Exam guide

The NASCLA Electrical Exam Reference Books

Updated September 2026

The NASCLA Master/Unlimited electrical exam is open book - but only the approved references get through the door, and how well you know your way around them decides your score.

Here is the list, the one choice you get to make, and the tabbing rules.

The approved references

• National Electrical Code (NEC) or NEC Handbook - YOUR CHOICE of the 2020 or 2023 edition
• OSHA 29 CFR 1926 (construction) and 29 CFR 1910 (general industry) standards
• NFPA 70E, Standard for Electrical Safety in the Workplace (2024)
• Ugly's Electrical References (2023)
• NASCLA Contractors Guide to Business, Law and Project Management (14th edition)
• A Guide to the Project Management Body of Knowledge (PMBOK Guide, 7th edition)

The 2020-or-2023 choice

This exam is unusual: it accepts either the 2020 or the 2023 NEC, so you bring the edition you already own and work with. You do not need to buy the newer book to sit the exam.

Check the current PSI candidate bulletin before test day - reference lists get updated, and the bulletin is the final word on what gets through the door.

Tabbing rules

Permanent tabs are allowed and you should use them heavily - the difference between a 30-second look-up and a three-minute one is usually a tab. Loose papers and removable notes are not allowed, and books get inspected at check-in.

Tab the workhorses: Table 310.16, the adjustment factors, box fill in 314.16, conduit fill in Chapter 9 and Annex C, the motor tables in 430, transformer protection in 450.3, and the grounding tables 250.66 and 250.122.

Train with the books you will carry

Every practice question in our course cites the exact section or table the answer lives in - so every practice round doubles as navigation training in the actual books you will bring to the exam.

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