Over at Middle Atlantic, I found this about earthquake testing:
Subject: Revised Seismic Certification of the xxx Series Rack Enclosures
At your request, yyyyyyy, Inc. has reviewed the previously completed test report
referenced above and have updated the capacities of the subject rack enclosure in accordance with
the provisions of the 2010 Edition of ASCE Standard 7 (ASCE 7-10) which is the basis for the 2009
and 2012 IBC, 2010 CBC, and the 2009 edition NFPA 5000.
So there are standards available.
