- CHT eligibility requires documented clinical internship hours in hyperbaric technology - not just classroom training.
- The exam covers six specific domains, including Gas Systems, Chamber Operations, and a dedicated TCOM Monitoring Module.
- Domain 1 (Minimum General Requirements) sets the baseline - meet it first before focusing on clinical content.
- TCOM Monitoring is a separate module; understand whether you are testing for it as part of your application.
Who the CHT Credential Is For
The Certified Hyperbaric Technologist (CHT) credential is the professional standard for individuals who operate hyperbaric chambers, manage gas delivery systems, and support clinical hyperbaric oxygen therapy (HBOT) under physician supervision. If you work in a hospital-based wound care center, a freestanding hyperbaric clinic, or a military or research hyperbaric facility, the CHT is the credential your employer looks for when evaluating technical competency.
Unlike broad allied health certifications, the CHT is deliberately narrow in scope. It validates that a candidate can perform the hands-on, safety-critical tasks specific to hyperbaric environments - from managing 100% oxygen delivery at pressure to monitoring patients inside a monoplace or multiplace chamber. Employers who hire CHTs include hospital outpatient wound care programs, hyperbaric surgery centers, dive medicine clinics, and research institutions with pressurized testing environments.
Eligibility Requirements Broken Down
Before you can sit for the CHT exam, you must satisfy the criteria outlined in Domain 1: Minimum General Requirements. This domain is not just an introductory content area on the test - it literally defines who is permitted to apply. Understanding exactly what qualifies and what does not will save you from a rejected application or a delayed test date.
What "Minimum General Requirements" Actually Covers
Domain 1 establishes the floor for candidacy. This includes educational background, professional standing, and the verified clinical experience that must be on file before your application is reviewed. The word "minimum" is important: meeting these thresholds means you are eligible to test, not that you are guaranteed to pass. Candidates who rush to meet minimums without developing genuine clinical knowledge often struggle with the deeper applied content in Domains 2 through 6.
Key eligibility gatekeepers include:
- Current or active status in a recognized healthcare or hyperbaric-adjacent profession - the CHT is not an entry-level credential for individuals with no clinical background.
- Documented clinical internship hours in hyperbaric technology, completed under the supervision of a qualified hyperbaric professional. The specifics of logging and finding these hours are covered in detail in the article CHT Clinical Internship Hours: How to Find and Log Them.
- Completion of a formal hyperbaric training course recognized by the certifying body - self-study alone does not substitute.
A Note on the TCOM Module
Domain 6 - Transcutaneous Oxygen (TCOM) Monitoring Module - exists as a separately designated area of the exam. If your facility uses TCOM as part of its wound assessment or treatment authorization workflow, demonstrating competency here strengthens your clinical profile significantly. Confirm at the time of application whether you are registering for the full exam including this module, as it affects both your study plan and your exam scope.
| Eligibility Element | What to Confirm Before Applying |
|---|---|
| Healthcare/Professional Background | Active licensure or recognized role in clinical or hyperbaric setting |
| Formal Hyperbaric Training Course | Course recognized by the certifying body; obtain certificate of completion |
| Clinical Internship Hours | Hours documented and supervisor-verified in approved hyperbaric setting |
| TCOM Module Election | Decide at registration whether to include Domain 6 in your exam |
| Application Documentation | Verification letters, training certificates, and employer confirmation ready |
The Six Exam Domains You Must Master
The CHT exam is organized around six domains, and your preparation should mirror that structure. Each domain represents a distinct body of knowledge - and distinct categories of questions you will encounter on test day. Here is what each domain actually demands from a candidate.
Domain 1: Minimum General Requirements
Sets eligibility criteria and tests foundational knowledge of hyperbaric standards, safety regulations, and professional scope of practice in hyperbaric technology.
- NFPA 99 and related fire and safety codes in hyperbaric environments
- Scope of practice distinctions between CHT, CHS, and CHN credentials
- Regulatory and accreditation frameworks governing hyperbaric facilities
Domain 2: Gas Systems
Tests deep knowledge of oxygen, air, and mixed-gas delivery systems. This is a high-stakes domain because errors in gas management can cause fires, equipment failure, or patient harm.
- Bulk oxygen storage systems, manifolds, and pressure regulation
- Medical-grade gas purity standards and cylinder identification
- Oxygen fire risk mitigation and ignition source control
- Compressed air systems for multiplace chamber operations
Domain 3: Chamber Operations and Environment
Covers the mechanical and operational knowledge required to safely pressurize, maintain pressure, and decompress a hyperbaric chamber.
- Monoplace vs. multiplace chamber differences in operation protocols
- Compression and decompression rates and their clinical implications
- Fire suppression systems, chamber maintenance, and documentation
- Environmental controls including temperature, humidity, and CO2 management
Domain 4: Clinical Skills and Generalized Clinical Knowledge
The broadest clinical domain, requiring candidates to demonstrate understanding of patient assessment, physiological effects of pressure, and emergency response inside the hyperbaric environment.
- Indications and contraindications for hyperbaric oxygen therapy
- Oxygen toxicity recognition and management
- Middle ear and sinus barotrauma assessment
- Emergency procedures including in-chamber cardiac events
- Patient screening and pre-treatment clinical documentation
Domain 5: Clinical Internship in Hyperbaric Technology
Validates competencies acquired during supervised clinical practice. Questions in this domain test whether candidates can apply procedural and safety knowledge in real-world hyperbaric scenarios.
- Proper patient preparation and chamber entry procedures
- In-chamber monitoring and communication protocols
- Logging and documentation requirements during treatments
Domain 6: Transcutaneous Oxygen (TCOM) Monitoring Module
A specialized module covering the use of TCOM equipment to measure tissue oxygenation before, during, and after hyperbaric treatment for wound care patients.
- TCOM electrode placement and calibration procedures
- Interpreting periwound TcPO2 readings in clinical context
- Using TCOM data to support treatment planning decisions
- Equipment troubleshooting and documentation standards
The Clinical Internship Requirement
Of all the eligibility requirements, the clinical internship hours are the one that most frequently delays candidates. Unlike a written course you can complete on your own schedule, internship hours depend on facility access, supervisor availability, and proper documentation practices - all of which take time to coordinate.
The internship connects directly to Domain 5 of the exam. Questions in that domain are not abstract - they test whether you have actually performed the procedures, operated the equipment, and navigated real patient scenarios. Candidates who approach Domain 5 as purely a reading exercise tend to struggle on questions that require procedural judgment.
For a complete guide to finding a qualifying facility, understanding what counts toward your hours, and building a log that survives application review, see CHT Clinical Internship Hours: How to Find and Log Them. The documentation habits you build during your internship will directly reflect in your test performance - and in how you perform on the job afterward.
Key Takeaway
Start pursuing your clinical internship placement as early as possible. Many candidates underestimate the lead time required to connect with a qualifying facility, obtain supervisor sign-off, and complete enough hours to meet eligibility - all before they can even submit an application.
Registration, Fees, and Application Mechanics
Once you have confirmed you meet Domain 1 eligibility, the application process involves assembling documentation and submitting it to the certifying body. The CHT is administered by the National Board of Diving and Hyperbaric Medical Technology (NBDHMT). Understanding the administrative mechanics prevents delays and avoids the frustration of incomplete submissions.
What to Prepare Before You Open the Application
- Training course certificate from a NBDHMT-recognized hyperbaric training program
- Clinical internship log with supervisor verification signatures
- Professional license or credential documentation demonstrating active standing in your healthcare role
- Employer or facility letter confirming your hyperbaric work environment if applicable
Applications that arrive incomplete are not simply returned for correction - they consume processing time and delay your eligibility window. Treat the application checklist as seriously as you treat your study plan.
Exam Format Expectations
The CHT exam is a computer-based multiple-choice examination. Questions are written to test applied knowledge, not rote memorization - meaning you will frequently see scenario-based items that describe a chamber situation or patient presentation and ask you to identify the correct technologist response. This format rewards candidates who have genuinely internalized the clinical and operational content across all six domains.
After you submit your application and it is approved, you will receive authorization to schedule your exam. Use that window strategically. If you are not yet confident across Domains 2, 3, and 4 - the heaviest technical content areas - take the additional preparation time rather than testing prematurely.
The best way to calibrate your readiness before exam day is to practice with questions written in the CHT format. Our CHT practice test platform mirrors the applied, scenario-based style of real exam items across all six domains.
Structuring Your Study Around the Domains
Most CHT candidates have a clinical background that gives them natural strength in some domains and gaps in others. A respiratory therapist may be comfortable with gas systems but less experienced with TCOM. A wound care nurse may understand clinical indications well but need significant work on chamber operations mechanics. Build your schedule around your actual gaps - not a generic template.
The following is a domain-focused six-week framework. Adjust based on your current knowledge and the number of hours per week you can commit.
Domain 1 + Eligibility Self-Audit
- Review NFPA 99 hyperbaric facility requirements
- Confirm all application documents are gathered and complete
- Map your professional background to Domain 1 scope of practice content
Domain 2: Gas Systems Deep Dive
- Master oxygen storage, manifold design, and pressure regulation sequences
- Review fire risk scenarios and oxygen-enriched atmosphere protocols
- Practice scenario questions on gas delivery failures
Domain 3: Chamber Operations
- Compare monoplace and multiplace compression/decompression protocols
- Study environmental control systems (CO2 scrubbers, temperature regulation)
- Review chamber maintenance documentation requirements
Domain 4: Clinical Knowledge
- Review all HBOT indications and absolute/relative contraindications
- Master oxygen toxicity recognition and emergency response steps
- Study barotrauma assessment for ear, sinus, and pulmonary involvement
Domain 5: Clinical Internship Application + Domain 6: TCOM
- Review your internship logs and reinforce procedural knowledge gaps
- Study TCOM electrode placement, calibration, and result interpretation
- Practice TCOM scenario questions using clinical wound care contexts
Full-Length Practice + Weak Domain Remediation
- Complete at least two timed full-length practice exams
- Identify lowest-scoring domains and do targeted review
- Use CHT Exam Prep practice tests to simulate real exam conditions
The Pomodoro technique (25-minute focused blocks with 5-minute breaks) works particularly well for the memorization-heavy content in Domain 2 and Domain 6, where terminology and procedural sequences must be retained precisely. Pair it with spaced repetition flashcards for gas system specifications and TCOM interpretation thresholds.
Frequently Asked Questions
Not necessarily. The CHT credential is open to individuals with various clinical or hyperbaric-adjacent backgrounds, provided they meet the Domain 1 minimum requirements. Review the NBDHMT's eligibility criteria carefully to confirm your specific professional background qualifies before applying.
No. Verified clinical internship hours are a prerequisite for application approval, not something you complete after testing. Your hours must be documented and supervisor-verified before your application can be processed. See our detailed guide on CHT Clinical Internship Hours: How to Find and Log Them for practical strategies.
Domain 6 is a designated module within the CHT exam structure. Whether it is required or elected depends on your application and the scope of practice at your facility. Confirm this detail with the NBDHMT at the time of registration so you study the appropriate content and register for the correct exam version.
The CHT uses multiple-choice questions in a computer-based format. Many items are scenario-based - they describe a clinical or operational situation and ask you to identify the correct technologist response. Pure memorization is insufficient; you must be able to apply knowledge to realistic hyperbaric scenarios across all six domains.
Most candidates benefit from a minimum of six to eight weeks of structured domain-by-domain review after completing their training and internship requirements. If you have significant gaps in gas systems or chamber operations knowledge, build in additional time for those domains before scheduling your exam date.
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