Page 235 - Plant design and economics for chemical engineers

206 PUNT DESIGN AND ECONOMICS FOR CHEMICAL ENGINEERS

involved if the complete plant is to function as an efficient unit. The expendi-
tures required for routine plant services are included in plan&overhead costs.
Nonmanufacturing machinery, equipment, and buildings are necessary for many
of the general plant services, and the fixed charges and direct costs for these
items are part of the plant-overhead costs.
Expenses connected with the following comprise the bulk of the charges
for plant overhead:

Hospital and medical services
General engineering
Safety services
Cafeteria and recreation facilities
General plant maintenance and overhead
Payroll overhead including employee benefits
Control laboratories
Packaging
Plant protection
Janitor and similar services
Employment offices
Distribution of utilities
Shops
Lighting
Interplant communications and transportation
Warehouses
Shipping and receiving facilities

These charges are closely related to the costs for all labor ‘directly
connected with the production operation. The plant-overhead cost for chemical
plants is about 50 to 70 percent of the total expense for operating labor,
supervision, and maintenance.

ADMINISTRATIVE COSTS
The expenses connected with top-management or administrative activities can-
not be charged directly to manufacturing costs; however, it is necessary to
include the administrutive costs if the economic analysis is to be complete.
Salaries and wages for administrators, secretaries, accountants, stenographers,
typists, and similar workers are part of the administrative expenses, along with
costs for office supplies and equipment, outside communications, administrative
buildings, and other overhead items related with administrative activities. These
costs may vary markedly from plant to plant and depend somewhat on whether
the plant under consideration is a new one or an addition to an old plant. In the