Database of Iran's regions with natural air negative ions propertise based on salt:

Includes areas:

-Alborz Province

-Isfahan province

- East Azerbaijan Province

- West Azerbaijan province

- Bushehr province

- Chaharmahal and Bakhtiari province

- Khuzestan province

- Semnan

- Fars province

- Qom province

- Kerman province

- Markazi Province

- Hormozgan Province

- Iranian islands