NRC Reciprocity: Form 241 Across State Lines

NRC reciprocity is how an Agreement State licensee legally performs its licensed work outside its home state without holding a second full license. Under 10 CFR 150.20, a general license plus an NRC Form 241 authorizes temporary work in areas of NRC jurisdiction, while work in another Agreement State runs through that state's own reciprocity process. The details—where to file, the fee, the 180-day limit, and what reciprocity does not cover—decide whether a traveling program is compliant or in violation.

For a consulting medical physicist, a mobile nuclear medicine service, a portable-gauge operator, or any program that crosses state lines with licensed radioactive material, one question controls compliance: am I authorized to do this work here? A specific radioactive material license is jurisdiction-bound—it authorizes activity within the state (or NRC region) that issued it. Reciprocity is the bridge that lets that authorization travel, temporarily and under conditions.¹²

This guide explains what reciprocity is, when NRC Form 241 applies versus an Agreement State's own process, how to file, the limits and fees, the 2025 changes to the filing timeline, and how a multi-state program keeps it all straight. DRPS relies on this framework every week across its ten-state footprint, and provides radioactive material license support and radiation safety officer services to facilities and traveling programs alike.

Introduction

Reciprocity exists because the United States regulates radioactive material through a patchwork of authorities, and licensed work routinely crosses their boundaries. The NRC directly regulates byproduct material in non-Agreement States, federal facilities, and offshore waters. Forty Agreement States (as of 2025, with Connecticut the most recent) regulate it themselves under Section 274 of the Atomic Energy Act. A license from any one of these authorizes work in that jurisdiction—not everywhere.²⁷

Without reciprocity, a physicist licensed in Florida who wanted to survey a facility in Washington, DC (an area of NRC jurisdiction) would need a separate NRC license. Reciprocity replaces that burden with a general license and a notification: file NRC Form 241, meet the conditions, and you may do the same work you are licensed to do at home, temporarily, in the new jurisdiction.¹³

This article walks through the legal mechanism, the critical "who do I file with" decision, the filing package and fee, the 180-day limit, a worked example of a practical calculation a traveling program actually performs, the compliance stakes, and the regulatory context—including the 2025 modernization of the filing timeline.

Topic Explanation

What reciprocity is—and what it is not

Reciprocity is a general license, granted by rule, that recognizes a specific license issued by another authority for temporary work. Under 10 CFR 150.20, any person who holds a specific license from an Agreement State—where the licensee maintains the office that directs the licensed activity and keeps its radiation safety records—is granted a general license to conduct that same activity in areas of NRC jurisdiction, provided the specific license does not restrict the activity to specified installations or locations.¹

That definition carries important limits built into the words:

• Same activity. Reciprocity lets you do what your specific license already authorizes—no more. It does not expand your scope.
• Temporary. It is for temporary jobsites, not a permanent presence, and it is capped in time (see the 180-day limit below).
• Not a distribution or transfer authority. It is not a route to sell, transfer, or leave radioactive material in the new jurisdiction.
• Location-restricted licenses do not travel. If your specific license limits the activity to named locations, the 150.20 general license does not apply.¹

For the foundational picture of how a specific license is structured in the first place, see our NRC materials license guide and the radiation safety officer role.

The decision that trips people up: who do I file with?

The single most common reciprocity mistake is filing with the wrong authority. The rule is simple once stated: you seek recognition from the authority that regulates the place where the work will happen.

• Work in an area of NRC jurisdiction (a non-Agreement State, a federal facility or other area of exclusive federal jurisdiction, or offshore waters) → file NRC Form 241 under 10 CFR 150.20.
• Work in a different Agreement State → file under that state's reciprocity process, not NRC Form 241.

This matters enormously for a multi-state program, because most states are Agreement States and each runs its own reciprocity procedure, fee, and timeline. NRC Form 241 is only your instrument when the destination is NRC territory.¹³⁴

The table below maps this for the ten jurisdictions DRPS serves, from the perspective of an Agreement State licensee (for example, a Florida-licensed program) traveling to each.

Two of DRPS's jurisdictions—Washington, DC and Delaware—are regulated directly by the NRC, so a traveling Agreement State licensee working there files NRC Form 241. The other seven states are Agreement States, each with its own reciprocity route. Note that X-ray machine work is regulated separately (by the states as radiation-producing machines and by the FDA), so this reciprocity framework applies to byproduct (radioactive) material, not to X-ray equipment.¹²

Key Technical Principles

The filing package, the fee, and the 180-day limit

To invoke the 10 CFR 150.20 general license for the first time in a calendar year, an Agreement State licensee files with the NRC Regional Administrator for the region in which the Agreement State that issued its license is located:¹³

• a completed NRC Form 241, "Report of Proposed Activities in Non-Agreement States, Areas of Exclusive Federal Jurisdiction, or Offshore Waters";
• a copy of the Agreement State specific license; and
• the fee specified in Fee Category 16 of 10 CFR 170.31.⁵

Changes after the initial filing—new work locations, different radioactive material, or different activities—require an amended NRC Form 241 to the Regional Administrator.¹³

Activities conducted in NRC jurisdiction under this general license, other than in offshore waters, are limited to 180 days in any calendar year.¹ A program that needs a sustained or long-term presence in an area of NRC jurisdiction should plan for a specific NRC license rather than stretching reciprocity past its intent.

The 2025 change to the filing timeline

Historically, the initial NRC Form 241 had to be filed at least three days before the licensee began work in NRC jurisdiction. In 2025, under Executive Order 14300 ("Ordering the Reform of the Nuclear Regulatory Commission"), the NRC moved to reduce that lead time so that an initial Form 241 could be filed as late as the day work begins, and it issued interim staff guidance to implement the change while a broader modernization of its byproduct-material regulations proceeds.⁸⁹ Because that implementation was still settling as this was written, a traveling program should confirm the current filing deadline and regional expectations directly with the appropriate NRC regional office before relying on same-day filing. Reducing a required lead time does not reduce the importance of filing correctly and completely.

A calculation traveling programs actually run: decay-correcting the check source

Reciprocity work is often survey, calibration, or measurement work, and a physicist who travels to a jobsite typically carries a sealed check source (for example, Cs-137) to verify instrument response. That source's activity must be decay-corrected before it can be used as a reference, because it has been decaying since its certificate date. The governing relationship is exponential decay:

$$A(t)=A_0{e}^{-\lambda t}=A_0{\left(\frac{1}{2}\right)}^{t/T_{1/2}},\lambda =\frac{\ln 2}{T_{1/2}}$$

Consider a Cs-137 check source ($T_{1/2}\approx 30.08$ years) certified at $A_0=3.70$ MBq (100 µCi), now 6.0 years past its certificate date. The decayed activity is:

$$A=3.70\times {\left(\frac{1}{2}\right)}^{6.0/30.08}=3.70\times 0.871\approx 3.22\text{MBq}$$

So the reference is about 3.22 MBq (≈ 87 µCi), not the 3.70 MBq on the label—an ~13% difference that would bias every instrument-response check if ignored. The same discipline applies to any transported source under reciprocity: know its current activity, keep it within your license's possession limits, and transport it in compliance with U.S. Department of Transportation rules. See our guide to transport of radioactive material under DOT 49 CFR.

Clinical Impact

For a multi-state medical physics or nuclear medicine program, reciprocity is not paperwork trivia—it is the difference between authorized and unauthorized possession and use of radioactive material. Performing licensed work in a jurisdiction without the proper reciprocity recognition or specific license is a violation that can draw a notice of violation, a civil penalty, or enforcement against the underlying license.³⁴

The practical impact shows up in scheduling and program design. A consulting physicist covering ten jurisdictions cannot treat "I'm licensed in Florida" as blanket authorization. Each destination has to be mapped to the correct regulator, each filing has to be current for the calendar year, and each amendment (a new site, a new source) has to be submitted before the work. The 180-day limit forces a program that keeps returning to the same NRC-jurisdiction site to decide whether reciprocity still fits or whether a specific license is now the right vehicle.¹

There is also a records dimension. The 150.20 general license is premised on the home office being where the licensed activity is directed and where radiation safety records are kept. A program that lets that structure blur—directing work from a satellite location, keeping records inconsistently—can undermine the very basis of its reciprocity. Clean license administration, of the kind covered in preparing for an NRC inspection, is what makes a traveling program defensible.

Practical Optimization Tips

A traveling program keeps reciprocity clean with a few disciplined practices.

1. Map every work location to its regulator before scheduling

Build a simple lookup: for each planned jobsite, is it NRC jurisdiction (file Form 241) or an Agreement State (use that state's process)? Do this at scheduling time, not the week of the job, because Agreement State processes and timelines vary.³⁴

2. File early even where same-day filing is now allowed

The 2025 change reduced the required lead time, but earlier filing gives room to correct errors, resolve questions with the region, and avoid a jobsite delay. Treat the minimum as a floor, not a target.⁸

3. Track the 180-day clock per calendar year

Keep a running tally of days worked in NRC jurisdiction. As a program approaches the limit, evaluate whether a specific NRC license is warranted rather than risking an overrun.¹

4. Amend before the scope changes, not after

New site, new radionuclide, new activity → amended Form 241 first. Retroactive amendments do not cure work performed outside the filed scope.¹³

5. Keep the home office as the true center of the license

Ensure the office that directs the work and holds the radiation safety records matches what the license and the 150.20 basis assume. This is both a legal predicate and an inspection reality.¹

Common pitfalls to avoid

• Filing NRC Form 241 to work in another Agreement State. Form 241 is for NRC jurisdiction; Agreement State destinations use their own process.¹³
• Assuming a home-state license authorizes work anywhere. It authorizes work in the issuing jurisdiction; elsewhere needs reciprocity or a separate license.²
• Overrunning 180 days. The annual cap is a hard planning constraint for NRC-jurisdiction work.¹
• Working outside the filed scope. A new site or source needs an amended filing first.¹
• Trying to distribute or leave material under reciprocity. The general license is for temporary conduct of your own licensed activity, not transfer or distribution.¹
• Ignoring transport and possession limits. Sources you travel with are still bound by your license limits and DOT transport rules.

Regulatory Considerations

Reciprocity sits at the intersection of the NRC's authority in non-Agreement areas and the Agreement States' authority under Section 274 of the Atomic Energy Act. The framework is federal in structure but implemented by whichever authority regulates the destination.

Key references:

• 10 CFR 150.20 — Recognition of Agreement State licenses. The rule that grants the general license, sets the filing requirement, and imposes the 180-day limit and conditions.¹
• 10 CFR Part 150 — Exemptions and continued regulatory authority in Agreement States and in offshore waters under Section 274, the broader part in which 150.20 sits.²
• NRC Form 241 — the report an Agreement State licensee files to invoke reciprocity in NRC jurisdiction.³
• 10 CFR 170.31 — the fee schedule, including Fee Category 16 for reciprocity filings.⁵
• NRC NUREG-1556, Volume 19 — program-specific guidance addressing reciprocity, and the vehicle for implementation-guidance updates flowing from the 2025 modernization effort.⁶
• Underlying protection and use rules — the work itself remains governed by 10 CFR Part 20 (protection standards) and, for medical use, 10 CFR Part 35, as adopted by the applicable authority.¹⁰¹¹

Agreement States administer their own reciprocity programs, so the destination state's rules control when the work is in an Agreement State. Of the jurisdictions DRPS serves, Florida, Maryland, Virginia, California, Nevada, Pennsylvania, New York, and New Jersey are Agreement States, while Washington, DC and Delaware are direct-NRC. Because rules and timelines shift—as the 2025 changes show—verify the current requirement with the authority having jurisdiction before each engagement. For state-specific context, see Florida radiation safety requirements, and for security obligations that travel with certain sources, see radioactive source security under Part 37. DRPS provides radioactive material license support and medical physicist consulting to keep multi-state programs compliant.

Frequently Asked Questions (FAQs)

What is NRC reciprocity?

Reciprocity is a mechanism that lets a specific licensee from one jurisdiction temporarily conduct its licensed activity in another jurisdiction without obtaining a second full license. Under 10 CFR 150.20, an Agreement State licensee is granted a general license to work in areas of NRC jurisdiction—non-Agreement States, areas of exclusive federal jurisdiction, and offshore waters—provided it files NRC Form 241, pays the required fee, and observes the conditions and limits in the rule.

When do I file NRC Form 241 versus an Agreement State reciprocity form?

You file NRC Form 241 to work in areas of NRC jurisdiction, which include non-Agreement States, federal facilities and other areas of exclusive federal jurisdiction, and offshore waters. To work in a different Agreement State, you do not use NRC Form 241; you use that destination state's own reciprocity process. The authority that regulates the place where the work happens is the authority you file with.

How long can I work under NRC reciprocity in a calendar year?

Activities conducted in NRC jurisdiction under the 10 CFR 150.20 general license, other than in offshore waters, are limited to 180 days in any calendar year. Work beyond that limit generally requires an NRC specific license rather than continued reliance on reciprocity.

What must I submit to file for NRC reciprocity?

You submit a completed NRC Form 241, a copy of your Agreement State specific license, and the fee specified in Fee Category 16 of 10 CFR 170.31, sent to the NRC Regional Administrator for the region in which the Agreement State that issued your license is located. Changes to work locations, materials, or activities require an amended Form 241.

Does reciprocity cover installing or servicing equipment and leaving sources behind?

No. The general license authorizes conducting the same licensed activity your home-state license permits, on a temporary basis; it is not a way to distribute, transfer, or permanently place radioactive material in the new jurisdiction, and it does not extend authority beyond what your specific license allows. Certain activities and license types have additional conditions, so the scope of the underlying license and the rule's conditions both govern what you may do.

Did the NRC change the reciprocity filing timeline in 2025?

Yes. Historically the initial NRC Form 241 had to be filed at least three days before beginning work. In 2025, under Executive Order 14300, the NRC moved to reduce that lead time so an initial Form 241 could be filed as late as the day work begins, and it issued interim staff guidance while a broader modernization of its byproduct-material rules proceeds. Because implementation is still settling, confirm the current filing deadline with the appropriate NRC regional office before you travel.

Is a home-state Agreement State license enough to work anywhere?

No. A specific license issued by one Agreement State authorizes activity within that state. Doing the same work elsewhere requires either reciprocity recognition by the authority that regulates the destination, or a separate specific license issued by that authority. Multi-state programs must map each work location to the correct regulator and file accordingly before starting work.

Key Takeaways

• Reciprocity travels your existing authorization; it does not expand it. Under 10 CFR 150.20 you may do the same activity your specific license permits, temporarily, in the new jurisdiction.¹
• File with the authority that regulates the destination. NRC Form 241 for NRC jurisdiction (including DC and Delaware among DRPS's states); the destination state's own process for another Agreement State.¹³
• Know the package and the fee. Form 241, a copy of your specific license, and the Fee Category 16 fee, to the Regional Administrator for your license's region.³⁵
• Respect the 180-day annual limit. Sustained NRC-jurisdiction work points toward a specific license, not stretched reciprocity.¹
• The 2025 changes cut the lead time, not the rigor. Same-day initial filing may now be allowed, but confirm the current requirement with the region and file accurately.⁸⁹
• Multi-state programs live or die on mapping. Every jobsite must be matched to its regulator, with filings current and amendments timely.³⁴

Conclusion

Reciprocity is what makes multi-state radioactive-material work practical, but it rewards precision. The mechanism is straightforward—a general license under 10 CFR 150.20, invoked by NRC Form 241 for work in NRC jurisdiction—yet the failure modes are equally straightforward: filing with the wrong authority, assuming a home-state license reaches everywhere, overrunning 180 days, or working outside a filed scope. A program that maps each destination to its regulator, files completely and on time, tracks its days and its amendments, and keeps the home office as the true center of the license can move across state lines confidently. And because the rules are actively changing—as the 2025 modernization of the filing timeline shows—the enduring habit is to verify the current requirement with the authority having jurisdiction before every engagement.

How DRPS Can Help

Diagnostic Radiation Physics Services works across a ten-state footprint and manages reciprocity as part of routine operations. DRPS helps facilities and traveling programs with radioactive material license support—including reciprocity filings, amendments, and mapping work locations to the correct regulator—together with radiation safety officer and medical physicist consulting support, delivered by board-certified medical physicists.

DRPS supports facilities across our service locations, including Florida, Maryland, Virginia, Washington DC, California, Nevada, New York, Pennsylvania, New Jersey, and Delaware. When licensed work crosses a state line, the goal is simple: be authorized before the work starts, and be able to prove it.

Related Resources

• NRC materials license guide
• The Radiation Safety Officer role
• Preparing for an NRC inspection
• Transport of radioactive material under DOT 49 CFR
• Radioactive source security under Part 37
• Radioactive material license support
• Radiation Safety Officer consulting

References

1. U.S. Nuclear Regulatory Commission. 10 CFR 150.20: Recognition of Agreement State licenses. nrc.gov
2. U.S. Nuclear Regulatory Commission. 10 CFR Part 150: Exemptions and Continued Regulatory Authority in Agreement States and in Offshore Waters Under Section 274. nrc.gov
3. U.S. Nuclear Regulatory Commission. NRC Form 241: Report of Proposed Activities in Non-Agreement States, Areas of Exclusive Federal Jurisdiction, or Offshore Waters. nrc.gov
4. U.S. Nuclear Regulatory Commission. Frequently Asked Questions About NRC Reciprocity. nrc.gov
5. U.S. Nuclear Regulatory Commission. 10 CFR 170.31: Schedule of fees for materials licenses and other regulatory services (Fee Category 16, reciprocity). nrc.gov
6. U.S. Nuclear Regulatory Commission. NUREG-1556, Volume 19: Consolidated Guidance About Materials Licenses — Guidance About Agreement State Programs and Reciprocity. nrc.gov
7. U.S. Nuclear Regulatory Commission. Agreement State Program (Section 274, Atomic Energy Act of 1954, as amended). nrc.gov
8. The White House. Executive Order 14300: Ordering the Reform of the Nuclear Regulatory Commission. May 23, 2025. federalregister.gov
9. U.S. Nuclear Regulatory Commission. Modernizing NRC Regulations for Byproduct Material Use (rulemaking implementing reciprocity changes). Federal Register. 2026. federalregister.gov
10. U.S. Nuclear Regulatory Commission. 10 CFR Part 20: Standards for Protection Against Radiation. nrc.gov
11. U.S. Nuclear Regulatory Commission. 10 CFR Part 35: Medical Use of Byproduct Material. nrc.gov