The School Nutrition Foundation conducted a study to develop environmental and cost profiles for the production, use, and end-of-life management of disposable and reusable ware used in school cafeterias. Factors that influence purchases, along with the burdens and costs associated with the use of disposable and reusable ware in schools were studied. Data analysis was conducted using a life cycle inventory examining a sequence of steps from raw materials to final disposition.
Operational data on serving ware was collected from seven schools in Alabama and Missouri. These included three elementary schools, two middle schools, and two high schools. School staff completed surveys to record data related to weights, material types, and costs of disposable and reusable wares; quantities and costs of dishwasher chemicals; labor costs for cafeteria operations; waste disposal and recyclable pickup costs; and, utility costs for water, gas, and electricity.
A life cycle inventory examines the sequence of steps in the live cycle of a product system, beginning with raw material extraction and continuing on through material production, product fabrication, use, reuse or recycling where applicable, and final disposition.
Based on the serving ware systems studied, reusable compartment trays had a lower environmental impact and were less expensive when compared to disposable serving ware options. Reusable compartment trays used the least amount of energy, had the lowest amount of solid waste, the lowest greenhouse gas emissions, and were also the least expensive.
The type of dishwasher used had a significant impact on the environmental factors studied. Newer model dishwashers which used less water and energy reduced water usage and energy by nearly half.
For more information:
Warewash Study Summary (pdf)