UNIT 4 Safe, Secure and Ethical Use of computers
Key Unit Competency
By the end of this chapter, you should be able to maintain a computer in good working condition and use it safely, securely and ethically.
Learning Objectives
Knowledge and understanding
By the end of this chapter, you should be able to identify and follow the basic safety guidelines to prevent cuts, burns, electrical shocks, and damage to eyesight, when using computers.
Skills
By the end of this chapter, you should be able to observe and apply the correct safety and security procedures when using ICT.
Attitudes and values
By the end of this chapter, you should be able to:
(i) Appreciate and follow the basic safety guidelines to prevent cuts, burns, electrical shock, and damage to eyesight when using computers.
(ii) Show concern about computer vulnerability
Keywords in the chapter
• Ergonomics • Brushes and swabs • Fire extinguisher • Cleaning agent • Blower • UPS • Computer laboratory • Vacuum cleaner
Safe Lab Procedure
A computer laboratory, simply known as a computer lab, is a special room set aside for safe installation and use of computer equipment. It is used in learning institutions to enable efficient teaching and learning activities.
Safety Precautions and Practices in a Computer Laboratory
Computers are expensive to acquire. They are also delicate and must, therefore, be handled with utmost care. It is for this reason that certain rules, precautions, and
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practices MUST be observed when handling the computer and its components. This would help to avoid damage to the computers, injury to the user, as well as provide a conducive environment for teaching and learning.
Some safety precautions and practices are discussed below:
General safety
(i) DO NOT run in and out of the computer lab. This may cause one to knock down computer equipment hence causing damage.
(ii) Always cover the computers with dust covers after use to avoid dust accumulation on the machines.
(iii) DO NOT carry food or drinks to the computer lab. This is because spilling food or drinks on computer parts can cause damage.
(iv) Reinforce the entry points to the computer lab by use of padlocks, burglar proof doors, and metallic grills to ensure proper security of computer resources.
(v) Ensure that the computer lab is well ventilated to ensure the right amount of temperature and humidity.
(vi) Always shut down the computer using the correct procedure. This is because improper shutting down of a computer can lead to either data loss or crashing of the hard disk. Crashing of the hard disk refers to the permanent damage of the read and write head of the hard disk.
The following is the correct procedure for shutting down a computer. e following are some of the general safety precautions and practices:
(a) Close all open files and folders.
(b) Select the Start button and select Shut down.
(c) The shut down procedure automatically starts.
(d) Switch off the monitor.
(vii) Always consult the teacher or the technician before performing technical operations.
(viii) Ensure that all the cables in the computer laboratory are laid along the walls. They should not hang loosely since one may stumble, fall, and get hurt. If the cables are hanging loosely report to the teacher or the technician.
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Health safety
The following are some of the health safety precautions to be observed:
(i) The screen resolution should be properly adjusted and where necessary use antiglare screens to prevent eye strain.
(ii) Use ergonomics chairs, tables, keyboards and mice among others to ensure good posture.
(iii) Ensure there is proper ventilation in the computer lab to ensure good health of the user. (iv) Always take a break to prevent fatigue or repetitive strain injury.
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Electrical safety
The following are some of the electrical safety precautions to be observed:
(i) Follow proper guidelines when dealing with power supplies and Cathode Ray Tube (CRT) monitors. They contain high voltage that can lead to injuries and electrical fires.
(ii) Do not attempt to repair power supplies or CRT monitors. Always alert the teacher or the laboratory technician.
(iii) Always connect computers using Uninterruptible Power Supply (UPS). This protects them against damage by power instability.
Fire safety
The following are some of the fire safety precautions to be observed:(i) Ensure that the computer lab is equipped with fire extinguishers that are regularly serviced.
(ii) Ensure that the computer lab has an exit door for use in case of emergency or fire outbreak.
(iii) Ensure that the computer lab has fire or smoke detectors and alarms for warning in case of fire outbreak.
(iv) Do not smoke in the computer laboratory. Remember that cigarette smoking is harmful to your health. It causes cancer to various body organs. It also causes ailments of the circulatory and respiratory systems. It may also lead to unnecessary fire accidents.
Proper use of cleaning tools and fire extinguishers
Cleaning Cloth: A lint-free cloth is used to clean components such as the case drives, mouse, and keyboard because they do not leave residue and will not scratch plastic surfaces. Do not use a cloth to clean any circuitry such as the motherboard and RAM.
Brushes and Swabs: Soft-bristled brushes and swabs that are lint-free are used to dust off the hard-to-reach areas and to wipe stains from electrical contacts.
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Blower: It is a portable electric device used to remove dust and dirt from computers. Blowing is done by forcing compressed air through various internal parts of the computer. Always ensure that all doors and windows are open to avoid dust accumulation.
Portable vacuum cleaner: It is a device used for sucking dust, dirt, hair, and other particles when cleaning the computer lab floor and other surfaces as well. There are wet and dry vacuum cleaners that can be used to clean up wet or liquid spills.
Non-static vacuum cleaner: This is a small, hand-held vacuum cleaner that is designed specifically for use on computers to suck up dirt and dust loosened by brush or canned air. It is advisable not to use the household vacuum cleaner. It creates static electricity that can damage the computer
.Canned Air: Canned air is also known as gas duster or compressed air. It is used to loosen dirt and dust from delicate computer components.
The following are some of the safety precautions when using canned air:
(i) Do not shake the container because it can explode.
(ii) Always keep the liquid canned air upright. Turning the can upside down or tilting causes the liquid to spill and this can cause irreparable damage to the computer components that it touches.
(iii) Avoid inhaling canned air because it can lead to death.
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Fire Extinguisher
It is a metallic cylinder usually red in colour. It contains a substance that puts out a small fire. The agent is represented by a colour band, for example, black for carbon (IV) oxide, red for water, and blue for dry powder among others.
The computer laboratory MUST be fitted with gaseous fire extinguishers filled with carbon (IV) oxide to be used in case of fire outbreak. Water-based or powder extinguishers should be avoided because water contains ions which complete an electrical circuit resulting in electric shock. Powder extinguishers, on the other hand, can clog the computer parts thus causing malfunctioning.
Note: It is advisable to refer to instructions that come with each fire extinguisher before use.
To use a fire extingusher, do the following.
(a) Pull the pin. This will allow one to discharge the extinguisher.
(b) Aim at the base of the fire.
(c) Squeeze the top handle or lever to release the pressurised extinguishing agent in the extinguisher. (d) Sweep from side to side until the fire is completely extinguished.
Maintaining your Computer
(i) General precautions
• Computers should be connected to the UPS or plugged into a quality surge protector.
• Ensure the anti-virus software is updated regularly. Always scan the computer and the external storage devices before use.
• Always shut down the computer using the correct procedure.
• Avoid placing computers and related components at the edge of the table where they are likely to fall
. • Laptops should be carried in a bag with padding for protection.
• Engage the services of a reputable insurance company to cover the risk in case of loss or damage.
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(ii) Power connectivity
• Ensure there are enough sockets in the computer lab to prevent overloading.
• Connect the power cable from the main power source to the UPS and to the power supply unit on the computer.
• Correctly turn off the computer when not in use. Always remember to switch off the main power source
. • Install a standby generator that can automatically be used incase of power failure.
(iii) Precautions for connecting the mouse, keyboard and other external peripherals
• Connect the peripheral devices to the correct ports, for example, the USB or PS/2 ports for the keyboard and the mouse.
• Do not force peripheral devices into the ports to avoid bending the pins as this can lead to malfunctioning.
• Ensure that monitors are correctly connected.
Maintenance precautions
(i) System unit
• Switch off the computer system and unplug the power cable before removing the system unit cover.
• Use a damp lint-free cloth to clean the outer part of the system unit.
• Avoid using water to clean the internal components to prevent rusting. It is advisable to use a blower or a non-static vacuum cleaner.
(ii) Monitor
• Never spray cleaners directly onto the screen. Instead, use a lint-free cloth dampened with a recommended cleaner to wipe the screen. Use a clean cloth to dry off the screen
. • Clean the outside of the monitor with a recommended cleaning solution.
• Avoid pressing too hard on the screen when cleaning an LCD screen.
• Avoid cleaning the inside of the monitor. Always consult an experienced technician.
(iii) Keyboard
• Do not punch down keys with excessive force since this may damage the components underneath.
• Wipe the outside parts with a dampened lint-free cloth. Be careful to avoid dripping cleaning liquids onto or into the keyboard. If necessary, use a recommended cleaning solution to remove tough dirt. Always make sure that the keyboard is disconnected from the computer.
• Do not remove the keys but instead use canned air and a soft-bristled brush to clean hard-to-reach areas.
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(iv) Mouse
• Use a damp lint-free cloth to clean the extenal part of the mouse.
Assignment 4.1
1. List three general precautions applied on a keyboard.
2. State two health safety practices applied in a computer laboratory.
3. Give three fire safety measures practiced in a computer laboratory.
4. State any three cleaning tools used in a computer laboratory.
5. What are some of the electrical safety measures taken when working in a computer laboratory.
Learning Activity 4A
(i) In pairs, practise how to clean a computer monitor using a recommended cleaning solution.
(ii) In groups, discuss the general precautions carried out in the school computer lab.
(iii) In pairs, demonstrate the general safety measures taken in the computer laboratory.
(iv) Compare safety precautions observed in the chemistry laboratory with those observed in the computer laboratory.
(v) In groups, practise power connectivity precautions taken when connecting computers.
Revision Exercise 4
1. Describe the correct posture to take when working on a computer
. 2. State five general safety precautions practised in a computer lab.
3. Explain the reason for the use of lint-free swabs to clean the computer keyboard.
4. Explain three ways of maintaining a computer monitor
. 5. Explain why non-static vacuum cleaners are recommended to be used in a computer lab.
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