The concentration of negative ions is one of the indicators of air quality. According to the World Health Organization, the standard concentration of negative oxygen ions in fresh outdoor air is 1,000~1,500 ions/cm³, while a healthy concentration indoors for urban residents ranges from 40~100 ions/cm³.
The negative oxygen ion detector is used to monitor ion concentrations in sectors such as forestry, environmental protection, meteorology, and tourism, helping to improve air quality in both rural and urban areas. High-sensitivity negative ion detectors feature fast response times and are mainly used to measure the negative ion concentration in materials such as negative ion coatings and fabrics.