Reference: Fataawa Ramadhaan – Volume 2, Page 528, Fatwa No.498
Fataawa al-Lajnah ad-Daa.imah lil-Buhooth al-`Ilmiyyah wal-Iftaa. – Fatwa No.11310
Question: I inform you that I am one of the employees at the General Desalination Organisation, and the month of Ramadhaan has descended upon us and we are [all] fasting whilst at work. At the station where we work, we are exposed to water vapour which we breathe in a lot, so does this invalidate our fast? [Additionally], are we obliged to make up [the fast] for the day we breathed in the water vapour, whether [the fast was] obligatory or voluntary and is there any expiation we are required to pay for each [such] day?
Response: If the matter was as mentioned, then your fast is valid and nothing [further] is required of you.
And with Allaah lies all the success, and may Allaah send prayers and salutations upon our Prophet Muhammad (sal-Allaahu ‘alayhi wa sallam) and his family and his companions.