The IBC-2000 and 2003 primarily addressed critical equipment being certified to be able to withstand certain seismic design loads of a given project. Critical equipment needs to be certified through independent analysis or testing to prove the equipment will remain operational after a seismic event. The 2006 version of the code does not limit the online functionality of critical equipment to only seismic events. It implies equipment should remain operational after other natural events such as wind.

The U.S. Geological Survey (USGS) also changed some of the values of the mapped short period response spectra (Ss) throughout the country. In some areas some values went up in others they went down.

The biggest changes to the code occurred in the 2006 version where factors such as the Response Modification Factor (Rp) and Amplification Factor (ap) changed. This has caused the calculation for the seismic design force to increase dramatically for engine generator sets.

The state of California has adopted the 2006 version of the IBC code. We would also recomend to check with your local county as they may alter the code requirements to suit their needs.

The IBC has replaced regional codes in most jurisdictions and incorporates strong provisions regarding seismic and wind performance of electric generating sets that construction professionals need to understand. Generator sets are most susceptible to earthquake-related damage at the points where components – including the engine exhaust system, fuel lines, AC power-supply wring, load wiring and control wiring – interconnect. These connections must be flexible, so relative motion can be absorbed without damage. Without this flexibility, the building or generator set may be damaged and the generator may fail while in service. Additionally, when vibration isolation is required in a seismic application, seismically certified vibration isolators must be used to ensure the generator set isn’t dislodged from the building structure during the seismic event.

The International Building Code (IBC) is a set of rules for engineers working with generating equipment and supervising its installation. It addresses both the design and installation of building systems, with an emphasis on how those systems will perform in emergency situations – and continue to perform after such event.