the highest profit for a company. To many businesses, this is only a mirage. This is because the ‘low cost’ of the business usually results in a ‘high cost’ for the employees. This high cost is lower quality workplace items, lower salaries, less benefits, etc. These costs create an upset workplace environment. Companies understand that the more efficient their workers are, the more productive their business will become. Although this will take lots of money at first, the result will be extreme success.
There exist many different things in the workplace that add to stress and injuries. They range from lifting heavy boxes to typing too much on the keyboard. This paper will be focusing on the principals of ergonomics in the computer workstation. According to the Board of Certification for Professional Ergonomists (BCPE), the definition of ergonomics “is a body of knowledge about human abilities, human limitations and human characteristics that are relevant to design. Ergonomic design is the application of this body of knowledge to the design of tools, machines, systems, tasks, jobs, and environments for safe, comfortable and effective human use.”(BCPE, 1993) In the average computer workstation, employees are prone to over a dozen hazards. There exist two factors that can prevent this: forming good work habits and ergonomically designed computer workstations. We will discuss these
preventions throughout the paper.
First, a few terms may need defining. Repetitive Strain Injuries (RSI) takes place from the repeated physical movements of certain body parts which results in damage to tendons, nerves, muscles, and other soft body tissues. If these injuries are not taken care of immediately, permanent damage could be done. A few common results of RSI’s that were not taken care of right away are injuries like Carpal Tunnel Syndrome, Tendentious, Tenosynovitis, DeQuervain’s Syndrome, Thoracic Outlet Syndrome etc. All of these are able to be prevented by the use of good working habits and ergonomic engineering.
Usually, ergonomically designing a computer workstation would cost about $1000. This expense could be eliminated by the formation of good work habits. This is essential for the safety of computer terminal employees. There exist a number of precautions that can be taken into consideration when dealing with a computer workstation. We shall discuss six of them.
First, the whole body must be relaxed. The correct posture is shown in Figure 1. Notice that the arms and thighs are parallel to the floor and the feet are flat on the floor. Also notice that the wrists are not bent in any way. This is one of the most damaged parts of the body when speaking of (RSI).
The wrists, when typing, should not be rested on anything when typing. This would cause someone to stretch their fingers to hit keys. They should also be straight: not bent up, down, or to the side. The correct position is portrayed in figure 2, incorrect in figure 3. Studies show that these steps are easier to perform while the keyboard is not tilted toward the user. When it is tilted, it is natural to rest your wrists on the table. This puts the keyboard at a lower level, creating a more natural position.
Another practice that should be taken into consideration is how hard you press on the keys. The user is not supposed to hit the keys. This may cause damage to the tendons and nerves in the fingers. Instead, use a soft touch, not only will your fingers thank you for it, the keyboard will too!
Keeping in mind not to stretch your fingers when typing, use two hands to perform double-key operations. For example, you need to capitalize the first letter in every sentence, therefore, you would hold down the shift and press the first letter.
This is a double key operation. Instead of stretching two fingers on one hand to do this operation, use both hands.
No matter what kind of a pace you are on when doing work, take breaks every ten minutes or so in addition to your hourly breaks. These breaks need only be a few moments at a time. If breaks are not taken at this pace, you may be subjecting yourself to injuries in the back, neck, wrists and fingers. Also, when using the mouse, do not grip it tightly. Most mice that are used in offices today are not designed with human factors in mind. Some mice, like the Microsoft mouse, are designed to fit the contour of your hand. Although this may seem nice, it does not mean that one will be able to use it for hours on end and not feel any discomfort in the hand. Other mice, that will be mentioned later, are designed for comfortable use for extended periods of time.
Try to keep your arms and hands warm. Cold muscles are more apt
to strain and injury than warm ones. Wearing a sweater or a long-sleeved shirt can be of great importance especially when working in air-conditioned offices.
And finally, do not use the computer more than necessary. Your body can handle only so much strain on the neck, shoulders, wrists and fingers. Even with the greatest state-of-the-art ergonomically designed computer workstation, people put themselves at risk.
Some people tend to use their break times at work playing video games. This is a good way to ease the mind of everyday pressure (to some extent). This is also a good example of using the computer ‘more than necessary’. If a person needs to use a computer for video games, take a break every ten minutes or so, as mentioned above.ii
All of these strategies mentioned above are things that can be done to reduce injuries when using a computer for an extended period of time. They do not include any type of ergonomically designed hardware. If employees form these habits, there would be less need to purchase any ergonomic equipment for the office. But, making new habits is not the easiest thing to do for most people. Next, we will take a look at how a computer workstation should be set up. The following data was retrieved by an on-line quiz from the University of Virginia.
The first question about computer workstations poses a question about the seat being too high. This would cause strain on the legs of the operator causing them to “go to sleep”. Basically, the blood flow to the leg and feet will be cut off.
The next fact presented to us is that the top of the Video Terminal Display (VDT) should be no higher than eye level. This is one of the most controversial topics because it deals with the neck and shoulders. Some people state that it should be below, but not at eye level because our natural tendency is to look down.
Thirdly, the best viewing distance from the VDT is about 24 inches from the screen. This deals with eye strain. Some people worry about radiation that may be emitted from the VDT. Radiation is not a big problem with newer monitors. Even old ones have a protective coating around the screen. This allows very few particles to go through the screen. Even if they do manage to get that far from the screen, the radiation goes inches before withering away. The eye strain is the important factor here. Look away at an object far away from you if eye strain continues to be a problem.
The next question deals with the tilt of the screen. If the monitor should be at or below eye level, it would be easier to read with a 10 to 20 degree back tilt. Many VDT’s have a tilt on the bottom, if not, a book could propped under the monitor to tilt it back a bit.
Another question asked is about the height of the keyboard from the floor. It should be elbow height. As mentioned before, the fore-arms and thighs should be parallel to the floor. This is possible only if the keyboard is elbow height from the floor.
How should the lighting be in offices when using a computer? It should be a bit dimmer than normal office lighting. This is so because if the office lighting is brighter, there will be a lot of glare on the screen. It also has to do with eye strain.
Noise in the work area causes fatigue. This may be true, to add to this statement, it also causes the computer operator to lose concentration on their work. Not only does noise affect our concentration and causes fatigue, it obviously can damage one’s hearing.
Using this questionnaire, I conducted a survey among students at Canisius College in Buffalo, NY. The purpose of the survey was to test the knowledge of the student body as to their knowledge of VDT’s and their safety precautions. In order to accomplish this in a professional manner, a random sample of students was acquired. In order to obtain a random sample, certain criteria must be met, too numerous to mention in this essay. Needless to say, not all of the criteria were met for the sample to be random. The sample size of the survey was approximately 100 students. The results were not surprising. There was one problem with the questionnaire : many students did not know what VDT meant1.
According the survey, 100% of the people was familiar with what
ergonomics is, knew how to reduce tension, what movement in your peripheral vision does, and what you should do if you should wear bifocal lenses. This question posed a problem because of the way in which the answer was worded. The correct answer is very specific, and sticks out over the other possible answers. The rest of the questions were well worded and not too obvious.
Besides the first and last question, there were a few others that were all answered correctly. These were questions eleven and twelve. The probable cause for this is that the questions were easy. The answers were more obvious than the others. If you compare these questions to the ones that were more difficult (seven and thirteen) the percent correct differ. Questions seven and thirteen deal with very specific measurements that are all closely related. These questions are not ‘common knowledge’ questions. I am assuming that people were taking educated guesses when encountering these questions. This could be the reason for the large percent of error in these parts of the survey.
Now that we have discovered the good habits to form when working at computer workstations and took a look at what a selected college student population knew about VDT’s, we will now take a look at ergonomic engineering and the reason for its emergence.
There are a number of devices ranging from keyboards and mice to chairs and even foot stands. In this paper we will just review a few of these ergonomically designed items and why ergonomics is an issue to computer users.
First, we will discuss the purpose of ergonomically designed items. There are a number of reasons for the emergence of ergonomics. One reason for this is insurance purposes. Many companies have disability and other types of insurance to cover injuries that occur while working. This would not be needed as much if there were ergonomically designed computer workstations. It would save the company insurance hassle and money in the long run. Another purpose for the emergence of ergonomically designed workstations is that the injuries due to the overuse of the computers are long lasting. These ailments do not just go away in time. And one can not put a price on injuries like this. This is why ergonomics is so important.
Secondly, we will look at an item that effects the common computer
user the most: the keyboard. With computers getting faster and faster every day, it is about time that people looked at the hazards they pose instead of perfecting them. Keyboards pose the largest threat to the computer user, not only because it is the most used input device, but also because of its design. It is a flat, straight input device that can cause strain and injury to the user if not used properly. Ergonomic engineers realized this hazard and designed a number of different alternatives. All of the ergonomically designed keyboards attempt to reduce injuries by studying the natural position of the fingers, hands and wrists. By using this knowledge, keyboards and mice are designed. There is no ideal position for the hand as of yet. Hence, there exists different types of keyboards and mice. Figures 4 – 5 show different styles of keyboards and mice.
Figure 4 – http://www.earthlink.net/~dbialick/kinesis
Notice the unique structure of the keyboard. It does not even look like one. This may take time to get used to, but it will payoff in the end.
Not only is there hardware for the reduction of RSI, but there exists software to help you reduce the RSI. Micronite softwareiii
designed a program called ARMS (Against Repetitive Strain Injury) Which reminds you when it is time to take a break. Also, it walks you through a series of videos which portray ways to massage different parts of your hand, neck, and shoulders.
With all of this hardware and software available for business and personal use, who would not be interested? Well many people think that it will not happen to them until it does. People should not wait that long. If you use a computer for more than four hours a day, you are prone to RSI. If your company does not have ergonomically engineered hardware, software or furniture, then do something about it. It’s your health.
1 A copy of the survey is attached to the end of this paper. The correct answer is bolded.
i URL address : http://webreference.com/rsi.html#whatis
ii URL address : http://www.engr.unl.edu/ee/eeshop/rsi.html
iii URL address : http://www.micronite.com/
“Common Gateway Interface”. A standard protocol which allows HTML based forms to send field contents to a program on the Internet for processing. It also allows the receiving program to respond by sending an HTML response document.
“Electronic Mail”. An electronic document similar to a piece of mail in that it is sent from one person to another using addresses, and contains information. Email commonly contains information such as: sender name and computer address, list of recipient names and computer addresses, message subject, date and time composed, and message content. Sometimes, an Email message can have attached computer files such as pictures, programs, and data files.
A program or device which serves as an intelligent and secure router of network data packets. These mechanisms are configured to restrict the flow of packets in different directions (i.e. to and from the Internet) based on the system addresses (a.k.a. IP addresses) of the connected computers.
“File Transfer Protocol”. A program or feature popularly used over the Internet to transfer files between computers.
A person who deliberately breaks into computer systems for entertainment, gain, or spite. The most sophisticated hackers spend all of their time breaking into computers. The risk that these people pose is that they often steal or damage software systems and information.
A Web Page which is at the root of all Web Pages for a particular Web Site. A Home Page should portray the image that the company wants to project. Usually, these pages resemble marketing slicks, but with an interactive slant. This front page of a Web Site then provides hypertext links to the rest of the Web Site’s content and possibly to Home Pages for other related Web Sites.
“HyperText Markup Language”. A standardized programming language used to create hypertext documents. Used to create all Web Pages on the Internet. Also allows definition of data forms which communicate with CGI compatible programs on the Internet.
“HyperText Transfer Protocol”. A communications protocol used by Internet Web Service software to send Web Pages to Web Browser software over the Internet.
A type of text document which contains embedded “hotspots” which point to other sections of text or other documents. Any piece of text or graphic can be defined as a hotspot which points elsewhere.
(a.k.a. “The Information Superhighway”). A world-wide interconnection between thousands of computer networks on many different platforms, with over 10 million end users (and growing). The telecommunications backbone of the Internet is based on a network of U.S. government owned, national T3 lines. A growing number of Internet Providers are adding their own backbones.
A community of competing businesses which provide “on-ramps to the Internet”. The largest of these companies connect directly into the Internet backbone, or provide their own national or international backbones. Examples of true Internet Providers: Netcom, UUNet, CERFNet, SprintNet, and Spry. Examples of partial Internet Providers & partial Information Service Providers: CompuServe, Prodigy, and America On-Line.
“Internet Relay Chat”. A program or feature popularly used on the Internet by individuals to chat with others, by typing and watching text-based dialog. Many topic specific IRC channels have been created on the Internet by users. These channels form a sort of forum for conference room discussion.
A collection of forums which gather Email from Internet users about a specific subject. The collected Email entries (known as news articles) can then be perused by all Internet users. Some are simply for recreational discussions, while others may allow people to form self-supporting user groups.
“Pretty Good Privacy” encryption. A protocol for using private and public key encryption to secure Email and other Internet transactions.
“Transfer Control Protocol / Internet Protocol”. The network communication protocol used by all Internet computers. Similar in function to NetBIOS, SNA, or Novell Netware’s IPX/SPX.
A program or feature popularly used on the Internet by individuals to log into, and take control of other computers on the Internet.
“Virtual Reality Markup Language” A new emerging language becoming supported by the World Wide Web, for programming virtual reality content on the Internet.
A type of program used by individuals which reads HTML files on the Internet and presents them to the user in a friendly way and interactive way. Many such programs exist for many platforms. For UNIX several GUI browsers are popular. For those UNIX based terminals or DOS based PCs, Lynx provides a text interface to browse Web Pages. All Web Browsers allow the user to interactively jump from place to place by selecting hotspots (highlighted text or graphics). Some browsers allow the user to print page contents.
Web Page or Web Document
A single viewable unit of Web information. Often be comprised of an HTML file with several referenced graphics files. Generally, each Web Page has hypertext links to other Web Pages.
A collection of Web Pages built for or by a single company or individual. Usually provides one theme of content. A Web Site is not to be confused with a single physical location where a Web Server exists. It is a Cyber-Location.
A combination of computer hardware, telecomm. lines, and HTTP server software.
World Wide Web, WWW, or The Web
An intricate and vast web of information, tied together by hypertext links between multimedia documents residing on thousands of Internet computers around the globe.