16 min read
Radon inspection
How a professional radon test works, what it proves and whether it is worth it.
Read the guideShort answer
Radon certification comes from two national programs EPA recognizes, NRPP and NRSB, and from the states that license or certify radon work. Each path is an approved initial training course, an exam and an application, and your state radon program says which credential it accepts for testers and mitigators where you plan to work.
Next step: pick the right test for your home. Which test to use
Key takeaways
- EPA recognizes two national radon proficiency programs: the National Radon Proficiency Program (NRPP) and the National Radon Safety Board (NRSB).
- Some states run their own credentialing programs, and EPA's state contacts page names 20 of them. Where a state licenses radon work, the state's rule comes first.
- Both national programs follow the same outline: an approved initial training course, an exam, then an application with the documents for your devices or your supervisor.
- NRPP certifications run for two years and are renewed with continuing education; NRPP's measurement professional needs 12 credits every two years.
- A measurement technician or installer works under a certified professional or specialist. That supervision is the difference between the two tiers in both programs.
- Before you pay for a course, read what your own state says in state radon programs.
At a glance · 1 min read
Radon certification: who issues it and who needs it
Radon certification is the credential a radon tester or mitigator holds to show training and competence, and in the United States it comes from three places. EPA's page on finding a professional says states that receive indoor radon grants must list only providers credentialed through an existing state-run process, such as a state license, or through one of the two currently recognized national radon proficiency programs, which it names as the National Radon Proficiency Program (
| Issuer | What it is | What it says about the states |
|---|---|---|
| A state program | EPA: a state-run process established under a state's regulatory requirements for credentialing radon service providers, for example a state license | EPA: these programs exercise a statutory authority at the state level to oversee radon service providers |
| NRPP | NRPP: recognized by the EPA and accredited by the ANSI National Accreditation Board (ANAB) under ANSI/ISO/IEC 17024 | NRPP: consult your state's radon office to determine if your state has its own licensing program or other requirements before applying |
| NRSB | NRSB: formal recognition of professional excellence based on qualifications, high ethical standards, and continuing education in radon services | NRSB: licensing is done by the State, not by the NRSB; many states that require a license accept NRSB certification as a requirement for it |
Read moreA quote and a definition, 1 min
“Some states operate state-run credentialing programs. These programs exercise a statutory authority at the state level to oversee radon service providers by establishing and implementing requirements (e.g., licensing) to ensure radon testing and/or mitigation service providers have demonstrated and maintain sufficient professional competence.”
- National radon proficiency program
- EPA's term for the private programs it recognizes for credentialing radon service providers. EPA's page lists two: the National Radon Proficiency Program (NRPP) and the National Radon Safety Board (NRSB).
At a glance · 2 min read
NRPP radon certification: the five credentials
NRPP describes itself as recognized by the EPA and accredited by the ANSI National Accreditation Board under ANSI/ISO/IEC 17024, the standard for bodies that certify persons. It requires all certified individuals to conduct business in accordance with the applicable ANSI/AARST standards, and it says achieving and maintaining certification requires biennial documentation of competence, expertise and performance. Its types of certification page lists five credentials, each a two-year certification.
| Certification | Who it is for | Initial training NRPP requires | Supervision |
|---|---|---|---|
| Radon Measurement Professional (RMP) | Individuals who perform radon testing with an analytical device, such as a continuous radon monitor or electret system, or a standard or passive device such as a charcoal test kit | A 16-hour Radon Measurement Professional Initial Training Course, a passing score on the Measurement Professional Exam, and registration of an NRPP-approved measurement device | May supervise Radon Measurement Field Technicians |
| Radon Mitigation Specialist (RMS) | Those who evaluate radon measurements and design and install radon remediation systems | The 16-hour measurement course as a prerequisite, a 24-hour Radon Mitigation Specialist Exam-Prep Course, and a passing score on the Mitigation Specialist Exam | May supervise Radon Mitigation Installers within the same company |
| Radon Measurement Field Technician (RMFT) | Staff members who place and retrieve approved measurement devices for residential radon testing | An approved Measurement Field Technician or Measurement Professional course of at least 12 hours, and a passing score on the Measurement Field Technician Exam | Works under the general supervision and QA/QC oversight of a Certified Measurement Professional |
| Radon Mitigation Installer (RMI) | Staff members who install soil depressurization systems in residences | The 12-hour minimum measurement course as a prerequisite, a Mitigation Installer or Mitigation Specialist Exam-Prep Course of at least 20 hours, and a passing score on the Mitigation Installer Exam | Works under the general supervision of a Certified Radon Mitigation Specialist within the same company |
| Soil Gas Mitigation Compliance Inspector (SGM-CI) | Those who inspect ASD systems to verify if the installation complies with the ANSI-AARST Soil-Gas Mitigation Standard | An NRPP measurement or mitigation certification or approved relevant experience, an 8-hour SGM Compliance Inspector Initial Training Course, and a passing score on its exam | None stated |
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Radon measurement professional and technician: the difference
A paragraph and a note, 1 min
The two measurement credentials differ in responsibility, not in the kind of house they cover. NRPP says a Measurement Professional is responsible for the implementation, execution and documentation of all required QA/QC procedures and may provide general supervision and QA/QC oversight for field technicians. A Field Technician places and retrieves the devices and must work under that supervision, which is why NRPP asks a technician's application for a signed Statement of Professional Responsibility from the supervising professional. The
At a glance · 2 min read
NRSB radon certification: technician, measurement specialist and mitigation specialist
The National Radon Safety Board calls its certification formal recognition of professional excellence based on qualifications, high ethical standards, and continuing education in radon services. It certifies three kinds of individual, and it accredits radon laboratories and radon chambers. NRSB says it recognizes all ANSI/AARST radon standards in addition to the radon standards established earlier by the EPA and ASTM, and that a certificate holder must follow the standards recognized by the state in which they are conducting business.
| Certification | Initial course | Exam |
|---|---|---|
| Radon Measurement Technician (RMT) | An NRSB-approved 8-hour Initial Measurement Course | 75 multiple choice questions, with 1.5 hours to complete it |
| Radon Measurement Specialist (RMS) | An NRSB-approved 16-hour Initial Measurement Course | 100 multiple choice questions, with 2 hours to complete it |
| Radon Mitigation Specialist (RRS) | An NRSB-approved 16-hour Initial Measurement Course and a 24-hour Mitigation Course, or a combined 40-hour course | 125 multiple choice questions, with 2.5 hours to complete it |
Read moreA paragraph, 1 min
NRSB's how-to page adds the rules around those exams. A score of 70% or higher is needed for certification, the exam results are valid for one year after the date of the exam, and applicants have up to six months to complete the application process once the initial application is received. A Radon Measurement Technician is qualified to place and retrieve measurement devices, under a Quality Assurance Program supervised by an NRSB-certified Radon Measurement Specialist or an NRSB-accredited laboratory; a mitigation specialist candidate must show the ability to evaluate the quality of radon measurements, assess alternative mitigation strategies, and properly design and install effective control systems.
Step by step · 2 min read
How to get radon certification, step by step
How to get radon certification is the same outline in both national programs, and each step below is one the programs print on their own pages. Radon training comes first in both: neither program lets a candidate apply on an exam alone.
Step 1 of 6:
Read your state's rule first
NRPP's how-to page says to consult your state's radon office to determine if your state has its own licensing program or other requirements before applying. NRSB says the same: ensure that you are following all regulations in the state or states in which you will be performing radon services. Start with state radon programs.
Step 2 of 6:
Choose measurement, mitigation or both
Testing and mitigation are separate credentials in both programs. Mitigation builds on measurement: NRPP makes its 16-hour measurement course a prerequisite for the Mitigation Specialist, and NRSB asks a mitigation candidate for a minimum 16 hours of radon measurement training in addition to the mitigation course.
Step 3 of 6:
Take an approved initial training course
Take an NRPP-approved initial training course for the certification you will apply for, or an NRSB-approved initial course. NRPP says its approved courses are valid for up to two years, so the course has to be recent when you apply.
Step 4 of 6:
Pass the exam
Take and pass the program's exam for that certification. NRPP says its exams are good for up to one year when applying; NRSB says its exam results are valid for one year and that a score of 70% or higher is needed.
Step 5 of 6:
Apply with your documents
NRPP's application asks for the course completion certificate and, for a Measurement Professional, registration of every device type from its approved device list; a technician or installer names a supervisor. NRSB asks for the exam score letter, the course certificate and, for measurement, an NRSB-approved device, with a current certificate of calibration, within 12 months, for each CR device listed on the application.
Step 6 of 6:
Keep it current
NRPP says that to maintain a certification you must renew every two years, with continuing education. A certification that has been expired for more than two years means starting the certification process over.
Read moreA note, 1 min
At a glance · 3 min read
States that require radon certification or a license
EPA's state contacts page lists the states with credentialing programs to date: California, Colorado, Connecticut, Florida, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Minnesota, Nebraska, New Hampshire, New Jersey, Ohio, Pennsylvania, Rhode Island, Utah, Virginia and West Virginia. That is 20 states. The programs differ in what they issue: the state pages quoted below include a license (Minnesota), a state certification (Florida and Pennsylvania), a registration (Maine) and national certification required by state law (Virginia).
| State | What its radon program's page says | State credential required |
|---|---|---|
| Connecticut | 'The State of Connecticut does not license or otherwise certify radon professionals'; its Radon Program maintains lists of nationally certified professionals | No |
| Florida | 'Florida Statutes require the certification of businesses and individuals providing radon services or any other radon related activity'; a certified individual must work for a certified business | Yes, state certification |
| Iowa | Iowa's radon program 'approves applications for persons who wish to become certified to perform radon testing or credentialed to perform mitigation' | Yes, state certification or credential |
| Maine | 'Under Maine law, only the owner or occupant of a residence or someone registered with the state to provide these services, may test for radon, install and/or advise on the installation' of a mitigation system | Yes, state registration |
| Minnesota | 'The Radon Licensing Act requires anyone who performs a radon test or radon mitigation, in a building they do not own or lease, must be licensed by MDH. Industry or other certification is not sufficient.' | Yes, state license |
| Montana | 'Montana DEQ does not certify or require proof of certification for the contractors listed'; the individuals it lists are certified by NRPP or NRSB | No |
| Nebraska | 'If radon testing is done in schools, offices, or other places of work, it must be done by a licensed radon measurement business' | Yes, a license for that work |
| Pennsylvania | 'The Radon Certification Act requires DEP to establish by regulation, a certification program for persons conducting radon gas and radon progeny testing, laboratory analysis and mitigation of radon contamination in buildings' | Yes, state certification |
| Texas | 'There are no radon certification requirements for the State of Texas at this time' | No |
| Virginia | 'The Code of Virginia requires that Radon testers and mitigators be currently certified by either the National Radon Proficiency Program (NRPP) or the National Radon Safety Board (NRSB)' | National certification, by state law |
| Wisconsin | 'The State of Wisconsin does not require contractors performing radon measurement or mitigation work to be state licensed or nationally certified' | No |
Radon mitigation licensing: the rule is the state's
A paragraph, 1 min
Radon mitigation licensing follows the same split as testing. EPA's Consumer's Guide to Radon Reduction says many states require radon professionals to be licensed, certified or registered, and to install radon mitigation systems that meet state requirements. Pennsylvania's certification page says there are three general types of radon activities and that each type of activity requires separate certification, and Florida's says certification is divided into two parts, individuals and businesses. Minnesota's page is explicit that industry or other certification is not sufficient there.
At a glance · 1 min read
Renewal: keeping a radon certification current
NRPP's renewal page says that to maintain a certification you must renew every two years, which means completing continuing education and the other requirements for your certification and submitting the documents and fees. Continuing education courses used for a renewal must not be older than two years, and the same course may not be used for more than one renewal cycle. Since October 1, 2023, everyone holding at least one certification must also complete a standards overview course for each certification, a 4-hour course that counts toward the total.
| NRPP certification | Continuing education credits, every two years |
|---|---|
| Measurement Professional (RMP) | A minimum of 12 |
| Mitigation Specialist (RMS) | A minimum of 12 |
| Measurement Field Technician (RMFT) | A minimum of 8, Category I |
| Mitigation Installer (RMI) | A minimum of 8, Category I |
| Soil Gas Mitigation Compliance Inspector (SGM-CI) | A minimum of 4, Category I |
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Read moreA paragraph and a note, 1 min
NRPP sorts those credits into two categories. Credits for professionals and specialists come from approved continuing education programs, Category I, or from a combination of educational programs, radon conference attendance and radon public outreach efforts, Category II, with no more than 4 Category II credits in one renewal cycle. Field technicians and installers may not use Category II credits. If a certification has lapsed for less than two years, NRPP requires the Category I training for reinstatement; if it has been expired for more than two years, the candidate starts the certification process over.
Overview · 1 min read
Hiring a certified radon professional instead
If you are looking for a certified radon tester or mitigator, not for a certificate of your own, EPA's advice starts in the same place: contact your state radon program for help in finding qualified professionals in your state. EPA's Consumer's Guide to Radon Reduction recommends a certified or qualified radon mitigation contractor trained to fix radon problems, and says the first check is with your state radon office. The radon professionals directory lists measurement professionals, mitigation professionals and radon laboratories by state.
Read moreA list, 1 min
- In a state that licenses, certifies or registers radon work, ask for the state credential. NRSB's own search page says to contact the state's radon program for a complete listing of who is able to legally provide services in your area.
- In a state that does not regulate radon services, the Consumer's Guide says to ask the contractor if they hold a professional proficiency or certification credential.
- For a test in a home sale, see radon testing during a home inspection and radon inspection, which cover what a professional test involves.
Questions · 3 min read
Radon certification questions
How do I get certified to test for radon?
Take an approved initial measurement course, pass the measurement exam and apply. With NRPP that is a 16-hour Radon Measurement Professional Initial Training Course, the Measurement Professional Exam and registration of an NRPP-approved measurement device. With NRSB it is an approved 16-hour Initial Measurement Course and the Radon Measurement Specialist exam, or an 8-hour course and exam for a Radon Measurement Technician. Check your state's rule first.
How do I become a certified radon mitigator?
Mitigation certification builds on measurement training. NRPP requires its 16-hour measurement course as a prerequisite, a 24-hour Radon Mitigation Specialist Exam-Prep Course and a passing score on the Mitigation Specialist Exam. NRSB requires a 16-hour Initial Measurement Course and a 24-hour Mitigation Course, or a combined 40-hour course, and its mitigation exam. A state that licenses mitigation adds its own requirements.
What is the difference between a radon professional license and a technician license?
Supervision. In NRPP's terms a Measurement Professional is responsible for the required QA/QC procedures and may supervise field technicians, while a Measurement Field Technician places and retrieves devices and must work under that supervision. NRSB draws the same line between its Radon Measurement Specialist and its Radon Measurement Technician. A state license may use its own names for the two tiers.
Which states require radon certification or a radon license?
EPA's state contacts page lists 20 states with credentialing programs to date: CA, CO, CT, FL, IL, IN, IA, KS, KY, ME, MN, NE, NH, NJ, OH, PA, RI, UT, VA and WV. The table above quotes eleven state programs' own pages, and state radon programs links every state's.
How to become a radon inspector?
A radon inspector who tests homes holds a measurement credential: NRPP's Measurement Professional or Field Technician, NRSB's Measurement Specialist or Technician, or the state's own where the state issues one. NRPP also certifies a Soil Gas Mitigation Compliance Inspector, who inspects installed mitigation systems against the ANSI-AARST standard; that credential needs an NRPP measurement or mitigation certification or approved relevant experience, an 8-hour course and an exam.
What radon training do I need before the exam?
An approved initial course, in both programs. NRPP's hours are 16 for the Measurement Professional, at least 12 for the Measurement Field Technician, 24 for the Mitigation Specialist exam-prep course and at least 20 for the Mitigation Installer course. NRSB's are 8 for the Measurement Technician, 16 for the Measurement Specialist and 16 plus 24, or a combined 40, for the Mitigation Specialist.
What is on the radon certification exam, and is there a study guide?
NRSB's requirements overview gives the shape of its exams: 75 multiple choice questions in 1.5 hours for the Measurement Technician, 100 in 2 hours for the Measurement Specialist and 125 in 2.5 hours for the Mitigation Specialist, taken online, with 70% or higher needed. NRPP's certification FAQ says it offers online Candidate Study Guides by subscription, and NRSB's site lists a certification exams study guide.
How long does radon certification last?
NRPP's five certifications are each a two-year certification, renewed every two years with continuing education. NRSB's requirements overview lists a certification fee for one year or for two years. A state license or certification follows the state's own term.
Is NRPP or NRSB certification the one to get?
EPA names both as the two currently recognized national radon proficiency programs and ranks neither. The deciding rule is the state's: Virginia's program says its code requires testers and mitigators to be currently certified by either one, and Minnesota's says industry or other certification is not sufficient without its own license.
Can a state radon license count toward national certification?
With NRSB, yes: it says it will accept a copy of a current state radon license or a current NRPP certificate, with continuing education certificates from the current renewal period, in lieu of its initial course and exam.
Test
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