Nuclear Engineering Regulatory Guidelines

🔬 Radiation Protection in PET/CT: Is Wearing a Lead Apron Effective? 🤔 In the field of Nuclear Medicine, particularly in PET/CT imaging, radiation safety is a critical concern. A common question among healthcare professionals is: “Should I wear a lead apron in a PET/CT unit?” Let’s explore the physics behind this question and why lead aprons are not effective in PET/CT environments. 1️⃣ Understanding the Radiation in PET/CT 📸 CT Scanner: • Produces x-rays with energies between 80-140 keV. • Lead aprons are highly effective here due to the photoelectric effect, where low- to medium-energy photons are absorbed by lead (high atomic number Z = 82). ⚛️ PET Scanner: • Uses positron-emitting radionuclides like fluorine-18 (18F). • When a positron meets an electron, they undergo annihilation, releasing two 511 keV gamma photons traveling in opposite directions. • 511 keV gamma rays are highly penetrating and interact mainly through Compton scattering, reducing lead’s protective capability. 2️⃣ Why Lead Aprons Don’t Work in PET/CT ➡️ Energy Mismatch: Lead aprons are designed for low- to mid-energy x-rays (<150 keV). At 511 keV, lead’s attenuation efficiency drops significantly. ➡️ Limited Attenuation: A standard 0.5 mm lead apron attenuates only 1-3% of 511 keV photons due to the dominance of Compton scattering, making them virtually useless. ➡️ Exposure Source: Most radiation exposure in PET/CT comes from the radioactive patient, not the scanner. Wearing a lead apron offers minimal protection from this type of radiation. 3️⃣ How to Stay Protected in PET/CT? ✅ Radiation safety in PET/CT relies on the core principles of time, distance, and shielding: 🕒 Time: Minimize time spent near the radioactive patient after tracer injection. 📏 Distance: Follow the inverse square law: Doubling the distance from the patient reduces radiation intensity by 75%! 🛡️ Shielding: Use: • Fixed barriers (leaded glass, shielded walls). • Mobile shields designed for high-energy gamma radiation. 🔔 Takeaway: Wearing a lead apron in a PET/CT unit is scientifically ineffective due to the nature of high-energy gamma radiation emitted by PET tracers. Instead, focus on radiation protection protocols designed for high-energy environments: Time, Distance, and Proper Shielding. Let’s keep advancing our knowledge of radiation safety in medical imaging! 💡 What’s your experience with radiation protection in PET/CT? Share your thoughts! 👇 #NuclearMedicine #RadiationProtection #PETCT #MedicalPhysics #RadiologySafety #MedicalImaging

Battery Energy Storage Doesn’t Last Forever What happens after 10–15 years of operation? Even during permitting, regulators want to know your decommissioning plan. Here’s why: Safety risks are real (high voltage, fire hazards, toxic materials). A 120 MW site could cost over $6M to fully decommission. Here’s how to prepare - and how to do it right. Top 5 Steps to Decommissioning a BESS: De-energize – Safely disconnect power & isolate battery modules Disconnect – Remove cables, switchgear & enclosures Remove – Lift, transport & handle heavy equipment Dispose – Reuse, recycle, or properly discard materials Restore – Clear the site & return to original condition Takeaway: If you’re building BESS, plan its end now.

Last month many of you told me that our low-dose radiation models feel overdue for an update. Now the federal government has added its own push. On May 23, four Executive Orders instructed relevant agencies to modernize licensing, adopt science-based radiation limits, and undertake a full review of NRC regulations, including ALARA guidance, during oversight and rulemaking. The American Nuclear Society quickly assembled an expert group to map the Orders against existing science and policy. Their memo concludes: • Adopting science-based dose limits is the right goal. • Reopening the 70-year debate over the Linear No-Threshold (LNT) model would drain limited NRC resources without producing a better quantitative model. • The practical win lies in using ALARA as it was meant to be used: an optimization that balances marginal dose reduction with economic and societal benefit. Today it too often becomes automatic dose minimization, which can do more harm than good. So where might regulators and licensees start to make this vision practical? Here are some ideas: – Require cost–benefit analysis in licensee ALARA plans, using established guidance like NUREG-1530, so reviewers can quickly judge whether further dose reductions are warranted. – Strengthen inspector training to distinguish true optimization from reflexive minimization, especially when dealing with exposures near background. – Create a centralized library of ALARA case studies, aggregating existing DOE and NRC examples to give licensees real-world precedents for risk-informed decisions. – Coordinate NRC, DOE, and state regulators through a joint framework aligned with ICRP-103, so low-level radiation work is governed by consistent expectations across jurisdictions. The ANS memo offers a strong foundation: https://lnkd.in/efzzgVyW What’s your stance? Where do you see the biggest opportunity to make ALARA more reasonable in day-to-day practice? Feel free to share your experience. #RadiationProtection #HealthPhysics #ALARA #NuclearSafety #RegulatoryReform

The American Bureau of Shipping (ABS) is laying the technical and regulatory frameworks necessary for the maritime industry to safely and efficiently adopt nuclear clean technologies. ABS has recently released the Requirements for Nuclear Power Systems for Marine and Offshore Applications (https://lnkd.in/gWs7TdmP), the first comprehensive guidelines specifically designed for nuclear-powered vessels and floating power platforms. These guidelines outline essential safety, operational, and regulatory considerations and include a stakeholder interface document that defines the roles of classification societies, nuclear regulators, flag administrations, and port authorities. While nuclear marine systems are not a new concept, there has been a lack of standardized guidelines until now. Floating nuclear power plants present a practical starting point. The U.S. successfully operated one in Panama in the 1960s, and Russia's Akademik Lomonosov has demonstrated the viability of this concept today. These compact and cost-effective floating reactors can meet offshore energy demands while avoiding the challenges associated with land-based installations. In terms of ships, existing nuclear-powered vessels like Sevmorput, the iconic Russian icebreaker Arktika, and the new Yakutia class showcase the maturity and reliability of nuclear technology for safe civil maritime operations in the Arctic, where oil-powered vessels cannot operate with the required reliability. ABS is also actively collaborating with leading organizations, including the U.S. Department of Energy (DOE), KRISO(Korea Research Institute of Ships & Ocean Engineering), HD Korea Shipbuilding & Offshore Engineering Co., Ltd. (HD KSOE), and KEPCO E&C. Collaborations with the LISCR | The Liberian Registry and Herbert Engineering Corp. (HEC) have resulted in pioneering studies such as modeling MSR integration on LNG carriers.   These studies highlight the potential for decades-long operational lifespans without refueling, increased cargo capacity, and emissions-free operations. Nuclear marine power is not only more environmentally friendly but also faster, more efficient, and more economical through its operational lifespan compared to any other solution. The advantages of nuclear propulsion extend beyond these benefits. Explore all the advantages compared to conventional vessels here: https://lnkd.in/g6Yv4hvT.

The Rule of Threes (in survival): Shelter — Three hours Water — Three days Food — Three weeks In other words, you should assume you can survive without shelter for three hours, without water for three days, and without food for three weeks. In an urban environment, the Rule of Threes still applies. The solutions are just easier to find, probably as close as your nearest Costco. At the very least, go out and purchase the following: Emergency blankets and sleeping bags. Make sure they’re rated for the lowest recorded temperature in your area. In a home robbed of power, “shelter” equals warmth. If you have a chimney, get seasoned wood; if not, get a vent-free gas stove. Don’t forget the fuel. Two weeks’ worth of water. Budget at least one gallon per person per day, and backup water purification tablets are a good idea. If you live close to the ocean, you could also buy a desalinator for turning salt water into potable water. Two weeks’ worth of food with a long shelf life. Lentils, rice, beans, canned vegetables, etc. Protein bars are a good supplement and provide some variety, as do military MREs. Emergency lighting, including a few headlamps, and a ton of batteries. First-aid kit and (for the ambitious) extra antibiotics. Ciprofloxacin (Cipro) and Azithromycin (Z-Paks), while imperfect, are good broad-spectrum antibiotics. This basic prep might seem crazy if you’ve never been caught in a disaster. No one in SF expected the 1989 Loma Prieta earthquake, either, but it left thousands without running water for 10 days, and without power for four days.

The economics of new nuclear plants are heavily influenced by their capital cost, which accounts for at least 60% of their LCOE. With large upfront capital costs, the longer it takes to license and build a reactor the higher the cost of capital--because you're paying interest on loans for a long time before you get to operations. Anything that can reduce the amount of upfront capital needed on a project and shorten the duration of licensing reviews and construction--to accelerate time to operations and generating $$$--is critical to bringing down the cost of a project. A lot of the new nuclear technologies focus on reducing costs, such as with simpler designs, modular construction, standardization, etc. But what about other drivers in the timeline--like licensing reviews? I've spent a lot of time over the years thinking of ways to streamline U.S. Nuclear Regulatory Commission licensing reviews, and write/speak about this topic often. This includes improving #NEPA/environmental reviews. I've done this for 20 years, and have seen both ends of the spectrum--some good examples (like the Kairos Power application review) and some not so good. Since there's a renewed interest in improving NRC envirornmental reviews, I'm posting a paper I published back in 2019 --"Streamlining NRC NEPA Reviews for Advanced Reactor Demonstration Projects." This report identifies some of the challenges that have been apparent in NEPA reviews of commercial nuclear energy projects, and makes several policy and operational recommendations to support more efficient review for first-of-a-kind nuclear projects while still protecting the environment. https://lnkd.in/eQqtUK8N

Radiological Protection Principles ☢️💥 . . . . • Justification: No practice or source within a practice should be authorized unless the practice produces sufficient benefit to the exposed individuals or to society to offset the radiation harm that it might cause; that is: unless the practice is justified, taking into account social, economic and other relevant factors • Optimisation(ALARA): All living things are exposed to ionising radiation from the natural (called background radiation) and man-made radiation sources. Ionising radiation may cause biological changes in the exposed person hence the doses to the occupational workers shall be kept As Low As Reasonably Achievable (ALARA) and doses to patients shall be optimized. Suitable control measures shall be employed to minimise radiation exposure so that maximum benefits are derived with minimum radiological risk. • Dose Limitations (Never exceed Dose Limits): The normal exposure of individuals resulting from all relevant practices should be subject to dose limits to ensure that no individual is exposed to a risk that is judged to be unacceptable. ___________Dose Limitations ☢️____________ Part of the body 🧠🫀🫁☢️⚕️ ______________________ Occupational Exposure Public Exposure • Whole body ☢️ (Effective dose) 20 mSv/year averaged over 5 consecutive years; 30 mSv in any single year 1 mSv/y • Lens of eyes ☢️ (Equivalent dose) 150 mSv in a year 15 mSv/y • Skin (Equivalent dose) 500 mSv in a year 50 mSv/y Extremities • (Hands and Feet)☢️ Equivalent dose 500 mSv in a year - For pregnant radiation workers, after declaration of pregnancy 1 mSv on the embryo/fetus should not exceed. Where, Occupational Exposure - Radiation Exposure to worker involved in a practice in which he/she is exposed due to handling of radioactive source or radiation generating equipment. Public Exposure - Radiation Exposure to public due to above practices.

India’s Nuclear Power Plants: Among the Safest Globally, Union Minister Dr. Jitendra Singh assures Rajya Sabha Union Minister Dr. Jitendra Singh has reaffirmed India’s position as a global leader in nuclear safety. Addressing the Rajya Sabha, he emphasized that India’s nuclear power plants follow a stringent “safety first, production next” policy, aligning with international benchmarks and standards Dr. Singh outlined a comprehensive safety framework for nuclear facilities: • Inspections: Quarterly checks during construction, biannual reviews for operational plants, and mandatory five-year license renewals ensure ongoing compliance. • Radiation Emission Control: Indian plants operate significantly below the global safety benchmark of 1,000 microsieverts. For instance, Kudankulam’s radiation levels have plummeted to 0.002 microsieverts, reflecting a decade of steady improvement. • Disaster Resilience: Plants are strategically designed to withstand extreme natural events, with locations far from tsunami-prone zones and elevations exceeding historical flood levels. Global Oversight and Recognition India’s nuclear safety standards are validated by periodic reviews from international organizations like the World Association of Nuclear Operators (WANO). This global recognition underscores the country’s leadership in nuclear technology. Milestones in Nuclear Excellence India’s achievements showcase its technological and operational capabilities: • Kaiga Generating Station: Set a world record with 962 days of continuous operation. • Tarapur Plant: Completed 50 years of uninterrupted service, a rarity in global nuclear history. • Kakrapar PHWR: India’s first indigenously developed Pressurized Heavy Water Reactor is now operational, signifying self-reliance in advanced nuclear technology. • Kudankulam Plant: Overcame decades of delays to become fully functional. Beyond Energy Generation India’s nuclear program aligns with Homi Bhabha’s vision of peaceful atomic energy applications: • Agriculture: Development of radiation-resistant crop varieties. • Food Preservation: Use of radiation to extend the shelf life of perishables. • Healthcare: Production of medical isotopes for advanced cancer treatments. • Security: Development of protective gear for law enforcement. Policy Framework for Investment Dr. Singh addressed concerns about the Civil Liability for Nuclear Damage Act, 2010, which balances public safety with investment viability. The act ensures operator accountability while allowing supplier responsibility under specific conditions, fostering foreign and domestic collaboration. India’s Role on the Global Stage Once a minor player, India now sets global standards in nuclear energy. Dr. Singh emphasized that the country’s achievements in safety and sustainability contribute to its leadership in climate action and energy innovation. MOJAHIDA MUSROOR Indian Youth Nuclear Society IYNS

“Knowledge isn’t power; applied knowledge is power.” Let’s take a deeper look at how risks are managed at U.S. #nuclear power plants. It all begins with safety assessments and a regulatory framework, particularly in relation to the U.S. Nuclear Regulatory Commission (NRC) and state regulators which includes the following elements: 1. NRC Oversight: The NRC is responsible and is held accountable for ensuring the safety and security of nuclear power plants in the U.S. 2. Probabilistic Risk Assessment (#PRA): As part of its risk informed safety framework, the NRC employs PRAs to evaluate the likelihood of potential accidents and their consequences. Plants are assessed based on various scenarios, including #seismic events, equipment failures, and human errors. As an example, plants located in seismically active regions, like Diablo Canyon Nuclear Power plant, undergo rigorous seismic evaluations CONTINUOUSLY. Estimating the probability of a major seismic event causing a partial meltdown at a nuclear power plant involves highly complex (PRAs) and an understanding of both seismic hazards and the plant's vulnerabilities. While the probability of a seismic event occurring can be quantified, estimating the likelihood of that event leading to a partial meltdown involves much more analysis. This includes evaluating the plant's response to ground shaking, the likelihood of equipment failures, and the effectiveness of safety system. 3. Regulatory Assessments: The NRC and other regulatory bodies require nuclear plants to conduct regular seismic risk assessments and update their safety measures based on new data and research. These assessments help ensure that the plants can withstand severe seismic events and minimize the risk of accidents. While precise numerical probabilities can vary, the probability of these events leading to severe outcomes like a partial meltdown with a release of radioactive materials to the public is lower than most risks humans choose to take every day, like driving a car. And the probability of radioactive materials being released from the plant if a melt down was to occur, is even a lower probability because of the over engineering at the site. “Defense in depth” is a central tenant for all nuclear plants in the U.S. While some plants may face more significant risks than others, the focus remains on continuous improvement, learning from past incidents, and adapting to new information and technologies as they become available. The North Anna plant in Virginia experienced the most severe earthquake in their recorded history. North Anna was able to withstand a beyond-design-basis earthquake without safety being compromised. Its worked as it was designed. The goal of seismic design today is to choose a safe shutdown so that the probability that it will be exceeded over the facility lifetime is very low—and if a larger earthquake does occur, there is sufficient safety margin to prevent a disaster from occurring.

How Banks Ensure Regulatory Compliance: Conducting Treasury Activities Regulatory compliance is a cornerstone of modern banking, ensuring financial institutions operate within legal frameworks. For banks, particularly in treasury activities, maintaining compliance is crucial to uphold trust, manage risk, and avoid significant penalties. Here is how banks ensure regulatory compliance in their treasury operations: Understanding Regulatory Requirements: Banks must have a comprehensive understanding of relevant regulations, including international directives and national rules. These cover capital adequacy, liquidity management, and risk assessment. Robust Internal Controls: Implementing robust internal controls is essential. Compliance departments monitor and enforce adherence to regulatory standards through regular audits and reviews of treasury activities. Effective Risk Management: Banks use risk management frameworks to identify, assess, and mitigate risks in their treasury operations. This includes market risk, credit risk, and operational risk, maintaining a conservative approach. Training and Education: Continuous training ensures staff are aware of regulatory changes and understand their roles in compliance. Specialised training for treasury staff focuses on specific compliance requirements. Technology and Automation: Advanced software solutions monitor transactions, manage data, and generate compliance reports. These tools detect potential compliance issues in real-time for prompt corrective actions. Regular Reporting and Documentation: Accurate and timely reporting to regulatory bodies is essential. Comprehensive documentation of all treasury activities ensures transparency and provides a clear audit trail. Engagement with Regulators: Proactive engagement with regulators keeps banks informed about upcoming regulatory changes and provides guidance on compliance matters, addressing issues before they escalate. Scenario Analysis and Stress Testing: Conducting scenario analysis and stress testing helps ensure compliance under various market conditions. Banks assess the impact on their treasury activities to ensure they can withstand adverse conditions. Ensuring regulatory compliance in treasury activities is a multi-faceted process requiring understanding regulations, implementing robust controls, managing risks, continuous education, leveraging technology, accurate reporting, engaging with regulators, and conducting scenario analysis. By prioritising compliance, banks navigate the complexities of the regulatory landscape, contributing to the stability and integrity of the financial system.