March 13, 2006

Sandia-developed RADTRAN software turns 30

Software analyzes risks, consequences of radiation
material transportation

ALBUQUERQUE, N.M. — RADTRAN, software developed by Sandia National Laboratories for assessing risks and consequences of transporting radioactive material, turns 30 this year.

Originally developed in-house in 1976, the software ran only on Sandia computers and was used inside Sandia between 1977 and 1986. It was made available to the public in 1986.

Today, the code has 200 users throughout the world, ranging from companies that need to transport small medical devices containing radioactive materials to those transporting spent radioactive fuel from nuclear power plants. The U.S. Department of Energy (DOE) funds the project, making it free to users around the world that transport radioactive materials.

“This software is the national and international standard for risk assessment and consequence analysis for transportation of radioactive materials,” says Ruth Weiner, a one-time RADTRAN user and now project lead of the program. “It calculates potential doses of radiation to the public and transportation workers, both in normal transportation operations and resulting from accidents.”

RADTRAN has gone through several upgrades since its inception, with RADTRAN 6.0 expected to launch this year. RADTRAN 5.5 was released in 2003 and was the first downloadable version of the software.

Sandia is a National Nuclear Security Administration laboratory.

The RADTRAN code combines user-determined demographic, routing, transportation, packaging, material, and radionuclide data with meteorological and health physics data to calculate expected radiological risks and consequences for the transportation of radioactive materials. Since its inception, it has been used in most radiological transportation environmental assessments and environmental impact statements.

Users submit an online application and, upon approval, have access to the software. They are e-mailed a user guide to assist them in the downloading process.

“RADTRAN allows users to track potential radiation releases, for example, as a truck carrying radioactive materials travels along a highway,” Weiner says. “It calculates potential doses of radiation coming from a shipment to various populations.”

She adds that RADTRAN does not make statements about shipment safety; it only does calculations.

“We don’t think we can tell members of the public or decision makers that something is safe or not safe,” she says. “We give them the data and they can decide for themselves.”

“We’ve been looking at and collecting data since 1970,” Weiner says. “There’s never been an accident where there has been a release of radioactive material that was more than the very small releases allowed by Nuclear Regulatory Commission regulations.”

Weiner says radioactive materials have been transported around the U.S. since the 1950s. About 90 percent of the millions of radioactive materials packages transported are for medical and industrial uses and are transported by commercial shipping entities. Highly radioactive materials are transported in large well-shielded casks, like those carrying spent nuclear fuel between nuclear power plants and to and from several DOE facilities. Transuranic radioactive waste is carried regularly to the Waste Isolation Pilot Plant (WIPP) in Carlsbad in TRUPACT-II containers designed by Sandia.

The United States has agreements with other countries to provide them with nuclear power plant fuel. Under the agreements, the countries must return the spent fuel, which is then transported cross-country to locations such as Idaho National Laboratory.

Since Sept. 11, 2001, RADTRAN has been used to estimate the radiological consequences of a potential deliberate attack, although there has never been such an attack.

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Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin company, for the U.S. Department of Energy’s National Nuclear Security Administration. Sandia has major R&D responsibilities in national security, energy and environmental technologies, and economic competitiveness.

Sandia media contact: Chris Burroughs,, (505) 844-0948

Sandia technical contact: Ruth Weiner,, (505) 284-8406