Health and safety - working with computers

GCSE Physical Education (Sport & Coaching)

HEALTH AND SAFETY AND ERGONOMICS

Introduction:

Many health problems can arise from working with computers. Articles appear regularly in the newspapers relating stories of employees who are suing their employers for computer-related illnesses. Whilst computers process data and perform calculations with complete accuracy, humans need food, rest and relaxation if they are to avoid headaches, stress, tired limbs and mistakes.

This report aims to be describe health and safety issues related to the installation of computing systems, and then will describe that how the study of ergonomics can improve the classroom environment, the last will evaluate the ergonomic elements incorporated in our computer classroom.

Main text:

Health and safety

Our desktop computer can cause more problems than ours know. Stress is often the cause of much work-related illness. Having too much to do in the time available, completing tasks, which are new to you and about which you are unsure, and sometimes not having enough to do, are all factors affecting stress at work.

In some organisations, computers are used to monitor the volume of work completed. The resulting stress can cause headaches, stomach ulcers and sleeplessness. In some work roles it can be difficult to get away from work; the use of mobile phones and laptop computers mean that you may be working ‘on the move’ whilst having a modem at home means you can easily take work home with you. Anyone catching the early train to London (called the Master Cutler) will have seen busy executives tapping away on their laptops with a mobile under their chins, rather than relaxing with a newspaper.

Computers have brought us so much information, and allow us to process it to suit our purposes. Many managers now suffer from information overload. There is just too much information too takes in.

All this can mean that work takes over your life, and personal relationships suffer. A survey of 500 heads of departments revealed that over three quarters of respondents had suffered from failing personal relationships, loss of appetite, addiction to work and potential alcohol abuse (Heathcote, 1998).

Repetitive strain injury (RSI)

RSI is the term used to describe several disorders affecting the neck, shoulders and upper limbs. The symptoms include aches and stiffness in arms, neck and shoulders and tingling or a loss of sensation in arms and hands.

Visual fatigue (eyestrain)

People who spend long hours in front of a computer screen are at risk of eyestrain caused by the glare from the screen, inadequate lighting, badly designed workstations and poor working practices. In addition, some workers do not wear the correct prescription glasses. A small spotlight focussed on the desktop can be helpful.

Symptoms include sore eyes, hazy vision, difficulty in focusing when switching vision between near and distant objects and aching behind the eyes. Specific causes are likely to be:

Screen glare
Poor character-definition on screen
Excessive periods of screen viewing and consequent short distance focusing
Screen flicker
Screen reflection
Insufficient or excessive lighting
Frequent, excessive eye movement when switching between screen and document

Body fatigue

I have already mentioned many elements of this earlier, when discussing the impact of stress. Tense, aching muscles or inflamed nerves in the shoulders, neck, back, wrists or hands may be caused by:

Poor seating position

Moving around to reach different parts of the workstation

Keyboard at wrong height - see earlier comments on RSI. Products are available to support wrists and so avoid injury.

Other hazards

The design and positioning of a workstation may prevent some hazards, which come from the use of computer equipment. Workers can be injured on sharp edges and corners, and when lifting heavy equipment. Badly wired equipment may give a worker an electric shock. The shock continues until contact with the machine is broken, or the power supply is disconnected. Safe maintenance of equipment is therefore very important, as these shocks are life threatening. Static electricity can also pose a hazard. Static can accumulate on the computer screen, and give the worker a shock if they touch the screen. Whilst injury is unlikely, it can cause damage to stored data. The problem is easily solved with anti-static wipes.

Extremely low frequency (ELF) radiation

Elf radiation is emitted from sunshine, fire, the earth’s magnetic field, as well as the manmade sources of computer monitors and electricity mains. It may be connected to some health problems, but so far the research evidence is inconclusive.

Computers, Health and the Law

The Health and Safety (Display Screen Equipment) Regulations 1992 requires employers to:

Perform an analysis of workstations in order to evaluate the safety and health conditions to which they give rise
Provide training to employees in the use of workstation components
Ensure employees take regular breaks or changes in activity
Provide regular eye tests for workstation users and pay for glasses
It also states that employees must:
Use workstations and equipment correctly, in accordance with training provided by employers
Bring problems to the attention of their employer immediately and co-operate in the correction of these problems

Prevention

Computer ...

This is a preview of the whole essay

The Health and Safety (Display Screen Equipment) Regulations 1992 requires employers to:

Perform an analysis of workstations in order to evaluate the safety and health conditions to which they give rise
Provide training to employees in the use of workstation components
Ensure employees take regular breaks or changes in activity
Provide regular eye tests for workstation users and pay for glasses
It also states that employees must:
Use workstations and equipment correctly, in accordance with training provided by employers
Bring problems to the attention of their employer immediately and co-operate in the correction of these problems

Prevention

Computer keyboard users can take several steps to lower their chances of developing RSI. Some of these centres around the configuration of the workplace, or "ergonomics." Others have to do with human factors.

(From class work&notes)

Ergonomics

Ergonomics can be defined as fitting the job to the worker. All workers are not the same size and everyone has limits. Ergonomics aims to design workstations, work processes, equipment, and tools to fit you. As a worker, it is important that you know how to adjust your office workstation to suit you.

Ergonomics has a wide application to everyday domestic situations, but there are even more significant implications for efficiency, productivity, safety and health in work settings. For example:

Designing equipment and systems including computers, so that they are easier to use and less likely to lead to errors in operation – particularly important tin high stress and safety-critical operations such as control rooms.
Designing tasks and jobs so that they are effective and take account of human needs such as rest breaks and sensible shift patterns, as well as other factors such as intrinsic rewards of work itself.
Designing equipment and work arrangements to improve working posture and ease the load on the body, thus reducing instances of Repetitive Strain Injury/Work Related Upper Limb Disorder.

If a job does not fit a worker, the workers are more likely is exposed to risk factors that may lead to musculoskeletal injury. The main ergonomic risk factors in the office include the following:

Repetition: tasks or body movement carried out over and over again.
Awkward postures: body positions that are not ‘ideal’ such as twisting your neck to view your monitor or reaching forward or to the side to use your mouse.
Static forces: holding positions for long periods of time (i.e. sitting, neck bent to read monitor, reaching to type).

Every person responds to ergonomic risk factors in different ways; for example, one worker may have symptoms of an injury while another worker performing the same tasks may not have symptoms. Ergonomic risk factors should be identified and reduced to lower the risk of injury.

Ideal Computer Workstation

Many people spend thousands and thousands of dollars on their computers, software, and games and then completely disregard the workstation where they sit day in and day out. But that would be like buying a Ferrari and then buying the cheapest tires possible! It just won’t work in the long run and it’s the person who’s going to end up hurting, literally.

Furniture and Equipment

Stable work surface. One that is adjustable in height may be good to have when adults and very young children are sharing the same workstation.

Comfortable, ergonomic, adjustable chair with at least chair height and back support adjustment mechanisms. If the back tension of the chair does not adjust, make sure that the lower back is firmly supported. Armrests that pivot and are height and width adjustable are also a good idea. Remember that while most adjustable features are not absolutely essential, they do assure that many people of different sizes will feel comfortable in the chair.

Height-adjustable, negative slope keyboard tray is best for keeping the elbows at a >90 degrees and for allowing the wrists to remain in a neutral position.
Note: Desktop keyboards and those placed on (those on a positive slope) do not fully allow the elbows and wrists to remain in neutral posture and actually encourage wrist extension.
Height-adjustable, gliding mouse platform that allows the mouse to be positioned close to the side of the body, above the keyboard tray (so that the arm does not have to reach to the side).
It does not matter exactly what type of keyboard and pointing device you use as long as whatever you use feels comfortable, fits your hands, and allows you to work in a neutral hand and body posture

Normal Work Area

The normal work area corresponds to the space and objects that can be reached by a person while sitting in front of a computer, without having to twist the body or reach far. Make sure that everything you need is within this area, including books, documents, tools, a telephone, etc.

Be sure that the desk has a surface large enough to support all of your materials, even the ones that you are not currently using.

If typing from a book or document, make sure that it is placed in a document holder that is placed near the screen, in order to avoid head twisting.

The body should be cantered on the alphanumeric part of the keyboard. Most keyboards are asymmetrical in design (the alphanumeric keyboard is to the left and a numeric keypad to the right). If the outer edges of the keyboard are used as landmarks for centring the keyboard and monitor, the user’s hands will be deviated because the alphanumeric keys will be to the left of the user's midline.

Computer Monitor Position

Monitor that is height and angle adjustable works best.

Monitor should be placed directly in front of the user and facing the user, not angled to the left or right (to discourage neck twisting).

Your eyes should be in line with a point on the screen that is 2 to 3 inches below the top of the monitor. If the monitor is above or below this height, your neck will be raised or lowered and the result will be neck pain.

Monitor should be at a comfortable distance for viewing, which is usually around an arm’s length (sit back, raise your arm, and your fingers should touch the screen)

If text on the screen is too small, increase the font size, do not move monitor closer.

Users with bifocal glasses should tilt their monitors slightly backwards.

Lighting

It should not be too bright or too dark. Always use light even though a computer screen is self-illuminating, there should not be a large contrast between the screen and the area surrounding it.

Indirect lighting (that which illuminates the walls and ceilings), in combination with a task light, works best.

If you do use a task light, position it as far away as possible and make sure that you cannot see the light source when you look at the screen.

There should be no glare falling on the screen. If there is, reposition the workstation with regard to the light sources (natural or artificial). Be careful not to just move the monitor, resulting in a poor viewing angle. If repositioning alone does not work, use a good quality glass anti-glare screen. If left uncorrected, glare will cause discomfort, eyestrain, and headaches.

Avoid very glossy work surfaces and furnishings, such as mirrors and shiny metal, which will contribute to glare.

Noise and Ventilation

Work in an environment with a level of noise that is comfortable for you. Working in an uncomfortably loud environment stresses the body and, as a result, the muscles tense up. This tension accelerates injury.

If using headphones make sure they are at a comfortable noise level and that they fit properly.

Workstation should be located in a well-ventilated area, with adequate heating and cooling in order to minimize discomfort.

The right workstation

Table height.

To adjust the chair properly, look first at the height of the table or desk surface on which your keyboard rests. On the average, a height of 27-29 inches above the floor is recommended. Taller people will prefer slightly higher tables than do shorter people. If you can adjust your table, set your waist angle (see below) at 90 degrees, then adjust your table so that your elbow makes a 90-degree angle when your hands are on the keyboard.

Wrist angle

If your keyboard is positioned properly your wrists should be able to rest comfortably on the table in front of it. Some keyboards are so "thick" that they require you to bend your hands uncomfortably upward to reach the keys. If so, it will help to place a raised wrist rest on the table in front of the keyboard. A keyboard that requires you to bend your wrists is a common cause of CTS among computer users.

Elbow angle

With your hands resting comfortably at the keyboard and your upper arms vertical, measure the angle between your forearm and your upper arm (the elbow angle). If it is less than 90 degrees, raise the seat of your chair. If the angle is greater than 90 degrees, lower the seat. Try to hold your elbows close to your sides to help minimize "ulnar displacement" the sideways bending of the wrist (as when reaching for the "Z" key).

Waist angle

With your elbow angle at 90 degrees, measure the angle between your upper legs and your spine (the waist angle). This too should be about 90 degrees. If it is less than 90 degrees, your chair may be too low (and your knees too high). Otherwise, you may need to alter the position of the backrest or adjust your own posture (nothing provides better support than sitting up straight). (Note: If making your waist angle 90 degrees changes your elbow angle, you may need to readjust the height of your chair or table.)

Feet

With your elbows and waist at 90 degree angles, your feet should rest comfortably flat on the floor. If they don't, adjust your chair and table height and repeat the steps above. If your table isn't adjustable and your feet don't comfortably reach the floor, a raised footrest can help. Otherwise, you may need a different table.

Work Routine

You need very little recovery time between keystrokes to cool and lubricate the flexor tendons. If you type constantly, however, the need for recovery builds. Further, working with your hands bent upward at the wrists or frequently bending your wrists sideways heightens the friction within the carpal tunnel. It takes longer to recover from these motions. Working under stress (deadline pressure, anger, or other anxiety) can make matters even worse.

Many studies recommend a 10-15 minute break each hour to give yourself the recovery time you need. This needn't be a break from productive activities just a break from your keyboard. Exercises can help, too. Try the following:

Make tight fists, hold for one second, and then stretch your fingers out wide and hold for five seconds. Repeat several times.
With arms outstretched in front of you, raise and lower your hands several times. Rotate your hands ten times (make circles in the air with the fingertips).

Variety is the key. RSI occurs most frequently in workers whose motions are not only repetitious but are kept up for hours at a time. If you use a keyboard, structure your workdays to include a mix of activities each hour. For example, instead of typing all morning and filing all afternoon, mix typing and filing throughout the day.

(Source: )

Screen display

In workstation design, the screen display has to be judged for its quality and position in relation to the operator. Screen quality is measured for the clarity and steadiness of the images it displays. A high-resolution screen is best, even for word processing work, but is vital for design work. Precautions to minimise eyestrain include:

Appropriate lighting. It is usually necessary to supplement natural light with artificial light, and control bright sunlight using blinds.

Use of high-resolution screen

Correct adjustment of contrast and brightness controls.

The screen should be positioned for optimum viewing range and located to avoid excess head and eye movement (see diagram above).

Cables and floors

Loose cable trailing beneath desks and across floors can cause workers to trip and fall. Cabling should be laid through specially designed channels. Carpeting should be chosen to produce a quieter working environment, but be smooth enough for workers to be able to move their chairs around easily. If carpets are made from man-made fibres, then anti-static mats should be used to cover areas around workstations.

(From class work&notes)

Most popular ergonomic product

Ergonomic chairs: As long as the chair has at least height and back adjustment features, it will be worth your while. These chairs can range in price from a hundred dollars or less to more than a thousand dollars, and generally the more expensive ones have more adjustment features and better construction. The greater a chair’s adjustment capabilities, the greater the number of people that will be able to sit on it comfortably.

Armrests: The best armrests will allow you to rest the area of your forearm that lies halfway between your wrist and elbow, without compressing any part of the arm. Look for those with at least height and width adjustment features. Research studies have shown that armrests provide many benefits, such as:

Reduced postural strain to the upper body

Reduced muscle loads in the upper arms, shoulders, and neck

Reduced loads on the spine (by redistributing the weight of your upper body)

Reduced forearm exhaustion while typing (when your forearm gets tired, you tend to increase wrist extension)

Reduced key forces while typing (the amount of force with which you hit the keys plays a role in CTD development)

Keyboards: Most ergonomic keyboards on the market today are split keyboards (those where the alphanumeric keys are split at an angle). These keyboards mainly address the problem of wrist ulnar deviation (side-to-side). However, wrist extension and flexion (vertical movement) are more important when preventing injury. There is no consistent research that shows that split keyboards offer any postural benefits-, and for most people a regular keyboard design works just fine if it's placed in the proper neutral position. Some people find split keyboards to be more comfortable than traditional keyboards, so if you use one, make sure that it is not causing your shoulders to abduct (raised higher than is comfortable).

Keyboard Trays: Height-adjustable, negative slope keyboard trays (those that height adjust down to your lap and allow you to tilt them away from your body) function best because they allow the body and hands to maintain the most neutral working position (see section on Neutral Keyboarding Posture). In order to be in the proper position, you should almost feel as if your keyboard is placed on your lap.

Pointing Devices: There is no conclusive research that says that one type of pointing device (mouse, trackball, stylus, touch pad, joystick, etc.) is better for you than another. Just make sure that when you use whichever one you choose, you are using it in a neutral position (arm relaxed, close to your body). A pointing device should also fit the hand of its user. Don’t use a very large mouse if you have very small hands. In the same token, young children often prefer trackballs because the traditional mouse design is sometimes too big for their small hands.

Mouse: The mouse is the most popular type of pointing device and there are many types of “ergonomic” mouse out there. Before you purchase a mouse, place your hand over it. If it causes your wrist to extend up too much, then it’s not really “ergonomic.” One recent study showed that one particular mouse design, which is flatter and broader than a traditional mouse, could reduce side-to-side wrist deviation.

Wrist rests: Research studies haven't demonstrated any substantial benefits for wrist rests. Some people may actually experience increased pressure in the wrist area just from using one. If you do choose to use a wrist rest, a broad, flat surface design works best. Many keyboards come with an attached or built-in plastic wrist rest, which works well if it is broad and flat. Avoid soft and squishy wrist rests (gel-filled) because these will contour to your wrist and encourage wrist-twisting movements and your hands should be able to glide over the surface of a wrist rest during typing. Using a wrist rest as forearm support can be comfortable and effective.

Glare Screens: Glare screens can only reduce glare so a lot of people think that they can reduce or eliminate magnetic fields. This is simply not true, no matter what the packaging says. Any jargon on the packaging about “fields” usually refers to static electricity. Usually it is the higher quality glare screens that are worth getting. The lesser quality ones may reduce glare but may also accumulate a lot of dust, thereby obscuring the image. And remember that you may not even need a glare screen if you position your monitor in a way that does not encourage glare (refer to Lighting within Ideal Computer Workstation section).

Support Braces/Gloves: There is no consistent research evidence that wearing wrist supports during computer use actually helps reduce the risk of injury. If you do like wearing a wrist support, make sure that it keeps your hand flat and straight, not bent upwards. There is some evidence that wearing wrist supports at night in bed can help relieve symptoms for those with Carpal Tunnel Syndrome.

Conclusion:

From the in formation above I thing ergonomic is a very good way too help us keep our health and safety, I recognise that our workstation is quite useful place. Example the light, is not too bright and not too dark, also our chairs, we could change the best position for ourselves, but the temperature is a little bit higher, so the user may not fill confidence, so the exercise is really necessary for us, fowling points are useful exercise in the classroom:

Deep Breathing: Breathe in slowly through the nose. Hold for 2 seconds, and then exhale through the mouth. Repeat several times.
Head and Neck: Turn head slowly from one side to the other, holding each turn for 3 seconds. Repeat several times.
Shoulders: Roll shoulders slowly in a circular fashion, while trying to make the circle as big as possible. Take about 5 seconds to complete one circle. Repeat several times.
Wrists: Hold your hands out in front of you. Slowly raise and lower your hands to stretch the muscles in the forearm. Repeat several times.
Fingers and Hands: Make a tight fist. Hold for a second. Then spread your fingers apart as far as you can. Hold for 5 seconds, then relax. Repeat several times.