Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Propagation Measurements Before, During, and After the Collapse of Three Large Public Buildings



Christopher L. Holloway, Galen H. Koepke, Dennis G. Camell, William F. Young, Catherine A. Remley


NIST is investigating radio communications problems faced by emergency responders (e.g., firefighters and police) in disaster situation such as collapsed buildings. A fundamental challenge to communication into and out of large buildings is the strong attenuation of radio signals caused by losses and scattering in the building materials and structures, and the problem is amplified in a collapsed building. We are investigating various schemes for detecting emergency responders and civilians with portable radios or cell phones who may be trapped in voids in a collapsed or partially collapsed building. The first part of this effort is to understand radio propagation in collapsed structures. Buildings scheduled for implosion provide the ideal research environment for investigating radio-wave propagation issues in fully or partially collapsed structures. The experiments reported here were performed before, during, and after the implosion of three large building structures and consist of measurements of the attenuation of radio signals caused by the building materials and structures. Measurements were performed at various frequencies of interest to emergency responders, namely, frequencies near the public safety and cell phone bands (approximately 50 MHz, 150 MHz, 225 MHz, 450 MHz, 900 MHz, and 1.8 GHz).
IEEE Antennas and Propagation Magazine


building implosion, building shielding and coupling, collapsed buildings, emergency responders, radio communications, radio propagation experiments, weak-signal detection.


Holloway, C. , Koepke, G. , Camell, D. , Young, W. and Remley, C. (2014), Propagation Measurements Before, During, and After the Collapse of Three Large Public Buildings, IEEE Antennas and Propagation Magazine, [online], (Accessed June 17, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created June 1, 2014, Updated January 27, 2020