RMI Requirements 2026: Eligibility, Prerequisites & How to Qualify

What "Qualifying" Means for a Radon Mitigation Installer

The Radon Mitigation Installer (RMI) credential, issued through the National Radon Proficiency Program (NRPP), is an entry-level, supervised certification. That single word, supervised, shapes nearly every requirement in this guide. Unlike credentials for independent specialists, the RMI is designed for the person physically installing systems under the oversight of a more senior, certified professional.

That distinction matters for how you read the rules. Qualifying is not just a matter of passing a test. You assemble a package: approved training, a passing exam result, a signed ethics document, and a workplace relationship with a certified supervisor. Miss any one piece and the certification does not issue.

This article covers the RMI credential only. It does not cover the Radon Measurement Specialist, the Radon Measurement Professional, or state licensing, all of which have their own rules. If you are still orienting yourself, start with What Is RMI Certification? before returning here for the requirement details.

The Prerequisite Checklist

NRPP publishes its prerequisites on its certification types page. For the RMI, the pieces are:

Notice what is not on the list: there is no minimum education level, no apprenticeship log, and no required years of field experience. The credential is built so a motivated newcomer can enter the trade, provided a certified supervisor stands behind them.

Measurement and Mitigation Training Hours

Two blocks of approved coursework form the educational foundation of the credential. The measurement training (at least 12 hours) teaches you how radon is detected, tested and interpreted. The mitigation training (at least 20 hours) covers how systems are designed and installed to reduce radon levels in a building.

Two practical points are worth knowing before you enroll:

• Approval matters. The hours must come from a course NRPP recognizes. A general building-trades class that touches on ventilation will not satisfy the requirement.
• Training cost is separate. The NRPP exam and certification fees do not include tuition. Course pricing varies by provider, so budget for it independently. Our RMI certification cost breakdown lays out how the pieces fit together.

For a closer look at what these courses typically cover and how to choose one, see our overview of RMI training.

Supervision by an NRPP-Certified RMS

The supervision requirement is the feature that most clearly separates the RMI from other radon credentials. To hold RMI certification, you must work under an NRPP-certified Radon Measurement Specialist (RMS) who is employed by the same company you are.

Three consequences follow:

1. You generally need an employer first. Because the supervisor must be at your company, a freelancer with no certified RMS relationship cannot simply self-certify as an RMI.
2. Documentation is ongoing. Current supervisor documentation is part of renewal, so the relationship is not a one-time checkbox.
3. Policy details can change. NRPP published supervisory policy changes in August 2025. Review that update directly, and confirm the current language with NRPP before you plan your hiring or staffing around it.

Keep in mind that the NRPP supervision requirement is separate from any supervision or licensing rules your state imposes. Those are addressed in the state section below.

Validity Windows: Training and Exam Results

Two documents in your qualification package have expiration clocks, and mismanaging them is one of the most avoidable ways to lose time and money.

The practical takeaway: do not pass the exam and then let the rest of your package sit. If your exam result is valid for one year, you have a defined window to finish assembling everything else, including your supervisor relationship and signed statement. Likewise, training taken more than two years before you apply may no longer count.

Exam Day Requirements and Conditions

Passing the exam is itself a prerequisite, so the testing conditions are part of the qualification process. Current delivery is through Certiverse with live remote proctoring, which replaced the older Examity delivery described in the handbook.

Format and Timing

The exam delivers 95 questions in total: 85 are scored and 10 are unscored trial items used to evaluate future questions. You will not know which are which, so treat every question as if it counts. You have a two-hour testing limit. This structure has applied since October 1, 2024. The handbook's older 85-total-item statement is outdated.

What You Need to Test

• Photo ID that you will present to the proctor.
• A live proctor and a room scan as part of check-in.
• A suitable testing space, since you are being observed remotely.

What Is and Is Not Provided

The testing platform provides SGM-SF-2023, MAH-2023, a calculator and formulas in-platform. This does not mean you can bring personal reference books; the resources available are the ones built into the exam interface. Familiarize yourself with those references ahead of time so you are not hunting through unfamiliar material under a two-hour clock.

Breaks and Retakes

One bathroom break of up to five minutes is permitted. If you do not pass, retakes require a 30-day wait, with at most four attempts in 12 months. Because a failed attempt costs both the fee and a month, preparation before the first sitting is worth the investment. Our RMI difficulty guide and pass rate analysis discuss what to expect, and the passing score article explains how the issuer's competency standard works without an unsupported numeric cutoff.

Fees Tied to Qualification

NRPP's fee schedule, effective January 1, 2025, sets the amounts that apply to RMI candidates:

All three are separate from training tuition. A candidate qualifying for the first time therefore pays the exam fee to test and the certification fee once the full package is approved, on top of whatever the two training courses cost. If a retake is needed, factor in another exam fee. For the full picture, including how to weigh these costs against earning potential, see the pricing breakdown and the ROI analysis.

What the Exam Will Test Once You Qualify

Meeting the eligibility rules gets you to the exam; the six official content domains determine whether you pass. These headings and weights come from Appendix A of the NRPP Candidate Handbook (V7, revised May 4, 2023), and they total 100%.

Domain 4 alone is nearly a third of the exam, so it deserves a proportionate share of your preparation. For a full walkthrough of what each area covers, read the RMI exam domains guide.

Keeping the Credential: Renewal Requirements

Qualifying is not the end of the requirements. Certification lasts two years, and renewal has its own checklist:

• Eight Category I continuing education hours, including the applicable four-hour Standards Overview course.
• Ethics compliance, consistent with the professional responsibility you committed to at the start.
• Current supervisor documentation, confirming the supervision relationship remains in place.
• The $250 renewal fee.

The mandatory Standards Overview course is a recurring obligation, not a one-time item, so build it into your calendar well before your two-year cycle ends. NRPP maintains a dedicated page for this requirement and for recertification steps.

A Sensible Order of Operations

Because each requirement has a validity window, the order in which you tackle them matters. Here is one practical sequence, tied to the specifics above rather than generic scheduling advice:

If you want a realistic read on your readiness before paying the exam fee, a timed run through the RMI practice tests is a low-cost way to find weak domains first. For scheduling specifics and testing windows, see the RMI exam dates guide.

State Licensing Is a Separate Question

NRPP certification and state licensing are not the same thing. Many states regulate radon professionals independently, and their requirements can differ from NRPP's in training hours, supervision, fees and recognition of national credentials. Some states accept NRPP certification as part of their own process; others layer additional steps on top.

Likewise, the supervision rule described earlier is an NRPP requirement. Your state may impose its own supervision or licensing conditions, which are separate from and in addition to the NRPP rules. Before you invest in training, check with your state's radon or environmental health program to learn exactly what applies where you plan to work. This article intentionally does not state any individual state's rules, because those vary and change.

Frequently Asked Questions

Now that the eligibility picture is clear, the next step is preparing for the exam itself. Our RMI cheat sheet condenses the must-know facts, and the salary guide shows what the credential can mean for your earning potential once you qualify.