Reference: Fataawa al-Lajnah ad-Daa.imah lil-Buhooth al-‘Ilmiyyah wal-Iftaa. – Fatwa No.13489
Fataawa Ramadhaan – Volume 1, Page 382, Fatwa No.341
Question: In our village there is a man who works in a bakery baking bread. He is a man who prays and fasts [the month of] Ramadhaan, and all Praise is due to Allaah [alone], however, he asked me whether it was permissible for him not to fast during Ramadhaan, keeping in mind that he works close to the raging fire whilst baking bread all day long whilst he is fasting. Because of this, he feels extremely thirsty and exhausted at work. So I anticipate from yourselves to favour me with a clear response regarding this, and may Allaah reward you all, in shaa.-Allaah.
Response: It is not permissible for this man not to fast [during Ramadhaan], rather it is obligatory upon him to fast. The fact that he bakes during the day in Ramadhaan is not a[n] [acceptable] reason not to fast. [So] it is upon him to work according to his ability.
And with Allaah lies all success, and may Allaah send prayers and salutations upon our Prophet Muhammad ﷺ and his family and his companions.