a pencil equipped with an eraser to avoid having to put the pencil aside and pick up the separate eraser, then put the eraser aside and pick up the pencil.
3.
Hand tools should be designed for operator comfort and convenience. Instead of using a rectangular block eraser, use a stick eraser. It allows much more precise control over the area to be erased.
4.
Design the work so that both hands are fully utilized. Instead of a pencil and paper pad, use a personal computer equipped with word processor. Both hands are used to depress the keys in the keyboard.
5.
Manual operations should be mechanized or automated wherever economically and technologically feasible. Instead of a pencil and paper pad, use a personal computer equipped with word processor. This allows for much faster creation of the document and easier editing than pencil and eraser.
10.13 The Calm Seas Cruise Ship Line wants to analyze the method used by its stewards to clean each of the passenger cabins on its ships. The current method used by a steward to clean one cabin is the following. First the steward knocks on the cabin door with his right hand to determine if the room is empty. Given no response, the steward reaches for his master key in his pocket, unlocks the door, opens it slightly and yells “housekeeping.” If there is still no answer, he walks into the room to look around. After looking around, he goes back out into the hallway, and pushes his cart into the room. He then goes back into the hallway for his vacuum cleaner and carries it into the room. His first cleaning step is to vacuum the room and adjoining bathroom. He then strips the bed linen, puts it into the hamper on his cart, goes back into the hallway and walks down to the closet where the fresh bed linens are kept. He picks out a set of linen, carries them back to the room, and proceeds to make the bed. Next, he walks into the bathroom, picks up the used towels and carries them out to the cart hamper. He then goes back into the hallway and walks down to the same closet as before to obtain fresh towels for the room. He brings the towels back and places them onto racks in the bathroom. From his cart, he obtains fresh soap items for the bathroom. His final cleaning step is to pick up any trash items that may have been left in the room by the passengers. (a) Identify some of the principles of motion economy that are violated in this method. (b) Besides the principles of motion economy, what other deficiencies in the method can you identify? (c) What recommendations for improvement in the method would you make? Solution: (a) Principles of motion economy that seem to be violated include the following:
10 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
Solutions Manual: Ch10-Motion Study-s 1.
Materials should be located close to where they are used. In the current method, the towels and bed linens are located in a closet that is somewhere in the hallway away from the cabin.
2.
Tools should be located in fixed positions within the work area. The vacuum cleaner location seems to violate this principle because it is not attached to the cart.
3.
Tools and materials should be placed in locations that are consistent with the sequence of work elements in the work cycle. The fact that the towels and bed linens are located in the hallway closet violates this principle.
4.
Portable powered tools should be designed for operator comfort and convenience. Why does the steward have to carry the vacuum cleaner into the room? It should be equipped with wheels that make it easy to maneuver into the room.
5.
Multiple operations should be performed simultaneously rather than sequentially wherever possible. The steward should collect the soiled bed linen and towels in one sweep of the cabin and put both into the cart hamper in the same step, rather than make two separate work elements, one for the linen and the other for the towels.
(b) Other deficiencies in the method include the following: 1.
What is the purpose of walking into the room and looking around before going back into the hallway to obtain the cart? Why not just push the cart into the room after yelling “housekeeping.”
2.
In the work sequence, the steward vacuums before stripping the bed. The bed linen should be stripped before using the vacuum cleaner to avoid items contained in the bed linens from dropping onto the freshly vacuumed carpet.
(c) Recommendations for improvement include the following: 1.
Include a holder on the cart to locate the vacuum cleaner, so the cart and vacuum can be moved simultaneously.
2.
The cart should include a space to hold the bed linens and towels so the steward does not have to make two trips to the closet to fetch them.
3.
The steward should not make two trips to the hall closet, one to fetch the bed linens and the other to fetch the towels. If the bed linens and towels must be obtained individually for each cabin, they should both be obtained in one trip for each cabin. Better yet, a supply of both items should be carried on the cart to minimize the trips back and forth to the closet.
11 Work Systems and the Methods, Measurement, and Management of Work by Mikell P. Groover. ISBN 0-13-140650-7. © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved.
