How to Tab Your NEC for the Electrician Exam

A well-tabbed code book is the difference between a two-minute lookup and a twenty-second one, and over an exam that is the difference between finishing and not. Pre-printed tab sets are the right tool, but where they go and how you use them matters more than whether you own them.

What the rules allow

Check your state's candidate bulletin first. Nearly every state allows permanent tabs (printed or self-adhesive, attached so they cannot be removed without tearing) and highlighting or underlining. Many allow brief handwritten notes in the margins; some forbid handwriting entirely and inspect the book at check-in. None allow loose paper, sticky notes or anything inserted between pages. If the bulletin is silent, assume the strict version and keep the book clean apart from tabs and highlighter.

Which articles get a tab

Fifteen articles cover most of the exam. Tab each one at its first page:

• 100 Definitions
• 110 Requirements for Electrical Installations
• 210 Branch Circuits
• 215 Feeders
• 220 Branch-Circuit, Feeder and Service Load Calculations
• 230 Services
• 240 Overcurrent Protection
• 250 Grounding and Bonding
• 300 General Requirements for Wiring Methods
• 310 Conductors for General Wiring
• 314 Outlet, Device, Pull and Junction Boxes
• 404 Switches and 406 Receptacles
• 430 Motors
• 450 Transformers
• Chapter 9 Tables

For a master exam add 225 Outside Branch Circuits and Feeders, 408 Switchboards and Panelboards, 445 Generators, 517 Health Care Facilities, 700 Emergency Systems and the business-related sections your state tests.

Which tables get a tab

Tables are where the exam sends you for numbers, and a tab on the table beats a tab on the article:

• Table 310.16, conductor ampacity, and the temperature correction and adjustment tables that follow it (310.15(B) and (C))
• Table 250.66, grounding electrode conductor
• Table 250.122, equipment grounding conductor
• Table 250.102(C)(1), bonding jumper for service conductors
• Table 220.55, ranges, and 220.54, dryers
• Table 314.16(A) and (B), box fill
• Tables 430.52, 430.248, 430.250, motor protection and full-load currents
• Table 450.3(B), transformer overcurrent protection
• Chapter 9 Table 1 (percent fill), Table 4 (raceway areas), Table 5 (conductor areas), Table 8 (conductor properties)
• Annex C, conduit fill by conductor type

Placing them

Work from the front of the book to the back. Put each tab on the first page of the article or table, with the printed number facing out and the tab's edge flush with the page edge. Stagger the tabs down the side of the book in columns, so that article tabs run in one column and table tabs in another; a tab hiding behind another is worse than no tab.

Do this yourself, in one sitting, with the book open on the table and the table of contents beside you. It takes an hour. By the end of it you will know the order of the articles, which chapter holds what, and roughly how thick each article is. That hour is worth more than an evening of reading about the code's structure.

Highlighting

Highlight the lines you will need under pressure, not whole paragraphs: the 125 percent rule in 210.19 and 210.20, the next-size-up rule in 240.4(B), the small-conductor rule in 240.4(D), the receptacle spacing rule in 210.52, the working space dimensions in 110.26, the demand factor rows you use most in 220. Use one colour for rules and another for exceptions so your eye finds the exception you are about to miss.

Keep a clean book

The exam book and the study book should be the same book, but keep it in a condition that passes inspection. If your state forbids handwriting, do your margin notes in a separate copy of the study guide and leave the code clean. On exam morning, flip through once more for anything loose and take it out.

The tabs are not a shortcut around learning the code. They are the record of having learned where it is.