A Radiation Safety Officer (RSO) is the individual an institution designates to hold day-to-day responsibility for its radiation protection program under a U.S. Nuclear Regulatory Commission (NRC) or NRC Agreement State radioactive-materials license. Where the Radiation Safety Committee (RSC) is the deliberative body that authorizes uses and users under a broad scope or multi-modality license, the RSO is the named, operational role the license itself depends on: the person who runs surveys, reviews dosimetry, manages waste, investigates incidents, and is legally accountable to the regulator for the program’s day-to-day compliance. This guide covers who must appoint an RSO, what the role’s duties and authority actually are, how RSO qualification requirements work, and how the role relates to the RSC and to an institution’s other safety-officer positions.
What Triggers the Requirement to Designate an RSO
Any institution or facility that holds an NRC or Agreement State license authorizing the possession and use of byproduct, source, or special nuclear material must name a Radiation Safety Officer on that license — this is a universal condition of holding a materials license, not something limited to institutions large enough to need a full committee. An Agreement State is a state that has entered into an agreement with the NRC under Section 274 of the Atomic Energy Act to regulate byproduct, source, and certain quantities of special nuclear material within its borders in place of the NRC; most Agreement States adopt requirements compatible with the NRC’s own rules, so an RSO’s duties and the citations below are typically substantively similar across both, though an institution in an Agreement State should confirm its specific obligations against that state’s regulations.
Whether the RSO operates alone or alongside a standing RSC depends on the license type:
- Broad scope specific licenses (10 CFR 33.13) — issued to institutions running many different protocols, isotopes, and users, typically research universities and academic medical centers — require both a named RSO and an RSC composed of the RSO, a management representative, and persons trained and experienced in the safe use of radioactive material.
- Medical use licenses authorizing two or more types of use spanning the modality subparts of 10 CFR Part 35 (10 CFR 35.24) also require an RSC, on which the RSO is a required member alongside an authorized user for each use type, a nursing-service representative, and a management representative who is neither an authorized user nor the RSO.
- Limited scope or single-modality licenses — a single department using one isotope for one defined purpose — may not require a standing committee at all; the RSO alone can carry the program’s day-to-day responsibility, reporting directly to institutional management and the license holder.
License Type and RSO/RSC Requirement
| License type | RSC required? | Governing citation | Typical setting |
|---|---|---|---|
| Broad scope specific license | Yes | 10 CFR 33.13 | Research university or academic medical center with many protocols/isotopes |
| Medical use license, multiple modality types | Yes | 10 CFR 35.24 | Hospital or academic medical center with nuclear medicine plus another modality |
| Limited scope / single-modality license | No — RSO alone | Applicable subpart of 10 CFR Part 35 or Part 33 for that specific use | Single department or single-isotope research or clinical use |
| Agreement State license | Varies — generally mirrors the federal trigger above | State regulations adopted under Section 274 of the Atomic Energy Act | Most U.S. states hold Agreement State status |
The presence of a standing RSC is itself a signal that an institution holds a broad scope or multi-modality license; its absence does not mean the institution lacks radioactive-material oversight, only that the RSO is carrying that responsibility without a standing committee.
Core RSO Responsibilities
Across license types, the duties that define the role are consistent:
- Program management. Implementing and maintaining the institution’s radiation protection program to the standard the license and the RSC’s (where one exists) approved criteria require.
- Radiation surveys. Performing or supervising area and equipment surveys to confirm contamination and exposure levels remain within license limits.
- Dosimetry oversight. Reviewing personnel dosimetry badge results, investigating any reading approaching an action level, and maintaining the dose records the license depends on.
- ALARA implementation. Applying and enforcing As Low As Reasonably Achievable (ALARA) practice — time, distance, and shielding controls — across all authorized uses.
- Waste management. Overseeing segregation, decay-in-storage, and disposal of radioactive waste in accordance with license conditions.
- Training. Providing or arranging radiation safety training for authorized users and ancillary personnel before they begin working with licensed material.
- Incident investigation and reporting. Investigating overexposures, contamination events, and lost-source incidents, and making the regulatory notifications the license and 10 CFR Part 20 require.
- Corrective action and stop-work authority. Directing corrective action when a survey, incident, or audit reveals noncompliance, including the authority to suspend an individual user’s authorization to work with radioactive material pending correction.
- Recordkeeping. Maintaining the survey records, dose records, inventory records, and authorization records an NRC or Agreement State inspector examines to confirm the license’s administrative conditions are being met.
RSO Qualification and Training Requirements
How an individual qualifies to serve as RSO depends on the license type, and there is no single hours-based rule that applies uniformly across every license:
For medical use licenses, 10 CFR 35.50 sets out two qualifying pathways. An individual can qualify by being certified by a medical specialty board whose certification process the NRC or an Agreement State has recognized, having passed an examination assessing knowledge and competence in clinical radiological or nuclear medicine physics and in radiation safety. Alternatively, an individual can qualify through a structured educational program consisting of 200 hours of classroom and laboratory training covering specified radiation-safety subject areas, plus one year of full-time radiation safety experience under the supervision of an individual already named as RSO on a Commission or Agreement State license — including hands-on work in shipping and receiving, radiation surveys, instrument checks, contamination-control and decontamination procedures, and emergency procedures — documented by a written attestation from a preceptor RSO.
For broad scope research licenses under Part 33, there is no single codified hours-based training standard equivalent to 10 CFR 35.50; instead, the license applicant identifies the proposed RSO’s training and experience in the license application itself, and the NRC or Agreement State reviewer evaluates that individual’s qualifications against the specific isotopes, activities, and uses the license will authorize before approving the license. Institutions preparing an application or an RSO-change amendment should consult their NRC regional office or Agreement State agency directly on what documentation a given license review will expect, rather than assume the medical-use pathway above applies verbatim to a research license.
The RSO’s Relationship to the Radiation Safety Committee
Where a license requires a standing Radiation Safety Committee, the RSO is always a required member, and in practice the RSO usually plays the lead operational role on the committee — bringing survey data, incident reports, and dose records to each meeting and executing the corrective actions the committee directs. Neither 10 CFR 33.13 nor 10 CFR 35.24 requires the RSO to chair the committee, however, and many institutions deliberately name a separate management representative or senior faculty member as chair to preserve a distinction between the RSO’s day-to-day operational authority and the committee’s independent oversight authority over that program. The RSC reviews and can override or add conditions to what the RSO authorizes; the RSO cannot use RSC membership to bypass the committee’s own approval criteria for new uses and users under a broad scope license.
What an RSO Can Decide Alone, and What Requires the Committee or the License Itself
An RSO’s independent authority is real but bounded. Acting alone, an RSO can typically halt an unsafe practice, suspend an individual’s day-to-day authorization to work with radioactive material pending investigation, order additional surveys or decontamination, and direct immediate corrective action after an incident — authority that follows from the RSO’s role as the person legally accountable for the program’s compliance. What an RSO generally cannot do alone is authorize a genuinely new use, isotope, or user under a broad scope license (that requires RSC review against the committee’s approved criteria) or expand what the license itself permits (that requires an NRC or Agreement State license amendment). This division — RSO for operational and emergency authority, RSC for new-use authorization, the license and its issuing regulator for anything the license doesn’t already cover — is the same structure that governs how the RSC itself functions.
Where the RSO Role Overlaps with Other Institutional Safety Officers
At smaller institutions, the RSO role is sometimes combined with other safety-officer functions held by the same Environmental Health & Safety (EH&S) professional — most commonly with the Biosafety Officer (BSO) role, and less commonly with the Chemical Hygiene Officer (CHO) role. Each of these three positions exists because a different regulatory framework requires it — the RSO under an NRC or Agreement State radioactive-materials license, the BSO under the NIH Guidelines for institutions doing recombinant or synthetic nucleic acid research, and the CHO under OSHA’s Laboratory Standard, 29 CFR 1910.1450 — and each answers to a different regulator over a different hazard category even when one person holds more than one title. Institutions with BSL-3/BSL-4 facilities, large-scale radioisotope use, or high research volume generally treat each as a dedicated full-time role given the volume of inspection, survey, and training work involved; smaller institutions more often combine them.
Frequently Asked Questions
Is the Radiation Safety Officer the same as the Radiation Safety Committee?
No. The RSO is a single named individual with day-to-day operational responsibility for the radiation protection program. The RSC, where a license requires one, is a multi-member committee that reviews and authorizes new uses and users and oversees the RSO’s program on a periodic basis. The RSO is a required member of the RSC when one exists, but the two are legally distinct — see CASRAI’s Radiation Safety Committee (RSC) entry for how the committee itself is structured.
Does every institution that uses radioactive material need a full-time RSO?
Every license requires a named RSO, but not every RSO is a full-time, dedicated position. Institutions with a limited scope or single-modality license, low research volume, or a small inventory of licensed material commonly assign the RSO role to an EH&S professional as part of a broader safety portfolio, sometimes combined with the Biosafety Officer or Chemical Hygiene Officer role. Institutions with broad scope licenses, BSL-3/BSL-4 facilities, or high-volume radioisotope programs typically make it a dedicated, full-time position.
Can one person hold the RSO, BSO, and CHO roles at the same time?
Regulatorily, yes — none of the three frameworks (NRC/Agreement State licensure, the NIH Guidelines, or OSHA’s Laboratory Standard) prohibits combining the roles in one person, and smaller institutions frequently do. The tradeoff is one of capacity and expertise rather than legality: each role requires its own qualification pathway and carries its own inspection, survey, and training workload, so institutions combining the roles need to confirm the individual can genuinely meet all three sets of qualification requirements and sustain all three workloads, not just hold all three titles.
What happens if an institution’s RSO leaves or is not qualified?
A license’s RSO designation is a named condition of that license, so a departure or a change in who fills the role generally requires notifying the NRC or Agreement State and, in many cases, filing a license amendment naming the new RSO and documenting that individual’s qualifications before that person can act as RSO of record. Institutions typically identify and begin qualifying a successor, or use a documented Associate RSO arrangement where the license and 10 CFR 35.50 (for medical use licenses) permit one, well before a planned departure to avoid a gap in the license’s required staffing.
Related CASRAI resources: Radiation Safety Committee (RSC), ALARA: Time, Distance, Shielding, How Dosimetry Badges Work, Radioactive Waste Disposal in the Lab, Biosafety Officer (BSO): Role and Responsibilities, and The Chemical Hygiene Officer Role.
