Hazardous MaterialsCooking Material-Storage Containers to Assess Fire Safety

Published 7 December 2021

Researchers have completed a series of tests on specially designed stainless-steel containers used by the Department of Energy for storage and transportation of hazardous materials. Even at 2000 degrees, the sealed, stainless-steel containers did not split open.

A team at Sandia National Laboratories has completed a series of tests on specially designed stainless-steel containers used by the Department of Energy for storage and transportation of hazardous materials.

The engineers, technologists and project managers were surprised to find that the containers did not split open when heated to 2000 degrees Fahrenheit. That is almost as hot as a cement kiln.

“These containers were welded shut and heated to 2000 degrees, so we assumed that they were going to split open, but they developed small pinholes instead,” said Walt Gill, the test director and Sandia mechanical engineer. “We think the material inside reacted with the container itself and produced the pinholes in the container. These tiny holes let out all of the superheated gas without the containers pressurizing and pulling themselves apart.”

The series of 10 tests were designed to mimic a hypothetical raging-hot fire burning at a DOE facility and engulfing a container that had been knocked on its side and left outside of its insulated packaging, which protects it from heat. Since these containers are not designed to withstand such a fire, the goal of the test was to determine how much, if any, material stored within the container would be released into the air during such an accident, said Gill and Austin Baird, the test engineer.

Because the container is a complex, layered system of steel containers, hopefully any material that gets out through a pinhole would be contained or reduced by an outer layer. In 2018, the team conducted similar tests assessing the safety of similar containers.

This information will be used by policymakers to determine safety regulations to protect employees and the environment.

Nested Containers for Storage and Handling
The stainless-steel containers are nested in one another as part of a complex layered system, said Baird. There is an inner stainless-steel container with a pop-on lid like a cookie tin called a convenience can. Then there are two stainless-steel containers that are welded shut: an inner container and an outer container. These three containers are placed within another package for shipping. The containers are used throughout the DOE complex.