Open-Book NEC Rules and Tabs for the Texas Electrician Exam

Every Texas electrician exam at PSI is open book. That helps only if your book is allowed through check-in and set up so you can find things fast. This guide covers exactly what PSI allows, what it forbids, and how to prepare a book within those rules.

Key facts

• You bring your own soft-bound National Electrical Code. PSI does not supply one.
• Questions are based on the edition TDLR adopted: the 2026 NEC since September 1, 2026.
• Highlighting, underlining and notes are allowed if you add them before the exam.
• Only permanent index tabs made or supplied by the NEC publisher are allowed.
• Not allowed: homemade or DIY tabs, spiral or ring binding, loose-leaf copies, the NEC Handbook, any added paper, and marking the book during the exam.
• PSI provides an electronic notepad for your working.

What PSI allows and forbids

This is a paraphrase of the reference material page in the PSI Candidate Information Bulletin, updated 9/15/2026.

Allowed	Not allowed
Your own soft-bound NEC	Loose-leaf, spiral-bound or ring-bound copies
Highlighting made before the exam	Highlighting, underlining or writing during the exam
Underlining made before the exam	Homemade, DIY or non-publisher tabs
Notes written in the book before the exam	Any added paper: loose, taped, adhered or stapled
Permanent index tabs made or supplied by the NEC publisher	The NEC Handbook

PSI says any soft-bound edition of the NEC may be used, but the questions follow the edition TDLR has adopted. TDLR adopted the 2026 NEC effective September 1, 2026, and the bulletin says the exams are referenced to it from that date. If you bring a 2023 book, it is allowed, but many answers will be in different places. The biggest move: TDLR’s November 2026 newsletter notes that dwelling load calculations are now in Article 120.

What happens if your book breaks the rules

PSI gives three options to a candidate who arrives with a non-compliant book:

1. Take the exam without the book.
2. Remove the homemade tabs yourself and test with the book.
3. Forfeit the exam fee and come back another day with a compliant book, at your own cost.

Violations during the exam, such as marking the book, are reported to TDLR. PSI says they can lead to surrendering your materials, including the code book, an invalidated score, and civil or criminal penalties.

Option 2 sounds easy, but pulling dozens of tabs at check-in is stressful and eats into your arrival time. Get it right at home.

How to set up your book, step by step

1. Get the right book

Buy a soft-bound 2026 NEC. A book with a cracked spine that has been rebound with a spiral or put in a binder is no longer allowed.

2. Add publisher tabs only

If you want tabs, use the permanent index tab set made or supplied by the NEC publisher. Do not add your own flags, color tabs or cut paper. A plain book with good highlighting beats a book that gets stopped at check-in.

3. Highlight what you use for calculations

Highlighting is where your book becomes a tool. Spend it on the tables and rules you will use under time pressure. These are the ones our calculation drills use most. Section numbers can shift between editions, so find each one through your own 2026 book’s index before you highlight it.

Topic	What to highlight	Drill
Dwelling and commercial loads	Article 120: unit loads per square foot, small-appliance and laundry loads, the range, dryer and appliance demand factors, the neutral rules, the optional dwelling and multifamily methods	Dwelling standard load, range demand
Conductor ampacity	Table 310.16, the ambient temperature correction table and the adjustment table for more than three current-carrying conductors	Conductor sizing, ampacity correction
Continuous loads	The 125% rules for branch circuits and feeders, and the matching overcurrent device rules	Continuous loads
Breakers and fuses	Standard ampere ratings in Article 240 and the small conductor rule	OCPD sizing
Grounding	The grounding electrode conductor table (250.66) and the equipment grounding conductor table (250.122)	GEC sizing, EGC sizing
Boxes	The box volume tables and the counting rules in 314.16, and pull box sizing in 314.28	Box fill, pull box sizing
Conduit fill	Chapter 9 Table 1 (percent fill), Table 4 (conduit areas), Table 5 (conductor areas), and the Annex C tables	Conduit fill
Voltage drop	Chapter 9 Table 8 (conductor properties)	Voltage drop
Motors	The full-load current tables at the end of Article 430, the 125% conductor rule, the overload rules and the maximum OCPD table	Motor FLC, motor OCPD
Transformers	The overcurrent protection tables in 450.5 (450.3 in the 2023 NEC)	Transformer protection

Tips that keep highlighting useful:

• Use one color for “tables I calculate from” and a second for definitions and conditions in the notes. Two colors are easy to read; five are not.
• Highlight table titles and column headers, not only values. Under pressure, the mistake is reading the wrong column.
• Underline the condition words in a rule (“not more than”, “continuous”, “copper”). Those words decide answers.

4. Write short notes before the exam

PSI allows notes made before the exam. Keep them short and next to the rule they belong to. Examples that save time:

• Beside the motor tables: “Use table FLC for conductors and OCPD; nameplate for overloads.”
• Beside the voltage drop table: “1-phase: 2 × K × I × L ÷ CM. 3-phase: 1.732 × K × I × L ÷ CM.”
• Inside the front cover: a short list of the page numbers you use most.

Write in the book itself. A sheet slipped inside or taped to the cover is added paper and is not allowed.

5. Practice with the book you will bring

Do every drill on this site with your exam book open. Your code lookup drills and timed practice tests should use the same book, tabs and highlights you will carry into PSI. By exam day your hands should know where Table 310.16 is.

What not to do

• Do not bring printouts, a formula sheet or loose pages inside the book.
• Do not bring the NEC Handbook, even as a second book.
• Do not plan to mark up the book during the exam. Use the electronic notepad PSI provides.
• Do not use homemade tabs and hope for the best. PSI states the options, and none of them helps you.

Related rules

If you test in Spanish, PSI also allows a bound word-to-word translation dictionary, with its own rules. See taking the exam in Spanish. For the calculator rules, see calculator rules, and for check-in, see exam day at PSI. The 2026 NEC changes page lists what moved since 2023, and the formula sheet is the reference to study from, not to bring.

TexasElectricianExam is an independent study site, not affiliated with TDLR, PSI or NFPA. Confirm the current rules in the PSI bulletin before your exam.