... :1. Produce reactive oxygen: Anion can effectively activate the oxygen molecules in the air , making it more active and ... smoke , formaldehyde , benzene , ammonia , TVOC, and other harmful air chemicals , environmental health visible .7. Eliminate smoke and dust: ... warehouses, hospitals, nursery , nurseries , any indoor place of fresh air can be applied .Negative oxygen ions generated test: >3,000,000 ...