Computer Studies Form 1 Notes : CHAPTER 3 – SAFE USE AND CARE OF COMPUTERS

CHAPTER 3

SAFE USE AND CARE OF COMPUTERS

This chapter helps the student become aware of the computer, its safety rules, and how to apply them. The safety rules to be observed concern personnel, materials, and equipment in the computer laboratory. The student is also expected to state correctly the safety precautions required in the lab and be able to identify possible causes of data loss and their precautions.

1. Behaviour in the Computer Lab
2. Handling of Materials and Equipment
3. Fire and Accidents
4. Chemicals and Combustible Materials
5. Ventilation in the Computer Lab
6. Safety Precautions and Practices
7. Possible Causes of Loss of Programs and Data
8. Precautions
9. Summary
10. Questions

BEHAVIOUR IN THE COMPUTER LAB

The computer lab forms a very important section of an organization or school; therefore, strict rules regarding the behaviour of personnel or students working or studying in the lab need to be established and adhered to.

One factor to consider is the cost involved in setting up the lab, including the cost of equipment. This should not be taken for granted, as damaged computers and peripherals can result in significant losses to the organization.

Cleanliness is a key factor in the lab. Personnel need to be clean while in the lab. Dust on hands or oil on fingers is not allowed. Foodstuffs are prohibited as broken pieces can get into peripherals such as keyboards and disk drives.

Depending on the floor covering, certain shoes may cause distractions by making noise, which can slow down work as attention shifts. External disks are not recommended in the lab as they may introduce viruses from outside sources.

Internal disks should not be allowed to leave the room. Strict procedures should be in place to monitor personnel who ignore this rule, as it may lead to data exposure to rivals or unauthorized users (“hackers”).

Any mechanical or technical faults should be reported immediately to technical personnel. Non-technical personnel should never attempt repairs.

It is important for every user to make routine backup copies of all work done in the lab to prevent data loss in case of disaster.

Proper procedures for shutting down and booting computers must be followed according to the operating system specifications to avoid disk damage and file fragmentation, which can cause delays in reading and writing data. Equipment should remain where installed and not be moved around the lab.

Changing peripherals between machines is discouraged. For example, a mouse assigned to one machine should remain there; if it malfunctions, technical personnel should be consulted.

HANDLING OF MATERIALS AND EQUIPMENT

Handling some materials and equipment in the lab should be restricted. For example, installation disks and special machines like servers should only be accessible to authorized personnel.

Computers and peripherals should always be handled with care since they contain delicate electronic parts that can break or become dislocated if dropped. It is recommended to use a trolley when moving equipment. No equipment should leave the lab without proper authorization.

Computer cables, if detached, should be properly reconnected to their respective machines. Technical operations should be performed only by qualified personnel to avoid further damage.

Disks should be protected from natural hazards such as excessive temperatures, water, dust, and magnets to maintain data integrity.

FIRE AND ACCIDENTS

Fire and other accidents, such as electrocution or slipping on wet floors, are possible in the lab.

Fire poses a significant threat to data and equipment. Labs should provide training on fire handling and have fire-fighting equipment like hand-held CO₂ and BCF extinguishers readily available.

Data should be stored in fireproof safes to prevent loss. Insuring equipment and software with insurance firms can provide compensation after such incidents.

CHEMICALS AND COMBUSTIBLE MATERIALS

Chemicals and combustible materials should be stored in designated areas. False floors and ceilings should be used to route pipes carrying chemicals like fluorocarbon fluid used for cooling mainframes.

Combustible materials such as fire extinguishers should be placed in visible locations but only used in emergencies. Harmful materials should be disposed of through properly located ducts.

VENTILATION IN THE COMPUTER LAB/WORKING AREA

Windows provide adequate ventilation but should not be too wide to prevent unauthorized entry. Additional ventilation should be small and placed high. Curtains should be used to maintain privacy.

SAFETY PRECAUTIONS AND PRACTICES

Cabling

Cables should be routed along false floors, ceilings, or walls to avoid interference and prevent accidental disconnections.

Stable Power Supply

A stable, adequate, and independent power supply is essential. Voltage fluctuations, sudden power cuts, and spikes can damage computer systems, disks, and processors, and cause data loss.

Large batteries, Uninterrupted Power Supply (UPS), and generators should be on standby to handle power crises.

Burglar Proofing

All lab doors should be burglar-proof to prevent unauthorized access and protect data and equipment.

Ventilation

Ventilation is necessary but should not allow unauthorized access to the lab.

Floor Space

The floor space should be wide enough for equipment movement and emergency exits. Slippery floors are not recommended; if present, they should be covered with mats.

VDU LEGISLATION

This British legislation passed in 1990 applies to frequent users of computer screens and states:

1. Do not use a computer for more than one hour continuously.
2. View the screen at an angle of 30°–60°, not directly.
3. Maintain a distance of 300mm–480mm from the screen.
4. Keep arms and elbows at right angles and parallel to the ground while using the keyboard.
5. Seats and desks should be adjustable to the user’s height to prevent Repetitive Strain Injuries (RSI). Seats should have backrests.
6. All seats should have castors for mobility and noise reduction.

Note: An anti-glare screen is recommended.

COMPUTER LAB DESIGN

Before discussing safety regulations, consider the factors involved in designing a computer room.

Constraints of Computer Room

The following requirements must be observed:

• Need for air conditioning
• Lab size and dimensions
• Cleanliness
• Equipment placement
• Accessibility for maintenance and media resupply
• Health and safety considerations
• Noise control

Air Conditioning

Air conditioning is essential in rooms housing mainframes or minicomputers. Many devices have built-in environmental controls such as fans and filters.

Air conditioning controls:

1. Temperature: should be between 18°C and 24°C.
2. Humidity: recommended between 45% and 55% to avoid moisture and electrostatic buildup.
3. Dust control: Disk media and processors require high cleanliness levels. Labs should have positive pressure, air locks, and sticky mats on floors.

Dimensions of the Lab

Lab size should consider:

• Equipment supplier requirements
• Operating conditions
• Future expansion needs

Ceiling height should accommodate false floors and ceilings for equipment load distribution, cable paths, and air ducts.

Accessibility

There must be clear routes for equipment installation and emergency exits. Corridors should be high enough with double doors, and floors, stairs, or lifts must support equipment weight. Ground floor locations are recommended but have security risks.

Reception areas should be spacious for trolley storage.

Equipment Placement

Equipment should be arranged to ensure efficient workflow and minimize walking distances between devices, such as placing printers near computers.

Health and Safety

• Lighting: Provide ample lighting to minimize reflections and glare, including emergency lighting.
• Alarms: Fire alarms must be audible and visible from all angles for quick response.
• Communications: Telephone lines should be strategically placed with visible indicators to reduce noise.
• Physical Security:

General:

• Only authorized personnel allowed in the computer room.
• No outside walls to deter intruders.
• Small windows for ventilation.
• Video cameras to monitor personnel and intruders.

• Fire: Fire alarms, automatic smoke detection, and hand-held CO₂ and BCF extinguishers should be installed. Personnel should receive evacuation training.
• Flooding: Labs should not be located in basements or near water pipes to avoid flood damage.
• Power: Independent, stable power supply with shrouded panic-off buttons is essential. Power issues include:

• Supply interruption: Caused by transformer failure, accidental line cuts, lightning, or inadvertent shutdowns.
• Spike: Voltage surges from interference sources that can cause data loss and disk corruption.
• Voltage frequency variation: Fluctuations that may disrupt networked computers.

Standby generators, large batteries, or UPS units should be available to maintain power during outages.

DUST/DAMP PROOF

Disk storage media and processors require high cleanliness and stable temperature to maintain data and power function.

Labs should have positive pressure, use suitable building materials to reduce dust, and special floor coverings to reduce dampness.

Lighting

Adequate lighting should minimize reflections and glare, with provisions for emergency lighting.

Standard Furniture

Furniture should be stable and firm, with enough legroom and clearance for posture changes. Desk surfaces should be spacious and glare-free. Chairs should be adjustable for different user heights.

Fire Fighting Equipment

Fire extinguishers such as hand-held BCF and CO₂ should always be available and visible. Staff should be trained in their use and safety precautions.

POSSIBLE CAUSES OF LOSS OF PROGRAMS AND DATA

Loss of programs and data results in loss of valuable information. Causes include:

Power Supply

Power supply problems occur in two forms:

• Power supply interruption: Caused by transformer failure, line cuts, accidents, lightning, or inadvertent shutdowns.
• Spike: Voltage surges from interference sources like switches and electromechanical devices.

These issues can damage disk heads, causing data loss, and corrupt disk files when power is removed suddenly. RAM loses data immediately when power is cut.

Virus

A virus is software that replicates itself without user knowledge. Viruses often spread via infected external disks or demonstrations by hardware/software engineers. Boot sector viruses infect disks by loading into memory when the disk is inserted.

Viruses can replicate, corrupt data, and modify stored information into unusable formats.

Accidental Erasure

Users may unintentionally erase data, for example, deleting a whole directory instead of a single file or mixing source and destination disks during copying, leading to data loss.

Crashing Disks

Disk heads can crash due to sudden power loss, making data unreadable and causing loss.

Poor Storage of Disks

Disks require high cleanliness. Dust clogs disk heads, impairing reading and writing. Storing disks in damp or excessively dry places damages their surfaces. Exposure to magnets can demagnetize disks, destroying stored data.

Unauthorized Access

Only authorized personnel should access the lab. Hackers may steal or tamper with data, or introduce viruses. Unauthorized users may commit fraud, such as altering invoices.

PRECAUTIONS

Precautions to prevent data loss include:

a) Power Failure

Precautions include:

Regular Saving of Documents/Files

Users should save work frequently, every 5 to 10 minutes. Some applications save automatically. Failure to save risks losing work during power interruptions.

Use of UPS

An Uninterrupted Power Supply (UPS) uses batteries to maintain power during outages. Its size depends on system capacity and required backup time. UPS systems can automatically save data and shut down safely upon power loss.

Use of Batteries and Generators

Standby generators and large batteries sustain computer operations in critical organizations like hospitals and military installations. Batteries maintain power until generators start.

Virus

Precautions include:

Write Protection Disks

Floppy disks have a physical write-protect tab that prevents writing or modification, protecting against viruses.

Restriction of Disk Movement

Strict procedures should prevent disks from leaving the lab. External disks should be scanned (“sheep dipped”) for viruses before use.

Disable Disk Drives

Physically removing disk drives after work hours prevents virus infection and accidental erasure. Only technical staff should perform this.

Anti Virus Software

Antivirus software helps disinfect disks and memory. It should be regularly updated. Examples include Norton Anti-virus, Dr. Solomon Anti-virus Toolkit, and F-Prot Professional.

Accidental Erasure

Recovery utilities can undelete files or unformat disks depending on the operating system and software. Backup copies should always be maintained. Heat-resistant safes protect backup disks from heat damage.

Crashing Disks

Using backup copies and observing power failure precautions help avoid data loss from disk crashes.

Poor Storage and Handling of Disks

Disks should be kept away from sunlight, water, dust, and magnets to preserve data integrity and readability.

Unauthorized Access

Access should be restricted to authorized personnel. Passwords and data encryption protect files from unauthorized access. Passwords should be changed regularly.

Data encryption involves writing information in a grid format decipherable only by authorized users. For example:

MEET ME TONIGHT AT 8 encrypted in a 5 x 4 grid becomes MMN.EEIAE.GTTTH..OT8.

LICENCED TO KILL encrypted similarly becomes LCOLIE..CDK.E.I.NTL.

Note: Words are written row-wise with spaces represented by dots. Reading is done column-wise.

SUMMARY

• Factors to consider when designing a computer lab include dimensions, accessibility, equipment placement, health and safety, lighting, power supply, physical security, and noise.
• Strict behavioural rules must be observed in the lab.
• Safety precautions include fire-fighting equipment, standard furniture, proper lighting, dust/damp-proofing, proper installations, stable power supply, and burglar-proof doors.
• Possible causes of data loss include power failure, viruses, accidental erasure, disk damage, poor storage, and unauthorized access.
• Precautions include using UPS, batteries, generators, antivirus software, write protection, movement restrictions, disabling disk drives, recovery utilities, backups, heat-resistant safes, proper disk storage, passwords, and encryption.

QUESTIONS

1. List factors to consider while designing a computer lab.
2. What points should be observed regarding the behaviour of personnel in the computer lab?
3. Discuss the importance of handling materials and equipment properly in the lab.
4. What safety precautions and practices should be implemented in a computer lab?
5. What are the possible causes of data loss in an organization?
6. List and discuss the factors to consider as recovery measures against data loss risks.