The RMS exam is the National Radon Proficiency Program (NRPP) test for people who install radon mitigation systems and have finished an NRPP-approved initial training course. This page gives you free practice sets by topic, worked explanations of sample questions, the verified exam facts (165 questions in 3 hours, $175, taken online with Certiverse proctoring) and a study plan. We write this content with AI tools, so check the details at nrpp.info.
The RMS has 165 questions, takes about 3 hours and costs $175[1][2] (National Radon Proficiency Program, verified Oct 25, 2026).
Numbers in brackets link to the official sources listed under Sources & last verified. Dates that have passed are removed automatically.
| Item | Detail | Source · Verified |
|---|---|---|
| Number of questions | 165 questions (150 scored + 15 unscored)[1] | National Radon Proficiency Program · Oct 25, 2026 |
| Time limit | 3 hours[2] | National Radon Proficiency Program · Oct 25, 2026 |
| Exam fee | $175 per exam (non-refundable)[2] | National Radon Proficiency Program · Oct 25, 2026 |
| Retake policy | 30-day wait between attempts; max 4 in 12 months[3] | National Radon Proficiency Program · Oct 25, 2026 |
| Validity | Exam score good up to 1 year when applying[4] | National Radon Proficiency Program · Oct 25, 2026 |
| Delivery | Online, live remote proctoring via Certiverse[1] | National Radon Proficiency Program · Oct 25, 2026 |
| Eligibility | NRPP-approved initial training course, then pass the NRPP exam[4] | National Radon Proficiency Program · Oct 25, 2026 |
| Registration deadline | Schedule and complete within 30 days of registration[2] | National Radon Proficiency Program · Oct 25, 2026 |
According to National Radon Proficiency Program, “Starting October 1, 2024 the RMS exam will consist of 165 questions:”[1]
The RMS exam is the National Radon Proficiency Program (NRPP) test for Radon Mitigation Specialists. Passing it is one of the steps in applying for NRPP certification to design and install radon mitigation systems.
Eligibility. You first take an NRPP-approved initial training course for the RMS certification, then you take the exam. A passing exam is good for up to 1 year when you apply for NRPP certification, so plan to send your application soon after you pass.
Format and delivery. Starting October 1, 2024, the RMS exam has 165 questions: 150 scored and 15 unscored. You get 3 hours. All NRPP exams are proctored remotely online by a live proctor through Certiverse. Before exam day, read Certiverse's computer and room requirements.
Fee and scheduling. The exam costs $175 and the fee is non-refundable. You must schedule and finish the exam within 30 days of registering, or you may owe late fees.
Retakes. NRPP requires a 30-day wait between attempts and allows no more than 4 attempts in a 12-month period.
Some states have their own radon licensing rules in addition to NRPP certification, so also check with your state radon program. NRPP can change its fees and policies, so confirm the current details on the official NRPP site before you register.
Prepare for the RMS - Radon Mitigation Specialist exam with our free practice test modules. Each quiz covers key topics to help you pass on your first try.
These are practice questions written for this site, not questions from the real exam. Each explanation shows why the right answer is right and why the others are wrong.
Question: Under AARST-ANSI standards, what is the minimum required warranty period an RMS must offer for a sub-slab depressurization system?
Answer: B. 1 year
Explanation:
B, 1 year is the correct answer. The mitigation standards used in NRPP training expect the installer to warrant the system's workmanship for at least 1 year. A shorter term falls below that minimum. A, 6 months is too short to meet it. C, 2 years and D, 5 years are terms a contractor may choose to offer. The question asks for the minimum, though, and a longer warranty is a business decision, not the requirement. The rule to remember: when a question asks for a minimum required value, choose the lowest value the standard allows, not what good practice or marketing might add. Warranty wording can differ between editions of the standards and between state rules, so check it in the current standard your training course uses.
Question: How do RMS professionals contribute to organizational success?
Answer: A. By applying specialized knowledge to solve problems, reduce risks, improve processes, and drive strategic outcomes
Explanation:
A is correct because it names specific ways a trained mitigator adds value. Examples include working out why a system is underperforming, lowering occupants' radon exposure and the company's liability, and making installation and documentation more consistent. B is wrong because mitigation work calls for judgment on every site, so it is not just a routine task. C is wrong because it dismisses specialist knowledge, which is the reason certification exists. D is wrong because contribution does not depend on job title, and field staff shape results directly. The rule to remember: in professional-practice questions, options built on absolutes such as only, no or minimal are usually wrong. Choose the option that describes concrete, practical value.
Question: What is the importance of professional networking in radon mitigation?
Answer: A. Building relationships with peers enables knowledge sharing, professional development, and career advancement
Explanation:
A is correct because contact with peers is how mitigators share field problems and fixes, learn about changes to standards and state rules, and find mentors and work opportunities. B is wrong because experienced professionals still need to keep up with revised standards and new techniques, and peers are one of the main ways they hear about them. C is wrong because in-person events, training courses and local trade contacts are also valuable, so value is not limited to online networking. D is wrong because people at every career stage benefit. Newer staff gain guidance, and experienced staff gain referrals and updates. The rule to remember: answers that limit a good practice to one group or one channel are usually wrong. Choose the answer that describes the practice's broad, practical benefit.
Use the materials from your NRPP-approved training course and the mitigation standards it teaches as your main source. Many RMS questions test what the standard requires, not general opinion. Use the practice sets here to find gaps, then close them with those materials.
The RMS exam has 165 questions and a 3-hour time limit. Starting October 1, 2024, 150 of those questions are scored and 15 are unscored. The unscored questions are mixed in with the others, so answer every question carefully and pace yourself to finish all 165 in the time allowed.
The exam fee is $175, and NRPP does not refund it. After you register, you must schedule and finish the exam within 30 days to avoid extra late fees. Fees can change, so check the current amount on the official NRPP exams page before you pay.
Yes. All NRPP exams are proctored remotely online by a live proctor through a platform called Certiverse. Before exam day, read Certiverse's requirements for your computer, internet connection and testing room so that a setup problem does not cost you your exam slot.
You need to finish an NRPP-approved initial training course for the RMS certification first, then pass the NRPP exam. Your state may also have its own radon licensing rules, so check with your state radon program and the official NRPP site to see what applies where you work.
You can retake it, but NRPP requires a 30-day wait between attempts and allows no more than 4 attempts in a 12-month period. The fee is $175 per exam. Use the waiting period to review the topics where you lost points in your course materials and the matching practice sets.
A passing exam is good for up to 1 year when you apply for NRPP certification. If you wait longer than that to apply, you may need to take the exam again. Plan to send your certification application soon after you pass.
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