In my considered judgment, there is a significant error on Page 295 of the
Seismological Research Letters, May/June 1999, published by the Seismological
Society of America. This error pertains to the identification of the seismic
hazards maps used in FEMA 273, "NEHRP Guidelines for the Seismic
Rehabilitation of Buildings."
On page 295 of this publication in the first sentence in the right hand
column is the following wording: "The seismic maps that accompany the
Guidelines are available at http:geohazards.cr.usgs/gov/eq/"
The seismic maps at this web site are the USGS Seismic Hazard Maps and NOT
the maps that are to be used with the 1997 NEHRP, FEMA 273 and 310
provisions which are provided in a "Seismic Map Package" that accompany these
three seismic codes and Guidelines.
This serious misinformation helps perpetuate a growing misunderstand that
could have serious consequences because the ground motion information
presented on the USGS Seismic Hazard Maps is different than the ground motion
information presented on the paper format seismic hazard maps in the "Seismic
Since the article discusses the role of the Degenkolb firm in the ASCE/FEMA
273 Project, if this firm reviews and believes I am correct, then it is my
considered opinion that it is the Degenkolb firm's responsibility or the
responsibility of whomever prepared this article, to correct this wording
using whatever national forum and format that is appropriate as soon as
possible because of the potential legal liability for this misinformation and
I believe it is not sufficient just to notify the editor of the
Seismological Research Letters because these letters are only published every
two months and engineers could be using this misinformation right now.
For a more complete and excellent explanation of the difference in these
USGS and 1997 NEHRP, FEMA 273 and 310 seismic hazard maps read E. V.
Leyendecker's January 12, 1999, SEAINT List Server email message "Seismic
Zones in Texas - Some USGS Comments" , which should be in the SEAINT
If you have any questions, please contact Jon Heintz, Project Engineer, for
the Degenkolb managed "ASCE/FEMA 273 Project" at his email address
jheintz(--nospam--at)degenkolb.com. However, you should read E. V. Leyendecker's SEAINT
email posting first before contacting him.
I guess someone has to pick out the fly specks out of the pepper. This error
is a pretty big fly speck.
Frank E. McClure FEMCCLURE(--nospam--at)aol.com June 3, 1999, My Birthday.