- ACHRN is an advancement from CHRN through documentation, not a separate exam to sit for.
- Applicants need three years of CHRN status plus at least 480 hyperbaric hours in the prior 12 months.
- You must submit 60 continuing education hours from the last four years, including at least 30 Category A HBOT hours.
- Document at least two of four contribution categories with manager or medical-director verification.
What "ACHRN Training" Actually Means
Searches for "ACHRN training" often assume there's a dedicated exam-prep course sitting alongside the CHRN track. There isn't. The Advanced Certified Hyperbaric Registered Nurse credential, administered by the Baromedical Nurses Association Certification Board (BNACB) through the National Board of Diving and Hyperbaric Medical Technology (NBDHMT), is an advancement pathway built on documented qualifications and professional contributions - not a second multiple-choice test. If you're already picturing flashcards and a timed exam window for "the ACHRN exam," you're thinking of the wrong stage of the process.
Real ACHRN training happens in two phases: first, passing the CHRN examination and working the required hyperbaric hours; second, assembling a documentation file that proves your experience, continuing education, and professional contributions meet the advancement form's standards. This article walks through both phases so you know exactly what to prepare, in what order, and what evidence to collect along the way.
The CHRN Prerequisite You Must Complete First
Before any ACHRN training conversation is relevant, you need current CHRN certification and a valid RN license. The CHRN exam itself is the only actual examination in this pathway: 120 multiple-choice and true/false questions, completed in two hours, with a 70% passing score required. Everything labeled as "exam prep" on this site refers to that CHRN prerequisite - we deliberately label it CHRN rather than presenting a nonexistent ACHRN exam, and you should hold any other resource to the same standard.
If you haven't sat the CHRN exam yet, that's where your preparation energy belongs first. Our ACHRN Study Guide 2026: How to Pass on Your First Attempt walks through structuring that CHRN-level preparation, and the ACHRN Exam Domains 2026: Complete Guide to All 0 Content Areas article breaks down the content areas the underlying exam draws from. If you're unsure how the exam actually feels under time pressure, How Hard Is the ACHRN Exam? Complete Difficulty Guide 2026 and ACHRN Passing Score 2026: Exactly What You Need to Pass both address that directly.
Once you're a practicing CHRN, the clock on ACHRN eligibility starts. According to the June 2024 resource manual, an advanced application becomes possible after three years of CHRN certification. Nothing in that window is wasted time - it's when you accumulate the hours, continuing education, and contribution evidence the advancement form requires.
Key Takeaway
Don't search for ACHRN-specific test questions. Direct all exam-preparation effort toward the CHRN exam, then shift to documentation-building once you're certified.
Building Your Advancement Documentation File
The August 2025 advancement/recertification form spells out exactly what your file needs to contain. Treat this as a checklist you build gradually over your three years of CHRN practice, not something you assemble in a scramble the month before applying.
Core Eligibility Documentation
These are the baseline items every applicant must have on file before the advancement package can be considered complete.
- Current CHRN certification status, unbroken
- A valid, unrestricted RN license
- At least three years of documented hyperbaric nursing experience
- Manager or medical-director verification of at least 480 hyperbaric hours in the preceding 12 months
That 480-hour figure is worth flagging separately because it's tied to a rolling 12-month window, not your career total. If your hyperbaric unit assignment fluctuates, track your hours quarterly so you're never caught short when it's time to submit the form. Ask your manager or medical director early whether they're comfortable providing the required verification signature - securing that commitment months in advance avoids a bottleneck at submission time.
For a full breakdown of every eligibility line item, see ACHRN Requirements 2026: Eligibility, Prerequisites & How to Qualify, which pairs well with this training guide.
Continuing Education Planning for Advancement
Alongside hours and tenure, the advancement form requires 60 continuing education hours accumulated over the preceding four years, with at least 30 of those hours classified as Category A hours specifically in hyperbaric oxygen therapy. This is where "ACHRN training" in the colloquial sense actually lives - not exam cramming, but deliberate CE selection.
Category A Hyperbaric Oxygen Therapy Hours
These need to be the backbone of your four-year CE log. Prioritize courses and conferences that explicitly designate Category A credit in HBOT topics over generic nursing CE that won't count toward the 30-hour minimum.
- Confirm Category A designation before registering for any course
- Keep certificates and course descriptions, not just credit totals
- Spread hours across the four-year window rather than back-loading them
A simple tracking spreadsheet - course name, date, hours, category, certificate location - saves enormous stress when you're preparing your submission packet. Since the four-year lookback is fixed, hours earned too early can expire before you apply; plan your CE calendar around your anticipated application date, not just your CHRN anniversary.
The Four Contribution Categories
Beyond hours and CE, the current advancement form requires documenting at least two of four contribution categories. This is the part of ACHRN training that most resembles genuine professional development rather than paperwork, and it's worth choosing your two categories deliberately based on your unit's opportunities.
Hyperbaric Unit Administration
Documented responsibility for operational, staffing, or quality functions within a hyperbaric unit.
- Keep job descriptions and organizational charts that name your administrative role
Teaching or Presenting Hyperbaric Lectures
Formal instruction delivered to staff, students, or professional audiences on hyperbaric topics.
- Save lecture titles, dates, audience type, and any program agendas listing you as presenter
Nursing-Care Planning or Coordination
Primary responsibility for planning or coordinating hyperbaric patient care, not incidental involvement.
- Document care-coordination protocols or case-management logs bearing your name
BNA/UHMS Officer or Committee Participation
Service in an elected, appointed, or committee role within the Baromedical Nurses Association or Undersea and Hyperbaric Medical Society.
- Keep appointment letters, meeting minutes, or committee rosters as proof
Choose the two categories where your existing role already generates natural paperwork - if you're already teaching orientation to new hyperbaric staff and coordinating care plans, those two are far easier to document than trying to manufacture a committee seat from scratch.
Fees, Timing, and Renewal Mechanics
Advancement and recertification fees vary by membership status, which is worth confirming before you assume the nonmember rate applies to you.
| Applicant Category | Fee (USD) |
|---|---|
| BNA Member | $150 |
| UHMS or ACHM Member | $200 |
| Nonmember | $250 |
ACHRN status is renewed on a four-year cycle, and renewal isn't automatic - you must maintain the advanced requirements, keep your RN licensure current, and resubmit supporting documentation each cycle. That means the tracking habits you build during your first advancement (CE logs, hour totals, contribution evidence) don't end once you're approved; they simply continue on a rolling basis so the next renewal packet is just as straightforward. For a fuller cost comparison across the CHRN and ACHRN stages, see ACHRN Certification Cost 2026: Complete Pricing Breakdown, and if you're weighing whether advancement is worth the effort and fee, Is the ACHRN Certification Worth It? Complete ROI Analysis 2026 covers that question directly.
A Practical Preparation Timeline
Because ACHRN advancement is a multi-year process rather than a single exam date, a weekly cram schedule doesn't apply the way it would to a test. What does apply is a phased approach to the CHRN exam itself, since that's the one timed assessment in this entire pathway.
CHRN Content Review
- Work through the CHRN exam domains systematically using the domains guide
- Identify weak content areas early rather than reviewing everything evenly
Timed Practice
- Run full 120-question, two-hour practice sessions on the practice test platform to build pacing
- Review missed questions against the 70% passing threshold as your benchmark
ACHRN Documentation Habits
- Start a CE and hours tracking log the day your CHRN certification is confirmed
- Identify which two contribution categories fit your current role
Notice that the "study" phase is short and CHRN-specific, while the ACHRN advancement phase is a long-running documentation habit, not a study sprint. If you want a condensed reference to keep nearby while you work through CHRN content, the ACHRN Cheat Sheet 2026: One-Page Review of Must-Know Facts is designed for exactly that.
Who Hires ACHRNs
ACHRN status signals to hyperbaric program directors, wound-care centers, and hospital-based hyperbaric units that a nurse has sustained years of hyperbaric practice, ongoing hyperbaric-specific continuing education, and demonstrated leadership beyond bedside care - whether through administration, teaching, care coordination, or professional-society service. Units expanding their hyperbaric program or seeking accreditation often look to ACHRN-credentialed staff to anchor training, protocol development, and quality oversight roles. If you're evaluating how this credential fits into a broader career trajectory, ACHRN Jobs and ACHRN Salary Guide 2026: Complete Earnings Analysis both explore that angle in more depth, and our practice test hub remains the starting point for the CHRN exam that makes advancement possible in the first place.
FAQ
No. ACHRN is an advancement from CHRN based on documented experience, hours, continuing education, and professional contributions - not a second examination. The only timed exam in this pathway is the CHRN exam.
The June 2024 resource manual permits an advanced application after three years of CHRN certification, provided the hours, CE, and contribution requirements are also met.
The advancement form requires manager or medical-director verification of at least 480 hyperbaric hours within the preceding 12 months, in addition to at least three years of overall hyperbaric experience.
You need 60 continuing education hours from the preceding four years, including at least 30 Category A hours specifically in hyperbaric oxygen therapy.
ACHRN renews every four years, requiring continued maintenance of the advanced requirements, current RN licensure, and updated supporting documentation.