The National Electrical Contractors Association (NECA) recently published NECA 406-2003, Standard for Installing Residential Generator Sets. The standard covers generators that are permanently installed in single-family dwellings for backup power and powered by gasoline, natural gas, or LP gas.
NECA 406 is the twenty-fourth volume of the National Electrical Installation Standards series of publications, and it’s approved by the American National Standards Institute. Copies of the standard are available for $30 by calling the NECA order desk at (301) 215-4504, or as a free PDF at www.neca-neis.org/standards.