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Category Archives: Nuclear Materials

Do Not Fear Your Smoke Detector – It Could Save Your Life

Maureen Conley
Public Affairs Officer
 

smokedetectornewWe sometimes get calls from people worried about radiation from smoke detectors in their homes. There are many reasons why the public need not fear these products.

Ionization chamber smoke detectors contain very small amounts of nuclear material. They might use americium-241, radium-226 or nickel-63. These products detect fires early and can save lives. [We explained how smoke detectors work in greater detail in an earlier blog post.]

The Atomic Energy Commission granted the first license to distribute smoke detectors in 1963. These early models were used mainly in factories, public buildings and warehouses. In 1969, the AEC allowed homeowners to use smoke detectors without the need for a license. Their use in homes expanded in the early 1970s. The NRC took over from the AEC in 1975.

Makers and distributors of smoke detectors must get a license from the NRC. They must show that the smoke detector meets our health, safety and labeling requirements.

Most smoke detectors sold today use 1 microcurie or less of Am-241. They are very safe. A 2001 study found people living in a home with two of these units receive less than 0.002 millirems of radiation dose each year. That is about the dose from space and the earth that an East Coast resident receives in 12 hours. Denver residents receive that dose in about three hours. These doses are part of what is known as “background radiation.”

The radioactive source in the smoke detector is between two layers of metal and sealed inside the ionization chamber. The seal can only be broken by the deliberate use of force, which obviously we discourage. Still, even then it would result in only a small radiation dose. The foil does not break down over time. In a fire, the source would release less than 0.1 percent of its radioactivity. It’s important to understand that none of the sources used in smoke detectors can make anything else radioactive.

What about disposing of smoke detectors? A 1979 analysis looked at the annual dose from normal use and disposal of Am-241 smoke detectors. The study used actual data and assumptions that would overstate the risk. It allowed the NRC to conclude that 10 million unwanted smoke detectors each year can be safely put in the trash.

The 2001 study looked at doses from misuse. It found that a teacher who removed an americium source from a smoke detector and stored it in the classroom could receive 0.009 millirems per year. If the teacher used the source in classroom demonstrations, handling it for 10 hours each year would give less than a 0.001 mrem dose. A person who swallowed the source would receive a 600 mrem dose while it was passing through the body.

I hope this information allays concerns. Unless you remove and swallow the source, your dose from a smoke detector could not be distinguished from what you get throughout your day. And that smoke detector could save your life.

Updating Nuclear Materials Transportation Regulations

Jessica Umaña
Project Manager, Division of Spent Fuel Storage and Transportation
 

The idea of transporting nuclear materials can make people nervous. It’s easy to imagine worst-case accidents on the highway or involving a train. But stringent safety requirements, as well as coordination among federal agencies, international regulators, and state and local officials, help to ensure these shipments are made safely. This structure provides many layers of safety.

From time to time, the requirements are updated to address new information. The International Atomic Energy Agency (IAEA) and U.S. Department of Transportation recently updated their requirements. The NRC is now amending ours to reflect those updates, as well as to make some changes we feel are needed based on recent experience. You can read the Federal Register notice on the proposed rule.

mapWhile the rules are being updated, the fact remains that nuclear materials are transported safely all the time. By far the majority of shipments involve small quantities of nuclear materials. Millions of these shipments are made each year and arrive at their destination without incident. Occasionally, the carrier might be involved in a traffic accident. But in decades of transporting nuclear materials, there has never been an accident that resulted in a radioactive release.

Smaller shipments must be made in compliance with DOT regulations for shipping hazardous materials. The greater the potential risk of the contents, the more stringent DOT’s packaging requirements are. The DOT regulations limit how much radioactivity can be transported in each package. That way, no transport accident involving these small shipments would pose a serious health threat.

But what about larger amounts of radioactive materials? What about spent nuclear fuel?

In addition to having to meet DOT requirements, more radioactive cargo such as spent fuel must meet NRC regulations for nuclear materials packaging and transport in 10 CFR Part 71. These regulations include very detailed requirements for shipping under normal conditions, as well as stringent tests to show the packages can withstand severe accidents. These are the regulations we are updating now.

If you would like to learn more about the transportation of spent fuel and radioactive materials, see our newly updated backgrounder.

When Gauges Go Missing … UPDATED

Neil Sheehan
Public Affairs Officer, Region I
 

It’s easy to imagine the sense of distress that must have washed over a portable nuclear gauge user one recent morning when he realized the device he had stowed in the back of his truck was missing. The gauge had apparently tumbled from his vehicle as he drove along a road near Martinsburg, W.Va.

Despite the gauge user’s prompt retracing of his steps, the device was nowhere to be found and, as of today, has not yet been retrieved.

While the search goes on, some perspective is in order regarding the use of such gauges, which contain sealed sources of radioactive materials and are designed to take measurements of soil density at construction and other work sites. The reality is the loss of these portable gauges is an infrequent occurrence and that is due, in large part, to the requirements developed over time to avoid that from happening.

Indeed, NRC and Agreement State regulations clearly spell out the precautions gauge operators must take when the devices are not in use. (Agreement States are those that have signed an agreement with the NRC to regulate nuclear materials used within their borders for which the NRC would otherwise be responsible.)

For one thing, there is a security requirement that a minimum of two independent physical controls must be utilized to prevent unauthorized removal of a gauge when it is not under direct control and surveillance of company personnel. For another, there must be constant surveillance of a gauge when it is in an unrestricted area.

When violations of these requirements occur in non-Agreement States, the NRC will consider whether enforcement action is warranted. Agreement States will do the same in their jurisdictions.

What’s more, the NRC and Agreement States conduct typically unannounced periodic inspections of gauge owners to discern whether security and other requirements are being properly followed.

Provided the sealed source remains inside the shielded gauge, it should not pose a threat to the person or persons who have it in their possession. Nevertheless, the device needs to be back in the hands of personnel qualified to handle such material as soon as possible.

In a post-9/11 world, the NRC takes very seriously the security of radioactive materials, from nuclear fuel used in power reactors to small amounts of radioactive material housed in portable gauges transported on pick-up trucks.

05/17/2013 – Updated: There is now a happy post-script to the case of portable nuclear gauge that went missing earlier this month in West Virginia.

On May 3, a Pennsylvania firm doing work in the Mountain State reported to the NRC that a gauge had fallen off one of its trucks and could not be located. The NRC issued a press release on May 6 advising the public to be on the lookout for the device.  The Pennsylvania Department of Environmental Protection (DEP) put out its own release regarding the missing gauge on May 14, based on the fact that its owner, Valley Quarries, is headquartered in Chambersburg, Pa., and is licensed by the state.

A break occurred on May 15 when a Maryland resident contacted the DEP to say he had spotted the gauge along a roadside near Martinsburg, W.Va., and placed it in his trunk after deciding it must be something important. It apparently remained there until being handed over to the DEP and, in turn, to Valley Quarries.

The good news is that a preliminary evaluation has found the gauge was apparently not damaged. A service provider for Valley Quarries will confirm that is the case. n the meantime, the NRC’s inspection of the loss of the gauge is still in progress. As part of that review, the NRC and DEP teamed up for an inspection at the company’s headquarters late last week to evaluate safety and security protocols used by the firm with respect to its portable nuclear gauges.

When the NRC’s inspection is completed, the results will be made available to the public.

Working Together to Keep Radioactive Materials Safe

Kim Lukes
Health Physicist
Office of Federal and State Materials and Environmental Management Programs
 

Occasionally the Department of Energy makes news when it picks up radioactive materials from users who no longer want them. DOE plays an important role when it secures these sources pending final disposal — often prompting headlines about keeping “dirty bomb” materials away from bad guys.

These headlines overlook the many layers of protection that keep radioactive materials secure every day. The NRC and Agreement State co-regulators require licensees with materials that could pose the biggest hazard to store them securely. When no longer needed, they can be securely stored on site, safely moved to a commercial disposal site or turned over to the federal government for disposal. The NRC and Agreement State regulators inspect licensees periodically to make sure they are meeting the requirements. These requirements provide adequate protection against theft or misuse of radioactive materials in the U.S.

Earlier this month the National Nuclear Security Administration (NNSA), an arm of DOE, picked up a source that was no longer needed for medical research at Temple University in Pennsylvania. By law, DOE is responsible for disposing of this type of waste, although DOE does not yet have an approved disposal site or method. The department will store the source — in this case, an old irradiator containing cesium-137 — until a disposal site is available.

Before NNSA picked up the source, it was protected as all risk-significant radioactive sources are. (These materials are also known as International Atomic Energy Agency Category 1 and Category 2 quantity of sources). The NRC and its Agreement State partners put measures in place after Sept. 11, 2001, to protect high-risk radioactive materials against theft. Today, these measures protect more than 75,000 sources used in medical, commercial and research activities. The NRC just updated and expanded these security requirements, adding them to a new section of our regulations — 10 CFR Part 37.

The security requirements include:

• Background checks and fingerprinting to ensure that people with access to radioactive materials are trustworthy and reliable;

• Controls on who can access areas where radioactive materials are stored or used;

• Security plans and procedures to monitor, detect, assess and respond to unauthorized access attempts;

• Coordination and response planning between licensees and local law enforcement;

• Coordination and tracking of radioactive materials shipments; and

• Security barriers to discourage theft of portable devices.

Besides its Offsite Source Recovery Project, NNSA has a Global Threat Reduction Initiative to help improve the security of nuclear and radioactive materials internationally. NNSA also provides voluntary security enhancements domestically. Licensees who meet NRC or Agreement State security requirements can chose to work with NNSA to put additional security enhancements in place. The NRC cooperates with NNSA on this voluntary program. Security of these materials is a top priority for the NRC. We continue to assess and improve our security requirements as needed.

NRC Joins Five Other Agencies in Reporting on Navajo Land Contamination

Maureen Conley
Public Affairs Officer
 

navajoThe government has made good progress in reducing risks from uranium contamination on Navajo land, five federal agencies told Congress in a report last week. EPA compiled the report with input from the NRC, the Department of Energy, the Bureau of Indian Affairs, the Centers for Disease Control and the Indian Health Service.

This report recaps work done since October 2007. At that time, Congress asked the agencies to develop a five-year plan to address the contamination, which dates back to the 1940s.

Demand for uranium skyrocketed near the end of World War II. The ore was needed for nuclear weapons manufacturing and later to fuel commercial power reactors. The Navajo Nation lands had large uranium deposits, but mining and milling then was not nearly as regulated as it is today. Mining companies left extensive contamination requiring cleanup.

In 1978 Congress passed a law to ensure that uranium mill waste (called tailings) would be safely managed into the future. Under that law, DOE is responsible for the long-term care and maintenance of four former mill sites: Tuba City, Ariz.; Shiprock, N.M.; Mexican Hat, Utah; and Monument Valley, Ariz.

The NRC oversees DOE’s work at those sites. For example, DOE is responsible for cleaning up contaminated groundwater at the sites. The NRC reviews those cleanup plans. DOE monitors disposal facilities for uranium mill tailings. The NRC observes DOE inspections at the sites. The NRC also reviews and comments on DOE’s performance and environmental reports.

While the NRC does not regulate mine cleanup, the agency will also be working closely with EPA, DOE, the New Mexico Environment Department, and the Navajo Nation during the cleanup of a contaminated mine site in Church Rock, N.M. This conventional strip mine operated from 1967 to 1982. EPA plans call for the mine waste to be disposed at the nearby Church Rock mill site, which must be done in compliance with NRC disposal regulations.

Over the past five years, NRC staff has met many times with members of the Navajo Nation. We will continue these oversight and outreach activities.

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