The effects of color preference and noticeability of trash bins on waste collection performance and waste-sorting behaviors.

The improvement of waste separation is of great interest in mitigating problems related to municipal solid waste (MSW) management. Trash bins are commonly used for waste separation at source. Thus, appropriate trash bin designs are promising to improve waste collection and separation performance. This study investigated the effect of trash bin design on waste collection and waste-sorting behaviors in Thailand, focusing on color preference, setting location, and perceived ease in finding a trash bin (noticeability). Trash bins to separately collect compostable waste, recyclable waste, and PET bottles were tested. Perceived preferences for colors and noticeability were evaluated using pairwise comparison by survey questionnaires with a sample size of 889 respondents. Waste collection experiments were conducted to reveal waste collection, capture, contamination, and effective capture rates in three locations for 15 weeks. The results were analyzed via statistical methods. They suggested that trash bins with the least preferred colors had the highest waste separation efficiencies. On the other hand, color preference towards trash bins had no significant impact on waste collection. In addition, lower color preference contributed to lower noticeability of trash bins. The effective capture rate had a significantly negative correlation with noticeability. Highlighting the location of less noticeable trash bins might have helped participants practice correct waste disposal. In conclusion, location, unit color, and noticeability of trash bins can affect waste collection and separation performance. Increasing human awareness through appropriate design and setting of trash bins might enable more efficient collection of segregated wastes.