4.4 Given a scenario, use common safety procedures

  • Electrostatic Discharge (ESD)
  • ESD Mats
  • Equipment Grounding
  • Proper Power Handling
  • Proper Component Handling and Storage
  • Antistatic Bags
  • Compliance with Government Regulations
  • Personal Safety
    • Disconnect Power Before Repairing PC
    • Lifting Techniques
    • Electrical Fire Safety
    • Safety Goggles
    • Air Filtration Mask

Equipment Grounding

When we construct a building, the electricians install a “grounding rod”, which is a long rod metal rod that is hammered deep into the ground.  Electrical outlets throughout the entire electrical system are connected to the grounding rod through a ground wire.  That’s why it is called a ground.  Electricity always tries to escape into the ground.  It doesn’t like to stay trapped in the wires.

Most appliances contain a third prong, which is connected to the ground wire.  If there is a fault in the wiring, a lightning strike, or some other electrical issue, the electricity flows into the ground wire, and literally into the ground.  This protects us against electric shocks and fire.

Some devices contain additional grounding requirements.  You will see a ground symbol on the chassis.

If you see this symbol, you should connect the ground lug on the device to the building ground.

In a server room, an electrician will typically install a grounding bar

  • The bar allows us to attach multiple grounding wires

  • Grounding wire is usually copper, with a green plastic coating
  • The thickness of the wire depends on the amount of equipment connected and the amount of current that is expected to flow through the wire.  According to most building codes, the minimum diameter is #6.

  • Since the ground wire is connected to the ground, in theory, it is always safe to touch it.  Do not touch it.  Nobody ever inspects the ground wire to make sure it is going where it is supposed to be going.  If the ground wire is broken somewhere and a power surge travels through it while you are touching it, you will be cooked like crispy chicken.

Server racks and cable trays should always be grounded.  That is a requirement in most electrical codes.

  • If the rack has a ground symbol, connect the ground wire to that

  • If the rack doesn’t have a ground symbol, connect the ground wire to a hole on the rack.  Scrape the paint off the rack first, so that the ground wire contacts the bare metal of the rack.

Proper component handling and storage

Some electronic devices (hard drives, PCI cards, etc.) can be damaged by electric shocks or static electricity.  These devices should be stored inside antistatic bags.  Bags are available in a wide variety of sizes.

When you walk, your body builds up static electricity.  When you touch an electronic device, you may transfer some of that electricity into the device.  This is known as an electrostatic discharge.  The discharge is bad. 

Wear an ESD wrist strap when you are working with sensitive electronic components.  The strap takes static electricity from you and passes it to the ground.  You must connect the other end of the strap to a ground source.

An ESD mat transfers static electricity to the ground.  The ESD mat allows you to work on a cellular phone or other computer equipment without the risk of shocking it.  The mat may also allow you to connect a wrist strap.

You can also self ground yourself before working with computer equipment.  Self-ground by touching something metal.  The metal will absorb any static in your body.

Personal Safety

Some personal safety tips

  • Always disconnect the power before repairing any electronic device

    • Some devices have redundant power supplies (multiple electrical plugs).  Make sure that you disconnect all of them.

    • Some devices have built in batteries in addition to electrical supplies, which should be disconnected.

    • Devices may contain capacitors, which could create electric shocks even after the battery and power supplies have been disconnected.  Be cautious not to touch any capacitors.

    • An exception can be made for hot-swappable components (such as replacing a hard disk drive on a server).

  • Remove jewelry before repairing a device

    • The jewelry could get caught and cause personal injury

    • The jewelry could conduct electricity

  • Lifting Techniques

    • Follow proper lifting techniques

    • Lift with your legs, not your back

    • Have good posture

    • Don’t twist

    • Go slowly

    • If you’re carrying something, make sure that there are no obstructions in the path ahead of you

  • Weight Limitations

    • Don’t lift more than you can handle

    • Ask for help or use a tool such as a dolly or cart

  • Electrical Fire Safety

    • Inspect power cords and outlets to make sure that they are not damaged before using them

    • Use three-pronged electrical cords with equipment, because they provide grounding

    • Keep an electrical fire-rated fire extinguisher nearby

  • Cable Management

    • Cables should be neat and labelled

    • Proper cable management should start when equipment is installed

    • Tangled cables are difficult to trace and can present a tripping hazard

  • Safety Goggles

    • Wear them

    • Your eyes are sensitive and it’s impossible to predict when harm to them could occur

    • The tiniest spec of metal or loose wire could come out of nowhere, and cause blindness

  • Air Filter Mask

    • An air filter may also be known as a respirator.  It protects you from harmful fumes, gases, and other contaminants.

    • Wear one when required.

    • Make sure to use the correct filter for the hazard you encounter (there are different filter types for different hazards).
  • Other types of Personal Protective Equipment

    • You may need to wear other types of personal protective equipment depending on the hazard that you encounter

    • This could include steel toed boots, gloves, a hard hat, a reflective vest, and/or long-sleeved shirts

  • Safety Regulation

    • Follow the safety regulations that are established by your organization and by the jurisdiction where you operate
    • It is your legal right to refuse unsafe work