Mixed Gas Diving Supervisor Salary Guide 2026: Complete Earnings Analysis

What We Can and Cannot Say About Mixed Gas Supervisor Pay

Most salary guides invent a number and wrap a story around it. This one will not. The Mixed Gas Diving Supervisor credential, issued through the Association of Diving Contractors International (ADCI), does not come with a published pay scale, and no independently verified, credential-specific earnings dataset is available to cite. Rather than fabricate a median or a percentile range, this guide does something more useful: it explains what the credential is, what it requires, what employers are buying when they put you in the supervisor's chair, and which variables realistically move compensation up or down.

If you are weighing whether to pursue the card, treat this article as a framework for building your own estimate from real job postings, contractor conversations, and your own contract offers. For a broader cost-benefit lens, pair it with our ROI analysis of the Mixed Gas Diving Supervisor certification, and for the expense side see the certification cost breakdown.

What the Supervisor Card Actually Certifies

Compensation for supervisory roles tracks responsibility and liability. The ADCI Consensus Standards (edition 6.5) lay out exactly what a mixed-gas supervisor answers for. Section 3.6 covers supervisor duties, qualifications, and card requirements, and the list is long enough to explain why employers are selective about who they assign.

A mixed-gas supervisor carries responsibility for, among other things:

• Compliance with regulatory requirements and the employer's own manuals
• Life-support equipment readiness and immediate supervisory control of the dive
• Coordination with vessels and work sites, and selection of a suitable surface control location
• Pre-dive and post-dive checks, plus emergency and medical communications
• Job safety analysis and dive planning, including gas supply calculations
• Team duties, fitness assessment, and equipment suitability and inspection
• Current manuals, decompression tables, and treatment information on hand
• Team briefings and operation-specific procedures
• Depth, time, and gas profiles, continuous diver tending, and termination criteria
• Post-dive observation for symptoms, chamber availability, and post-treatment arrangements
• Incident reports, maintenance records, and log verification

That is the job description a client or contractor is implicitly paying for. The supervisor is the person whose judgment stands between a routine dive and a casualty, and whose paperwork is the legal record afterward. Our overview of what a mixed gas diving supervisor does goes deeper on the role itself.

The Variables That Move a Supervisor's Earnings

Since there is no published scale, think in terms of drivers. The table below describes the qualitative factors that shape what supervisors are offered, without attaching invented numbers.

Notice what the table does not say: it does not claim that one factor outweighs the others by some percentage. In practice, the supervisor who is assignable to the widest range of projects and trusted by the employer usually has the strongest negotiating position, but how that translates into dollars is something you must confirm in your own market.

The Path to the Card: Time Invested Before Pay Rises

A salary conversation about this credential has to account for the years it takes to become eligible. The requirements are substantial, and they define who is even in the candidate pool. Our full requirements and eligibility guide covers each item, but the headline prerequisites are:

• Passing the specific ADCI HeO2/mixed-gas supervisor examination
• At least 350 field days as an air or mixed-gas diver
• 150 working dives
• 30 working days as an assistant mixed-gas supervisor
• Prior qualification as an air-diving supervisor
• Employer vetting and a written assignment
• A mode-specific supervisor card
• Medical fitness before hyperbaric exposure
• Valid CPR and first aid

Because the card is tied to employer vetting and a written assignment, your employer's willingness to put you forward is part of the gate. That makes your relationship with your current contractor a career asset, not just a job detail.

The Cost Side of the Ledger

The issuer's certification page lists an online exam as required and shows $275 for the supervisor card category. That is the figure to anchor on, with an important caveat: it should not be read as an independently verified exam-only fee, and the page's own wording is the controlling source. Confirm current pricing directly with ADCI before budgeting, and see the complete pricing breakdown for how to think about the surrounding costs.

Beyond the listed card category, your real investment includes items the fee does not capture:

• Preparation materials and practice time
• Medical fitness evaluation required before hyperbaric exposure
• CPR and first aid renewal to keep those certifications valid
• Any time away from paid work if you must travel for training or assessment

Set against the multi-year field experience the standard demands, the card fee itself is small. The meaningful economic question is not the $275 category; it is whether the supervisory assignments the card unlocks justify the years of dives and assistant-supervisor days that precede it.

Who Hires Mixed-Gas Supervisors

Mixed-gas diving, meaning surface-supplied HeO2 work, is used where depth or conditions call for a breathing mix rather than air. Supervisors holding the relevant card are staffed by organizations that run such operations. In general terms that includes commercial diving contractors, offshore and marine construction firms, and companies handling inspection, repair, and salvage tasks at depth. Our mixed gas diving supervisor jobs page explores the employer landscape in more detail.

One point worth stressing: the standards require employer vetting and a written assignment. In other words, the card alone does not authorize you to supervise a given job. Your employer has to assign you in writing, which means hiring managers are evaluating both the credential and their own confidence in you. That dynamic shapes how supervisors are recruited and retained, and it is a reason continuity with a trusted contractor can matter as much as the card itself.

Why Exam Mastery Connects to Earning Power

The exam is a gate, but it is also a proxy for the judgment the job demands. Our preparation materials map the source standards into five study groupings. Note that these are editorial selections drawn from the published standards, not an official weighted blueprint, and the question count, time limit, and passing score are not established. For what is and is not known, see the passing score discussion and the pass rate analysis.

For a domain-by-domain walkthrough, see the complete guide to all five content areas. The link to earnings is indirect but real: a supervisor who can plan a gas profile, run a clean dive, and handle an umbilical or breathing-media emergency is the supervisor an employer wants to keep assigning.

Sequencing Your Preparation Around the Five Domains

You do not need a generic study system here. A sensible order follows how the standards build on one another, and the full approach is in our study guide for passing on your first attempt. One compact way to schedule the five groupings:

Emergencies come last because they draw on everything else: you cannot reason through a lost-communications scenario without knowing the equipment, the procedures, and your own duties. When you are ready to test yourself, the Mixed Gas Diving Supervisor practice tests let you drill each grouping. If you want a realistic sense of how demanding it is, read how hard the exam is.

Negotiating From the Credential

Because no verified salary table exists, your leverage comes from specifics you can demonstrate. A few practical angles:

1. Document your path. Keep clean records of field days, working dives, and assistant-supervisor days. Those are the exact thresholds the standard names, and they are the evidence an employer's vetting process will look for.
2. Know which modes your employer staffs. A mode-specific card only pays off if the contractor runs that kind of work. Ask what share of their projects involve surface-supplied mixed gas.
3. Clarify the assignment process. Since written assignment is required, ask how and when employers issue it, and whether your role is a staff position or project-based.
4. Compare structures, not just headline rates. Day rates, rotations, standby treatment, and benefits can change what an offer is really worth.
5. Treat your records as an asset. Your logs, maintenance records, and incident history are part of your professional reputation. Accurate verification is a core supervisor duty under section 3.6.

If you are still deciding between credentials or still learning the terminology, our explainer on the Mixed Gas Diving Supervisor certification is a good starting point, and the exam dates and scheduling guide covers timing questions.

Frequently Asked Questions