Research_Data2026
Description
This dataset documents indoor environmental conditions in ten educational institutions observed over an 18-month period. The institutions are organised into two groups of five. Group A institutions maintained permanent soil-based potted plants in indoor learning spaces (classrooms, corridors, reception areas, staff rooms and shared spaces), while Group B institutions kept plants outdoors only (gardens, courtyards, entrance landscaping and exterior planters). Data were collected through repeated, non-identifiable site observations and field notes recorded across six predefined observation domains: (D1) location and density of indoor plants; (D2) watering and drainage conditions; (D3) visible dampness and contamination; (D4) cleanability of surfaces; (D5) perceived breathing comfort; and (D6) absence and learning-continuity patterns. Building age, crowding, ventilation habits, cleaning routines, climate conditions and room use were recorded as potential confounders during collection. No medical examinations, lung-function tests, personal health records, microbial identification or laboratory air or bioaerosol samples were collected. The dataset is provided as a structured qualitative observation matrix in which each of the ten institutions forms one row and each of the six domains forms one column, accompanied by descriptive data notes and a graphical summary of the recorded observations. The dataset can be reused by researchers in indoor environmental quality, school and facility management, and building-health studies to support