Page 243 - Solid Waste Analysis and Minimization a Systems Approach

REQUIRED DATA TYPES 221

■ ISO 9000 registration (if yes, date received)—Collected to predict the poundage of
solid waste streams generated.
■ ISO 14000 registration (if yes, date received)—Collected to predict the poundage
of solid waste streams generated.
■ U.S. state of operation—Collected to examine the effects of varying environmental
regulations among states.

The sources from which the variables were identified are as follows:

■ Literature review (related previous studies on aggregate waste generation)
■ Survey of the industry (consulted leading U.S. waste management experts)
■ The researcher’s experience and previous research

The potential independent variables were believed to aid in the prediction of solid
waste because of their relationship to waste compositions and quantities. Many were
obvious, such as number of employees and business type, while others, like environ-
mental certifications and landfill-disposal costs, were hypothesized based on informa-
tion from the literature review.
SIC codes were used as the basis to define business functions for each company.
SIC codes were chosen as the basis to group companies to characterize solid waste
because

■ Most U.S. environmental regulators use this classification system when reporting
solid waste data.
■ SIC code classification has been used in previous waste generation studies (as indi-
cated in the literature review).
■ Broad business function–based system (99 classifications of companies)
■ Mutually exclusive classifications
■ Researched and developed by the U.S. government

14.2.1 SIC CODE GROUPINGS
The SIC system is a series of numbers, each ranging from 0 to 9, used to label indus-
tries. Primary industries use either 0 or 1, secondary industries use 1, 2, or 3, and ter-
tiary industries use numbers 4 through 9. As more digits are added to the number, the
classification becomes more specific. For example, the SIC code 8 refers to the serv-
ice industry, 82 refers to educational services, and 829903 refers to music and drama
schools (Encarta, www.encarta.msn.com, retrieved January 9, 2001).
The SIC system was a useful indicator for a given company’s solid waste genera-
tion rates and composition. The SIC codes were useful in grouping companies into
categories for this research. Following is a complete listing of all Standard Industrial
Classification (SIC) codes developed by the U.S. Department of Labor to classify
industries (U.S. Department of Labor, www.dol.gov, retrieved May 4, 2002):