Toshihiko Matsuto*, Nobutoshi Tanaka* and Takayuki Matsuo*

*Sanitary and Environmental Engineering, Hokkaido University

+ Correspondence should be addressed to Toshihiko Matsuto:
(North 13 West 8, Kita-ku, Sapporo 060 Japan)

Abstract

Three households kept records of their daily waste generation for nine years in Sapporo. The waste was separated into five categories: food waste, trash, plastics, metal, and glass. Recycled material, such as newspaper, was not weighed. Monthly generation was shown by a median, not by an arithmetic mean because daily generation does not always follow normal distribution, and/or because quite large generation amounts are sometimes produced. Waste generation change by year was closely related to three factors: the use of disposable diapers, the number of family members, and the age of the children. Generation change by month and by week were also both discussed.

Key words: household waste, daily generation, weighing survey, long-term survey