The owner or operator of a stationary internal combustion engine that is used as an emergency generator and that allows for manual adjustment of the air-to-fuel ratio or ignition timing in order to affect the combustion process, shall:

1. (a) Set and maintain the ignition timing of the engine 4 degrees retarded relative to standard timing, provided that the ignition timing shall not be retarded beyond the point that:

   1. (1) The CO emission concentration increases beyond 100 ppmv;
   2. (2) The turbocharger speed is increased beyond the maximum operating speed recommended by the manufacturer;
   3. (3) The exhaust port temperature increases beyond the manufacturer's recommended maximum operating temperature; or
   4. (4) The opacity of the emissions from the engine exhaust is equal to or greater than 20% opacity;
2. (b) Install, operate, and maintain an elapsed time meter for each engine to indicate, in cumulative hours, the elapsed engine operating time for the previous 12 months;
3. (c) Determine the hours of operation for each engine for the previous 12-month period on a monthly basis; and
4. (d) Maintain records to certify that the ignition timing of the engine has been inspected and adjusted at least once every 3 years.

Source. (See Revision Note at chapter heading for Env-A 1300) #9803, eff 10-31-10; ss by #12584, eff 8-15-18