INSTALL A GENERATOR FOR EMERGENCY POWER 
Protecting Your Property from Natural Hazards
FEMA 
April 2008

Power outages are commonplace during disasters, and they may last 
for several days. As a result, even businesses that are not 
severely damaged can suffer losses because of the interruption of 
normal operations or the loss of perishable stock. You can reduce 
these losses and speed the recovery process by installing an 
emergency generator. First, determine which systems and equipment 
are essential to the continued operation of your business. They 
may include one or more of the following: 

* Heating, ventilation, and air conditioning (HVAC) systems 

* Industrial equipment and major appliances, such as 
refrigerators and freezers 

* Lights (interior and exterior), computers, and other office 
equipment 

* Pumps, including sump pumps, sprinkler system pumps, and well 
water pumps 

* Alarm systems 

Once you have identified the essential systems and equipment, 
determine how much power they require. Then check with a 
generator sales representative regarding the appropriate size and 
type of generator. The sales representative can also help you 
select other components of the emergency power system, including 
the main transfer switch and the electrical panel. 

[Begin illustration]
This illustration shows a diesel generator for emergency power. 
It shows a generator and fuel tank with anchor bolt securing it 
to concrete pedestals which raise the generator and fuel tank 
above flood level. It also shows that there should be adequate 
space for maintenance, and that walls of the building provide 
protection from wind and windborne debris.
[End illustration]

BENEFITS OF USING GENERATORS

* Helps to prevent the interruption of normal business operations

* Helps to prevent the loss of perishable stock

* Helps to speed the recovery process  

TIPS 

Keep these points in mind when you select and install a 
generator: 

* Protect your generator and its fuel tank from flooding and high 
winds. In flood hazard areas, mount the generator and tank 
securely on concrete platforms, above the expected flood level. 
Install the generator and tank inside or next to a building or 
protective structure to shield them from wind and windborne 
debris. Electrical and fuel supply lines must also be protected. 
And remember that your generator must be accessible for 
maintenance and that exhaust gases must be routed to the outside 
if the generator is installed in an enclosed area. 

* Some systems and equipment may have to operate continuously 
(refrigerators for example), while others may be needed only 
during normal business hours (such as office equipment). 

* You will need more power to restart systems and equipment when 
the power fails than to continue operating them after startup. 
The generator you choose must be able to meet both of these 
needs. (You can minimize the power requirements for startup by 
starting individual systems and equipment in sequence rather than 
all at once.) 

* Before you buy a generator, ask your utility company if it has 
regulations that govern the use of emergency power equipment. 
Also, the installation of the generator and all wiring, switches, 
and other electrical components must meet the requirements of 
your local electrical codes. 

* Be sure to maintain an adequate supply of fuel. Your sales 
representative should be able to tell you the generator’s rate of 
fuel consumption at various power output levels. 

* Follow the manufacturer’s recommendations for routine 
maintenance of your generator. 

ESTIMATED COST 

The cost of a generator will depend on the types and amount of 
equipment and systems that need to be powered, the requirements 
of local codes and utility companies, and the type of generator 
you choose and its specifications (i.e., amperage, voltage). 

OTHER SOURCES OF INFORMATION 

FEMA 141, Emergency Management Guide for Business and Industry, 
October 1993, 
http://www.fema.gov/library/viewRecord.do?id=1689.  

FEMA 259, Engineering Principles and Practices of Retrofitting 
Floodprone Structures, January 1995, 
http://www.fema.gov/library/viewRecord.do?id=1645.

To obtain copies of FEMA documents, call the FEMA Publications 
Warehouse at 1-800-480-2520 or visit FEMA’s Library online at 
http://www.fema.gov/library.