- What the 13 CAST Domains Actually Represent
- How the Domains Appear on Exam Day
- Walking Through All 13 Content Areas
- Domain Weighting and Where to Focus
- Scheduling Your Review Around the Domains
- Who Actually Tests These Skills on the Job
- Registration, Retakes, and Keeping the Credential Current
- Frequently Asked Questions
- CAST covers 13 base content areas defined in ETA International's official competency document.
- The exam is 75 questions in two hours with a 75% passing score, no reference sheets allowed.
- Stand-alone CAST has no prerequisite; Journeyman status later requires CETa plus two years of combined experience.
- One free retake is available within a year of your first attempt, though remote-proctoring fees apply separately.
What the 13 CAST Domains Actually Represent
The Certified Alarm Security Technician (CAST) credential from ETA International is built around a single competency document that lists 13 base sections - the same 13 covered in this guide. These aren't abstract "knowledge areas" pulled from a generic IT security framework; they map directly to what a low-voltage alarm and security technician does in the field, from running cable through a wall cavity to reading a schematic on a service call.
If you're just starting to research the credential, it helps to first understand what CAST certification actually verifies and how it differs from adjacent electronics credentials. This article assumes you already know the basics and want a domain-by-domain breakdown you can study against.
How the Domains Appear on Exam Day
Every one of the 13 domains is tested inside a single 75-question, two-hour written exam. There's no separate hands-on station and no domain-specific sub-score reported back to you - it's one combined pass/fail result measured against a 75% passing threshold. That format matters for how you prepare: you're not "passing" Domain 7 and "failing" Domain 11 separately, you're building enough cumulative accuracy across all 13 areas to clear 75% overall.
The exam is proctored through an ETA Certification Administrator using either Trapeza online testing or a paper form, and remote proctoring through ExamRoom.AI is also available if you can't get to a physical test site. No reference materials or formula sheets are permitted, though calculator use follows standard ETA rules - relevant given that Mathematics is one of the 13 domains.
Key Takeaway
Because there's no partial credit by domain, treat weak domains as equally dangerous to your overall score as strong ones are protective - don't let mastery of Cameras and Intercoms compensate for skipping Cabling and Connectors.
For a deeper look at exam mechanics like fees and scheduling logistics, see CAST Certification Cost 2026: Complete Pricing Breakdown and CAST Exam Dates 2026: Testing Windows, Deadlines & Scheduling.
Walking Through All 13 Content Areas
Below is a practical read on each domain as it's likely to show up in exam questions. Use this as a checklist alongside the official competency document rather than a replacement for it.
Domain 1: Technology and Configuration
Broad grounding in how security systems are structured and set up as integrated technology platforms rather than isolated devices.
- System architecture and how subsystems talk to each other
- Configuration steps during initial installation
Domain 2: Alarms
Core intrusion and life-safety alarm knowledge - the traditional heart of the trade.
- Sensor types, zones, and panel logic
- Arming/disarming sequences and false-alarm prevention
Domain 3: Cameras and Intercoms
Video surveillance and access-adjacent communication hardware, reflecting how modern alarm work overlaps with video and entry systems.
- Camera types, placement, and field-of-view basics
- Intercom wiring and integration with entry points
Domain 4: Components
Identification and function of the individual parts that make up a security system.
- Sensors, keypads, power supplies, and control boards
- Matching component specs to installation requirements
Domain 5: Cabling and Connectors
Physical layer knowledge: what wire goes where, and how it's terminated.
- Wire gauge, type, and run-length considerations
- Connector types and proper termination practices
Domain 6: Interfacing
How separate systems and devices are connected so they function as one - a recurring exam theme given how many domains touch integration.
- Input/output interfacing between panels and peripherals
- Compatibility checks across equipment brands
Domain 7: Locks
Physical security hardware knowledge that intersects with electronic access control.
- Lock types and their electronic counterparts
- Basic mechanical-to-electronic access concepts
Domain 8: Block Diagrams and Schematics
The ability to read and interpret system drawings - a skill tested through diagram-based questions rather than memorized facts.
- Symbol recognition
- Tracing signal flow through a schematic
Domain 9: Troubleshooting
Applied diagnostic reasoning across the other domains - this is where technicians prove they can find and fix, not just identify.
- Systematic fault isolation
- Common failure points in alarm and camera systems
Domain 10: Computers and Digital Concepts
Foundational digital literacy relevant to modern, networked security equipment.
- Basic computer architecture and terminology
- Digital vs. analog signal concepts
Domain 11: Hand Tools - Soldering
Hands-on tool knowledge tested in written form - expect questions on proper technique and tool selection rather than a live soldering station.
- Correct soldering technique and safety
- Appropriate hand tools for common installation tasks
Domain 12: Data Communications and Software
How security systems transmit data and interact with software, including monitoring and reporting functions.
- Communication protocols used in alarm reporting
- Software interfaces for programming and monitoring
Domain 13: Mathematics
Applied math for electronics work - expect calculation-based questions rather than abstract theory.
- Ohm's law and basic circuit calculations
- Unit conversions relevant to cable runs and power
Domain Weighting and Where to Focus
ETA International does not publish a percentage breakdown of how many of the 75 questions come from each of the 13 domains, so resist the urge to chase invented weighting numbers you might see elsewhere. The safer strategy is to treat every domain as fair game and prioritize based on your own weak spots rather than a guessed scoring formula.
| Domain Cluster | Why It Matters |
|---|---|
| Alarms, Components, Cabling and Connectors | Core hardware knowledge underlying most field work |
| Block Diagrams, Troubleshooting, Interfacing | Applied reasoning skills tested through scenario-style questions |
| Mathematics, Computers and Digital Concepts | Calculation and digital literacy questions that trip up experience-only candidates |
| Cameras and Intercoms, Locks, Data Communications and Software | Newer or adjacent-system knowledge that broadens the exam beyond classic alarm wiring |
For a candid assessment of how tough this spread actually is in practice, see How Hard Is the CAST Exam? Complete Difficulty Guide 2026 and CAST Pass Rate 2026: What the Data Shows.
Scheduling Your Review Around the Domains
A domain-by-domain schedule works better than open-ended review because it forces contact with all 13 areas instead of over-indexing on whatever feels comfortable. Here's a simple four-week structure built around the domain groupings above.
Hardware Foundations
- Alarms, Components, Cabling and Connectors, Locks
- Drill component identification and wiring termination scenarios
Diagrams and Diagnostics
- Block Diagrams and Schematics, Troubleshooting, Interfacing
- Practice tracing signal flow and isolating faults on sample diagrams
Digital and Applied Math
- Computers and Digital Concepts, Data Communications and Software, Mathematics
- Rehearse Ohm's law and conversion problems without a reference sheet, since none is allowed
Integration and Review
- Cameras and Intercoms, Hand Tools - Soldering, Technology and Configuration
- Full-length timed practice runs mimicking the 75-question, two-hour format
For a more detailed walkthrough of resources and pacing, pair this timeline with the CAST Study Guide 2026: How to Pass on Your First Attempt, and use timed practice sets on our practice test platform to simulate exam-day pressure across all 13 domains at once.
Who Actually Tests These Skills on the Job
The domain list isn't academic - it reflects the actual day-to-day of alarm and security installers, service technicians, and low-voltage integrators. Employers hiring for these roles look for exactly the mix covered here: someone who can pull cable correctly (Domain 5), read a panel schematic (Domain 8), diagnose a dead zone (Domain 9), and safely solder a connection in the field (Domain 11).
If you're weighing whether the credential is worth pursuing relative to your career goals, Is the CAST Certification Worth It? Complete ROI Analysis 2026 and CAST Salary Guide 2026: Complete Earnings Analysis go into that in more depth. For a sense of what postings actually ask for, CAST Jobs breaks down common employer expectations tied to these same domains.
Registration, Retakes, and Keeping the Credential Current
A few mechanical details matter once you're ready to schedule against these 13 domains. The exam fee is $80, and if you choose remote proctoring through ExamRoom.AI, the two-hour session adds $16 on top of that. Stand-alone CAST has no CETa prerequisite - it's open to candidates without prior ETA credentials - while Journeyman status is a separate track requiring CETa plus at least two years of combined training and experience.
If you don't clear the 75% passing score on your first attempt, one free retake is available within one year of your original session, though any remote-proctoring charges for that retake session are billed separately. Once certified, the credential runs on a four-year term, maintained through 10 continuing-education hours annually (40 total over four years) or documented employer/supervisor verification under ETA policy, at a maintenance cost of $25 per year or $100 for the full four years.
For the full eligibility picture and exact passing-score math, see CAST Requirements 2026: Eligibility, Prerequisites & How to Qualify and CAST Passing Score 2026: Exactly What You Need to Pass. A condensed one-page reference covering all 13 domains is also available in the CAST Cheat Sheet 2026: One-Page Review of Must-Know Facts, and you can run domain-tagged questions any time on our practice exam site.
Frequently Asked Questions
ETA International doesn't publish an official percentage breakdown by domain, so there's no confirmed weighting to study around. The safest approach is even preparation across all 13 areas rather than assuming any one domain dominates the 75 questions.
No. The base CAST exam is entirely written and proctored, with no hands-on examination component, so even physical-skill domains like soldering and cabling are tested through written questions.
Stand-alone CAST does not require CETa or any prerequisite credential. CETa plus two years of combined training and experience is only required later if you pursue Journeyman status.
Calculator use is allowed but follows ETA's specific rules for the exam. No reference materials or formula sheets are permitted for any domain, including Mathematics.
You get one free retake within one year of your first exam session. Remote-proctoring fees for that retake are charged separately from the free retake itself.
Mastering all 13 CAST domains comes down to treating the credential as what it is: a practical field-skills exam covering everything from cable termination to applied math, tested in one combined 75-question sitting. Study each domain deliberately, know the registration mechanics cold, and you'll walk into test day with no surprises.