Sound Pressure Profiles in Wholesale Fruit and Vegetable Markets in Kathmandu Valley, Nepal

Abstract

Wholesale fruit and vegetable markets are busy urban workplaces where vehicles, loading activities, bargaining, horn use, and crowd movement can create continuous noise. This study assessed the environmental noise in two of the major wholesale produce markets of Kathmandu Valley, i.e. Kalimati and Balkhu, during the principal trading periods of the day. Noise levels were recorded at both markets throughout seven consecutive days using class 2 integrating sound meter. On each day, a 60-minute reading were taken during three primary trading periods: morning (05:00-07:00), midday (12:00-14:00), and evening (16:00-18:00). Noise meter was set to A-weighting and logged sound levels at 1-minute intervals where on each session, the hourly equivalent continuous sound level (LAeq,1h) and percentile levels (L10, L50, and L90) were calculated. Results were then compared with Nepal’s National Sound Quality Standard (NSQS) daytime commercial area limit of 65 dB(A). Kalimati and Balkhu’s morning noise levels were the highest and similar to each other (76 .59 and 76.63 dB(A), decrease in midday and differed considerably (67.35 and 60.14 dB(A)) and evening levels intensified in both market (71 .53 and 70.20 dB(A)) respectively. All the day, Kalimati surpassed 65dB(A) in every inspected period whereas Balkhu crossed guideline in the morning and evening but not at midday. Percentile metrics showed frequent peak events (morning L10 approximately 79-80 dB(A)) while background level (morning L90 approximately 71 72 dB(A)). Under an illustrative vendor activity pattern (3 h morning, 2 h midday, and 3 h evening), estimated LEX, 8h for Kalimati and Balkhu were 73.8 dB(A) and 73.3 dB(A) respectively. The finding support practical recommendations such as delivery management, horn control, improved loading circulation, and adaptations for small scale stalls. These measures should be presented as recommendation rather than the tested intervention.