With the natural disasters that have become major headlines over the past few years, what happened to the emergency generators during these disasters was pushed into the light. Generators ran out of fuel, failed to start, broke down during operation, or were flooded among other issues. Other generators were unaffected or experienced minimal problems. Although there is never a guarantee that any specific generator will always function there are steps that can be taken to increase that probability. NFPA codes standards that require the installation of an emergency or legally required generator refer to NFPA 110, Emergency and Standby Power Systems for installation, testing and maintenance requirements that pertain to the performance of the system. The National Electrical Code (NEC) covers the electrical installation of any generator but NFPA 110 adds some things the affect the performance. NFPA 110 contains a commissioning test to make sure that the system functions as intended.
Testing a generator every day, week or month at 100% of its load for 100% of its designed operating time does not guarantee it will function when called upon. Such testing also may increase the wear and tear on the generator and increase the likelihood of a failure. NFPA 110 contains routine maintenance and operational testing requirements to help keep the system running when called upon. NFPA 110 is a consensus standard (as are all NFPA codes and standards) which provides routine tests that have been vetted by the public, generator manufacturers, listing organizations, and maintenance personnel from hospitals, sports arenas, and many more. The testing required 10 years ago is not the same as it is today. To benefit from the knowledge gained as a result of the disasters necessitates that the most recent edition be used for the testing of an existing system. NFPA 110 is written such that the routine tests are designed to be applied to existing generators installed under any previous edition. In fact, the routine maintenance in Chapter 8 is specifically stated as be applicable to existing systems.
One thing NFPA 110 does not do is dictate the physical location of the emergency generator, its fuel system, or any other portion of the emergency system (NFPA 110 stops at the load terminals of the transfer switch). Not all locations are subject to earthquake, snow storms or tornados. Not all basements are subject to flooding. Requiring that protection from all disasters be addressed is beyond the requirements of any code or standard. As a minimum standard NFPA 110 points out conditions that should be considered when selecting the installation site. Protection from floods, fire, vandalism, wind, earthquakes, lightning, and other environmental conditions common to the geographic location should be considered. The probability and frequency of a power failure as a result of lightning, wind, and rain produced by thunderstorms, tornadoes, and similar weather conditions should be considered. Consideration should also be given to fuel delivery problems due to weather, fuel shortages, and other geographic and environmental conditions. The location of the EPSS equipment should not be subject to flooding from natural causes or from accumulations of water due to firefighting, sprinkler operation, or a building system malfunction. The fuel storage tanks, fuel pumps, etc. are also subject to the damaging effects of floods and earthquakes. NFPA 110 can not anticipate every installation site around the world. Designers should consider the placement and protection of these to allow the EPSS to function after an incident. Different methods can be employed to provide the specifically needed protection. Those responsible for the system must consider on-site situations that could impact the performance of the system and must make the appropriate adjustments.
NFPA 110 has many requirements that increase the likelihood that an emergency generator will have enough fuel and be functional for the time it was designed to operate when the emergency need arrives. And isn't that what is important?