- Exam Overview: Format, Fees, and Scoring
- The 8 MD-ME Content Areas at a Glance
- Domain 1: Electrical Theory
- Domain 2: Wiring and Protection
- Domain 3: Wiring Methods and Materials
- Domain 4: Equipment for General Use
- Domain 5: Special Occupancies
- Domain 6: Special Equipment
- Domain 7: Special Communications
- Domain 8: Calculations (The Largest Domain)
- Mapping a Study Schedule to the Domains
- Frequently Asked Questions
- The MD-ME exam has 90 questions worth 100 points, with a 4-hour limit and 70% passing score.
- Calculations is the largest domain, so it deserves the most study hours of all 8 areas.
- Ten Electrical Theory questions are worth two points each - more weight per question than most other items.
- Only the 2020 NEC with permanent tabs, highlighting, and underlining is allowed as a reference in the testing room.
Exam Overview: Format, Fees, and Scoring
Before breaking down the eight content areas, it helps to understand the exam mechanics set by the Maryland State Board of Electricians and administered through PSI. The Master Electrician exam is computer-delivered and open-book, with 90 questions worth a combined 100 points. Candidates get a 4-hour limit to finish, and a 70% score is required to pass. The $65 examination fee covers your seat at a PSI testing center, and if you don't pass, the first retest requires a 30-day wait, while later retests require 60 days between attempts.
One quirk worth internalizing early: ten Electrical Theory questions are worth two points each, rather than the standard one point applied elsewhere on the exam. That means Domain 1 carries disproportionate weight relative to its question count, and skipping it in your prep can cost you more than you'd expect. PSI also reserves the right to add 5-10 unscored experimental questions to any given form of the exam - these look identical to scored items, so the only reasonable strategy is to treat every question as if it counts.
For a full walkthrough of eligibility rules, including the seven years of qualifying electrical-services experience and the up to three years of credit available for approved formal study, see MD-ME Requirements 2026: Eligibility, Prerequisites & How to Qualify. If you want a broader look at overall exam difficulty before diving into domains, check How Hard Is the MD-ME Exam? Complete Difficulty Guide 2026.
The 8 MD-ME Content Areas at a Glance
The Maryland Master Electrician exam blueprint organizes all 90 questions into eight domains. Each domain maps to a distinct body of NEC knowledge and field experience:
- Domain 1: Electrical Theory
- Domain 2: Wiring and Protection
- Domain 3: Wiring Methods and Materials
- Domain 4: Equipment for General Use
- Domain 5: Special Occupancies
- Domain 6: Special Equipment
- Domain 7: Special Communications
- Domain 8: Calculations
Calculations is officially the largest domain on the exam, which should shape how you allocate study time across the other seven. We'll go domain by domain below, then show you how to sequence your review around this weighting in the study plan section.
Domain 1: Electrical Theory
Electrical Theory
This domain tests your grasp of the fundamental physics and math that underlie every other domain on the exam. Because ten of these questions are worth two points each, Domain 1 has outsized influence on your final score relative to its question count.
- Ohm's Law and Watt's Law relationships across series and parallel circuits
- Power factor, true power vs. apparent power, and basic AC/DC distinctions
- Voltage drop concepts and how they connect to later calculation-heavy questions
- Transformer theory basics, including turns ratios and single-phase vs. three-phase relationships
Candidates who treat theory as an afterthought often struggle disproportionately here because the math skills reinforced in this domain resurface throughout Domain 8. Building fluency early pays dividends across the whole exam.
Domain 2: Wiring and Protection
Wiring and Protection
This domain centers on how conductors are sized, protected, and terminated in accordance with the NEC. Expect questions that require you to cross-reference multiple code tables in sequence.
- Overcurrent protection device sizing and coordination
- Grounding and bonding requirements, including equipment grounding conductors
- Conductor ampacity, adjustment, and correction factors
- Branch circuit and feeder requirements
Because this material draws heavily on NEC tables, practicing with your actual tabbed code book - not just a digital PDF - builds the navigation speed you'll need on exam day.
Domain 3: Wiring Methods and Materials
Wiring Methods and Materials
This area covers the physical installation rules for cables, raceways, boxes, and enclosures - the everyday fieldwork knowledge every master electrician applicant should have internalized long before test day.
- Cable and raceway fill calculations and support spacing
- Box sizing and conductor fill requirements
- Approved wiring methods for different environments (wet, damp, corrosive)
- Splicing, termination, and enclosure requirements
Domain 4: Equipment for General Use
Equipment for General Use
This domain shifts focus from wiring infrastructure to the equipment connected to it - switches, receptacles, motors, and general-use appliances.
- Switch and receptacle requirements, including GFCI/AFCI placement rules
- Motor circuit sizing, overload protection, and disconnect requirements
- Lighting fixture installation and clearance rules
- Appliance branch circuit requirements
Many candidates find that hands-on field experience translates well here, but the NEC's specific numeric thresholds (clearances, ampacity multipliers) still need direct memorization or quick lookup skills.
Domain 5: Special Occupancies
Special Occupancies
Special occupancies address locations with unique hazards - hazardous locations, health care facilities, places of assembly, and similar environments where standard wiring rules don't fully apply.
- Hazardous (classified) location classifications and equipment requirements
- Health care facility branch circuit and grounding requirements
- Assembly occupancies and theaters
- Agricultural buildings and similarly specialized spaces
Domain 6: Special Equipment
Special Equipment
This domain covers equipment types that fall outside general wiring and general-use equipment - items with their own dedicated NEC articles.
- Electric signs and outline lighting
- Elevators, dumbwaiters, and escalators
- Electric vehicle charging equipment
- Swimming pools, fountains, and similar installations
Because these topics each live in narrow, self-contained NEC articles, they respond well to focused, article-by-article review sessions rather than broad conceptual study.
Domain 7: Special Communications
Special Communications
This is typically one of the smaller domains but still requires accurate recall of separation and installation rules for low-voltage and communications systems.
- Communications circuit requirements and separation from power conductors
- Fire alarm system wiring rules
- Optical fiber cable installation
- Network and broadband communications wiring
Domain 8: Calculations (The Largest Domain)
Calculations
Calculations is confirmed as the largest domain on the Maryland Master Electrician exam, making it the single highest-priority content area for study time. Every calculation topic draws on the Electrical Theory foundation from Domain 1, so weak fundamentals here compound quickly.
- Service and feeder load calculations (standard and optional methods)
- Demand factors for dwelling units and commercial occupancies
- Voltage drop calculations across conductor runs
- Motor and transformer sizing calculations
- Conduit and box fill calculations
Key Takeaway
Since Calculations is the largest domain, practice full load-calculation problems from start to finish under timed conditions - not just isolated formulas - so you can move through multi-step problems efficiently within the 4-hour limit.
Because calculations problems are open-book but time-intensive, being fast with your NEC table lookups matters as much as knowing the formulas. This is one of the clearest places where the open-book format helps candidates who've practiced flipping to load calculation tables quickly and hurts those who haven't.
Mapping a Study Schedule to the Domains
Rather than studying all eight domains equally, allocate time proportional to weight and difficulty. Since Calculations is the largest domain and draws directly on Electrical Theory, those two areas should anchor your early study weeks, with the remaining six domains layered in as you build code-navigation speed.
Foundations
- Review Electrical Theory formulas and drill Ohm's/Watt's Law problems
- Build NEC tab system for quick article lookup
Wiring Core
- Work through Wiring and Protection and Wiring Methods and Materials
- Practice ampacity, fill, and grounding table lookups
Equipment and Specialty Topics
- Cover Equipment for General Use, Special Occupancies, Special Equipment, and Special Communications
- Use article-by-article flashcards for narrow topics
Calculations Intensive
- Run full timed load-calculation problems daily
- Take practice exams that mirror the 90-question, 4-hour format
For a more detailed week-by-week methodology, including how to structure review sessions and track weak areas, see MD-ME Study Guide 2026: How to Pass on Your First Attempt. And if you want a condensed reference for last-minute review, the MD-ME Cheat Sheet 2026: One-Page Review of Must-Know Facts summarizes must-know facts across all eight domains.
You can build genuine familiarity with the domain structure and question style by running full-length simulated exams on our practice test platform before your official test date. Repeated exposure to the 90-question format under a 4-hour clock is one of the most reliable ways to confirm you're ready.
| Exam Element | Detail |
|---|---|
| Total Questions | 90 |
| Total Points | 100 |
| Time Limit | 4 hours |
| Passing Score | 70% |
| Electrical Theory Questions | 10 questions, 2 points each |
| Unscored Experimental Questions | 5-10 (added by PSI) |
| Allowed Reference | 2020 NEC (tabbed, highlighted, underlined only) |
| Largest Domain | Calculations |
Once you've passed, remember that the domains you studied don't disappear from your professional life. Master licenses are valid for two years, and masters authorized to provide electrical services must complete 10 continuing-education hours for renewal, in addition to maintaining at least $300,000 in general-liability insurance and $100,000 in property-damage insurance. For a full cost breakdown covering the $65 exam fee, the $25 original license fee, and the $31.50 renewal fee, see MD-ME Certification Cost 2026: Complete Pricing Breakdown.
If you're still deciding whether to pursue this credential or want context on how it fits into a broader electrical career, Is the MD-ME Certification Worth It? Complete ROI Analysis 2026 and MD-ME Salary Guide 2026: Complete Earnings Analysis cover those angles in depth. Employers hiring for master-level roles - from electrical contracting firms to facilities management teams across Maryland - expect fluency across all eight of these domains, not just theoretical knowledge of the code.
Frequently Asked Questions
Calculations is confirmed as the largest domain on the Maryland Master Electrician exam, so it should receive the largest share of your study time relative to the other seven domains.
The ten Electrical Theory questions are each worth two points, compared to the standard scoring on most other items across the 90-question, 100-point exam, giving Domain 1 extra weight per question.
No. The exam is open-book with the 2020 NEC permitted, including permanent tabs, highlighting, and underlining, but handwritten notes, loose papers, and study guides are prohibited.
Not necessarily. PSI may add 5-10 unscored experimental questions to the exam, and since these are indistinguishable from scored questions, candidates should answer every item carefully.
Domain performance doesn't change the wait time itself, but reviewing your weakest domains matters: the first retest request requires a 30-day wait, and later retest requests require 60 days, so focused domain review during that window is essential.