It is my understanding that we use App G for LEED energy credit analysis of
manufacturing facility (which has some offices etc.) and all the
manufacturing load counted as process load. Is this correct?

This is based on the LEED 2.2 narative in the energy credit section
(Standard 90.1 establishes minimum requirements for the energy-efficient
design of buildings, except low-rise residential buildings. The provisions
of this standard do not apply to single-family houses, multi-family
structures of three stories or fewer above grade, manufactured houses
(mobile homes) and manufactured houses (modular), or buildings that do not
use either electricity or fossil fuel).

The following bullet number 3 in the ashrae standard has me confused, but it
is not included in the LEED 2.2 narative.

2.3 The provisions of this standard do not apply to:

(a) single-family houses, multi-family structures of three stories or fewer
above grade, manufactured houses (mobile homes) and manufactured houses
(modular),

(b) buildings that do not use either electricity or fossil fuel, or

(c) equipment and portions of building systems that use energy primarily to
provide for industrial, manufacturing, or commercial processes.

Thanks

-Rohini