Publishers of technology books, eBooks, and videos for creative people

Home > Articles > Web Design & Development > Best Practices

Shockproof Guide to Working Safely on Your Mac

Whether the computers you're taking care of belong to you, a customer, or a large group, this sample chapter provides the information you need to approach any situation safely and with the proper tools. In this one-hour lesson, you'll learn about the risks to you and the computer when you service computers, as well as general maintenance tasks you might perform during the "verify repair" step in the Apple General Troubleshooting Flowchart. While these may seem like unrelated topics, safe workstations and conscientious work practices are all part of keeping computers, customers, and yourself happy.
This chapter is from the book


This lesson takes approximately 1 hour to complete.


Practice ESD damage prevention

List the basic equipment needed to reduce the risk of damage from ESD and explain how this equipment works

Set up a conductive workbench mat

Identify the risks of working with CRTs

Locate CRT safety, discharge, and disposal procedures

State the eight CRT safety rules

Discharge a CRT using Apple-recommended procedures

Explain safety and first-aid procedures related to the leaking of liquid coolant

Describe the hazards of working with an iMac power supply

Describe the risks of booting into EFI

Care for the translucent plastics on Apple products

Clean and maintain a monitor screen

Back up files

Check for viruses

Dispose of batteries safely

Optimize a hard disk

Whether the computers you’re taking care of belong to you, a customer, or a large group, this lesson provides the information you need to approach any situation safely and with the proper tools.

In this lesson, you will learn about the risks to you and the computer when you service computers, as well as general maintenance tasks you might perform during the “verify repair” step in the Apple General Troubleshooting Flowchart. While these may seem like unrelated topics, safe workstations and conscientious work practices are all part of keeping computers, customers, and yourself happy.

ESD Prevention

Whenever you open a Macintosh or other electrical device, you are exposing its internal components to potential damage from the static electricity that builds up in your body through normal activity. Electrostatic discharge (ESD) occurs when static electricity is discharged from one conductor (such as your finger) to another conductor (such as a memory chip) of a different potential. Exposing an integrated circuit (IC) to as little as 10 volts of static electricity can damage the IC irreparably—and you wouldn’t even know it happened, because humans can’t perceive static electricity less than 1500 volts. When you do feel an electrical shock, you are feeling a minimum of 3000 volts.

Since imperceptible ESD can damage ICs found in computer and communications equipment, you must be particularly careful when working on Macintosh hardware. Plastics, utensils, polystyrene products, polyester clothing, and even the ungrounded touch of your hand carry sufficient electrostatic charges to damage electronic components, even if you don’t feel a spark. This section provides guidelines for preventing ESD damage and describes how to set up an ESD-compliant workstation.

ESD Safety Guidelines

Follow these guidelines to reduce the risk of ESD damage:

  • Before working on any device containing a printed circuit, ground yourself and the equipment you are working on to an earth or building ground. Use a grounded conductive workbench mat and a grounding wrist strap or heel strap, and ground the equipment to the mat.
  • Handle all ICs by the body, not by the pins. Do not touch the edge connectors, exposed circuitry, or printed circuits on boards or cards. Handle ICs, boards, and cards by the edges, or extract them using an ESD-compliant pair of pliers or other appropriate tool.
  • Never place components on any metal surface. Metal surfaces can hold a static charge that will damage sensitive electronic parts. Use antistatic, conductive, or foam rubber mats.
  • Do not touch anyone who is working on ICs. If you touch someone who is properly grounded, your “zap,” or body charge, might cause damage. Always keep your own body charge away from other technicians.
  • Use static-shielding storage bags for boards and ICs. Before you leave your bench to take a board to a storage place, put the board in a static-shielding bag. Leave all Apple replacement modules in their ESD-compliant packaging until you need them.
  • Don’t wear polyester clothing or bring plastic, vinyl, or Styrofoam into the work environment. The electrostatic field that surrounds these non-conductors cannot be totally removed without the use of an ionized air generator.
  • If possible, keep the humidity in the service area between 70 and 90 percent, and use an ionized air generator if available. Charge levels are reduced (but not eliminated) in high-humidity environments. Using an ionized air generator helps neutralize the charge surrounding nonconductors. However, this type of device can’t provide total protection: the static charges often cause ESD damage before the neutralizing process eliminates the charge.

Workstation Setup

Before you start to work on any task involving circuit boards, you must verify that your workstation is ESD-compliant—that is, that it has equipment and materials designed to prevent ESD damage.

You need the following equipment to set up an ESD-compliant workstation:

  • A conductive workbench mat and wire lead—When properly grounded, the workbench mat provides a safe place on which to set sensitive components and equipment.
  • A wrist strap with a built-in 1-megohm resistor and wire lead—The wrist strap grounds you so that you can touch sensitive components without zapping them.
  • An equipment wire lead with alligator clips—This wire lead grounds the equipment so that an electrostatic charge cannot build up. It is especially important when you are working on CRTs, which can build up an electrostatic charge even when they are not plugged in.
  • A ground/polarity tester—This tester verifies proper grounding of power outlets.

A Note on Working Off-Site

When you work at a customer site, you must take the same precautions to avoid ESD damage. Take time to make the work area ESD-compliant. Take a workbench mat and a wrist strap with you. (For travel convenience, you may want to use a mat that folds up.) Be sure everything is properly grounded and never set parts on the floor.

ESD-Compliant Workstation Quiz

Read Knowledge Base document 50077, “ESD Prevention Rules”, and answer the following questions:

  1. When there is a risk of contacting high voltage, such as when you discharge a CRT or work with a powered-on CRT, do you wear a grounding wrist strap?
  2. When there is a risk of contacting high voltage, do you work on a grounded pad?
  3. What items do you need to set up an ESD-compliant workstation?
  4. For what do you use a ground/polarity tester?

Answer Key

1. No; 2. No; 3. A conductive workbench mat, a wrist strap with 1-megohm resistor and ground cord, a wire lead with alligator clips, and a ground/polarity tester; 4. To verify proper grounding of the power outlet.

Peachpit Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from Peachpit and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about Peachpit products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites; develop new products and services; conduct educational research; and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by Adobe Press. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive:

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020