220-1102 Question 707
Single answerESD matsA technician is replacing the motherboard in a desktop PC on a workbench that has an ESD mat installed. Before opening the antistatic bag and handling the new board, the technician wants to set up the workspace correctly to reduce the risk of electrostatic discharge. Which action should the technician take FIRST?
- A
Connect the ESD mat's grounding cord to a known-good ground point and clip the wrist strap to the mat or common grounding point
- B
Place the new motherboard on top of the antistatic bag so the bag can insulate it from static
- C
Spray the ESD mat with a household cleaner to improve conductivity before touching components
- D
Plug the computer into a surge protector so the chassis is grounded while the system remains powered off
Show answer and explanation
Correct answer: A
Explanation
The key concept is that an ESD mat must be properly grounded to function as part of an effective electrostatic discharge control setup. In real-world PC repair, the technician should establish a common ground between the mat, wrist strap, and a verified grounding point before opening antistatic packaging or touching components. This aligns with standard ESD control practices used in electronics service environments and reflected in CompTIA A+ objectives on proper safety and handling procedures. Additional best practices include keeping components in antistatic packaging until needed, avoiding use of the bag itself as a work surface, and following the manufacturer's instructions for cleaning and maintaining ESD mats and straps.
- A. Correct.
Correct. An ESD mat is effective only when it is properly grounded. Best practice is to connect the mat to a known-good ground and use a wrist strap attached to the same common grounding point or directly to the mat if designed for that purpose. This equalizes electrical potential between the technician, mat, and components, reducing the chance of ESD damage while handling sensitive parts such as motherboards.
- B. Incorrect.
Incorrect. Antistatic bags are intended for storage and transport, not as a work surface. In many cases, the outside of an antistatic bag is conductive or dissipative, so placing a motherboard on top of the bag during service is not recommended. This is a common misconception because people assume the bag is safe in every way simply because it is used for ESD protection.
- C. Incorrect.
Incorrect. Household cleaners are not appropriate for ESD mats and may leave residues or damage the mat's dissipative properties. ESD-safe cleaning products should be used only according to the manufacturer's guidance. The misconception here is that increasing surface moisture or using any cleaner will improve static protection, but improper chemicals can make the setup less reliable.
- D. Incorrect.
Incorrect. A surge protector does not make this the correct first step, and the computer should not be relied on as the primary grounding method for the ESD workstation. In practice, the system should be powered down and disconnected before hardware service, and the mat should be connected to a known-good ground point. This option is plausible because technicians often associate grounded electrical equipment with ESD safety, but it does not replace proper ESD mat grounding.