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Category Archives: General

REFRESH: 2.802 vs. 2.206 — What’s the Difference?

George Deegan
Senior Program Analyst (Nuclear Materials/Waste Management)
 

refresh leafMathematically, of course, the answer is 0.596 – a tiny amount – but when referring to two different parts of NRC regulations, there’s a big difference. 10 CFR Part 2.802 and 10 CFR Part 2.206 both describe petition processes. However, 2.802 petitions are requests from the public for a new rule (regulation) while 2.206 petitions are related to enforcement actions.

My area, the Office of Federal and State Materials and Environmental Management Programs (FSME), usually gets two to four 2.802 rulemaking petitions a year about medical or general license issues. However, petitions are also addressed in other offices, including the Office of Nuclear Reactor Regulation. The basic steps for submitting petitions for rulemaking to the NRC are found in 10 CFR 2.802, with specific details on what to include in the petition documented in paragraph (c).

For information on the process for submitting a petition for rulemaking to the NRC, please visit this page, which also has a link to the NRC’s petition for rulemaking dockets.

The 2.206 process allows anyone to ask the NRC to take enforcement action against NRC licensees. Depending on the results of its evaluation, NRC could modify, suspend, or revoke an NRC-issued license or take other enforcement action to fix a problem. Additional information on how to submit a petition under 10 CFR 2.206, how the agency processes the request, and status information on 2.206 petitions we’ve received can be found at here.

There have been occasions where a petitioner has invoked the term “2.206” when the request was really a petition for rulemaking under 2.802. Unfortunately, this situation often delays the petition while staff members review the request and get it put into the right process.

The NRC’s petition process provides the public with a voice in how we regulate our licensees. Hopefully, this post clarifies which process is appropriate for a given situation and highlights the difference between the two numbers beyond 0.596!

“Refresh” is a new initiative where we revisit some earlier posts. This originally ran in June 2011.

Throwback Thursday — Atoms for Peace

hpAtoms for Peace BusWhich U.S. president launched this program – Atoms for Peace? The program’s intent was to share nuclear technology and isotopes with American allies while maintaining control of weapons-grade material. It also supplied equipment and information to schools, hospitals and research institutions within the U.S. (Photo by Ed Westcott/DOE)

 

NRC Science 101: The What and How of Geiger Counters

Joe DeCicco
Senior Health Physicist
Source Management and Protection Branch
 

In earlier Science 101 posts, we talked about ionizing radiation and different types of radiation. In this post, we’ll look at the Geiger counter, an instrument that can detect radiation.

science_101_squeakychalkJust to recap, the core of an atom (the nucleus) is surrounded by orbiting electrons, like planets around a sun. The electrons have a negative charge and usually cancel out an equal number of positively charged protons in the nucleus. But if an electron absorbs energy from radiation, it can be pushed out of its orbit. This action is called “ionization” and creates an “ion pair”—a free, negatively charged electron and a positively charged atom.

Humans cannot detect creation of an ion pair through their five senses. But the Geiger counter is an instrument sensitive enough to detect ionization. Most of us have heard or seen a Geiger counter. They are the least expensive electronic device that can tell you there is radiation around you—though it can’t tell you the original source of the radiation, what type it is or how much energy it has.

How does it work? A Geiger counter has two main parts—a sealed tube, or chamber, filled with gas, and an information display. Radiation enters the tube and when it collides with the gas, it pushes an electron away from the gas atom and creates an ion pair. A wire in the middle of the tube attracts electrons, creating other ion pairs and sending a current through the wire. The current goes to the information display and moves a needle across a scale or makes a number display on a screen. These devices usually provide “counts per minute,” or the number of ion pairs created every 60 seconds. If the loud speaker is on, it clicks every time an ion pair is created. The number of clicks indicates how much radiation is entering the Geiger counter chamber.

You hear a clicking sound as soon as you turn on the speaker because there is always some radiation in the background. This radiation comes from the sun, natural uranium in the soil, radon, certain types of rock such as granite, plants and food, even other people and animals.

The background counts per minute will vary; the needle will move or the number will change even when there is no know radiation source nearby. Many different things cause this fluctuation, including wind, soil moisture, precipitation (rain or snow), temperature, atmospheric conditions, altitude and indoor ventilation. Other factors in readings include geographical location (higher elevations give higher counts), the size and shape of the detector, and how the detector is built (different chamber material and different gases).

geigercounterDepending on the elevation and the type of Geiger counter, a typical natural background radiation level is anywhere from five to 60 counts per minute or more. Because background radiation rates vary randomly, you might see that range standing in one spot. It is important to understand that the Geiger counter indicates when an ion pair is created, but nothing about the type of radiation or its energy.

Other types of instruments can provide an exposure rate (expressed as milliroentgen per hour or mR/hr). These counters must be calibrated to read a particular type of radiation (alpha, beta, gamma, neutron, x-ray) as well as the amount of energy emitted. The reading will only be accurate for that type of radiation and that energy level. And these instruments need to be calibrated regularly to be sure they are providing correct information over time.

For more sophisticated environmental radiation readings, check out the Environmental Protection Agency’s nationwide system, RadNet. Using equipment far more sensitive than a Geiger counter, it continuously monitors the air and regularly samples precipitation, drinking water and pasteurized milk.

Over its 40-year history, RadNet has developed an extensive nationwide “baseline” of normal background levels. By comparing this baseline to measurements across the U.S. states in March 2011, following the accident at the Fukushima reactors in Japan, the EPA was able to detect very small radiation increases in several western states. EPA detected radiation from Japan that was 100,000 times lower than natural background radiation—far below any level that would be of concern. And well below anything that would be evident using a simple Geiger counter, or even Geiger counters spread across the country.

If RadNet were to detect a meaningful increase in radiation above the baseline, EPA would investigate immediately. With its nationwide system of monitors and sophisticated analytical capability, RadNet is the definitive source for accurate information on radiation levels in the environment in the U.S.

By the way, the Geiger counter is also called a Geiger-Mueller tube, or a G-M counter. It was named after Hans Geiger, a German scientist, who worked on detecting radiation in the early 1900s. Walter Mueller, a graduate PhD student of Geiger’s, perfected the gas-sealed detector in the late 1920s and received credit for his work when he gave his name to the Geiger-Mueller tube.

Throwback Thursday — Kennedy’s Nuclear Visit

hpDr_Alvin_Sen_KennedyBefore John F. Kennedy became president, he was elected to the U.S. House of Representatives and the U.S. Senate. During his time on Capitol Hill, he visited the Oak Ridge National Laboratory in Tennessee. Here, he’s photographed with ORNL Director Alvin Weinberg. Can you guess the year this photo was taken and who accompanied the then-Senator Kennedy? Extra points if you know what nuclear technology Weinberg is credited with spearheading. (Photo taken by Ed Westcott/DOE)

 

The NRC Makes a Determination After Last Year’s Crane Collapse

Victor Dricks
Senior Public Affairs Officer
Region IV

 

Last year, the Arkansas Nuclear One facility experienced a tragic incident when a crane collapsed. One person was killed, eight were injured and important plant equipment was damaged. The NRC has now issued two “yellow” inspection findings as a result. The “yellow” means we found substantial safety significance related to the incident.

arkansasWorkers were moving a massive component out of the plant’s turbine building when the incident occurred. Unit 1 was in a refueling outage at the time, with all of the fuel still in the reactor vessel. At the time, Entergy Operations declared a Notice of Unusual Event, the lowest of four emergency classifications used by the NRC, because the crane collapse caused a small explosion inside electrical cabinets. The damaged equipment caused a loss of off-site power. The NRC’s senior resident inspector had driven to the plant to personally survey the damage and monitor the licensee’s response from the plant’s control room.

Here’s why NRC decided the incident had substantial safety significance even though both plants were safely shut down and there was no radiological release or danger to the public: Emergency diesel generators were relied upon for six days to supply power to heat removal systems.

The falling turbine component damaged electrical cables needed to route power from an alternate AC power source to key plant systems at both units. This condition increased risk to the plant because alternate means of providing electrical power to key safety-related systems was not available using installed plant equipment in the event the diesels failed.

Unit 2, which was operating at full power, automatically shut down when a reactor coolant pump tripped due to vibrations caused when the heavy component fell and hit the turbine building floor. Unit 2 never completely lost offsite power, and there was a way to provide it with emergency power using the diesel generators.

The NRC conducted an Augmented Team Inspection. We prepared a detailed chronology of the event, evaluated the licensee actions in response, and assessed what may have contributed to the incident. (Worker safety issues are the responsibility of the Occupational Safety and Health Administration, which conducted an independent inspection of the incident.)

The NRC determined that the lifting assembly collapse was a result of the licensee’s failure to adequately review the assembly design and to do an appropriate load test.

We held a public meeting in Russellville, Ark., on May 9, 2013, to discuss the team’s initial findings. From its follow-up inspections, the NRC issued a preliminary red finding to Unit 1 and a preliminary yellow finding to Unit 2. These are documented in a March 24 inspection report.

NRC held a regulatory conference with Entergy officials on May 1, and after considering information provided by the licensee determined that “yellow” findings were appropriate to characterize the risk significance of the event for both Unit 1 and 2. The NRC will determine the right level of agency oversight for the facility and notify Entergy officials of the decision in a separate letter.

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