Praise be to Allaah.
Fasting is one of the pillars of Islam which is established by the Qur’aan and Sunnah and by the consensus of the ummah. It is not permissible for the Muslim to break the fast without a legitimate shar’i excuse such as sickness or travel. A person may experience great hardship during the fast but he has to be patient and seek the help of Allaah. If a person becomes thirsty during the day in Ramadaan, there is nothing wrong with him pouring water over his head to cool himself down, or rinsing his mouth out with water. If his thirst will cause him a great deal of harm or there is the fear that he may die of thirst, then it is permissible for him to break the fast, but he has to make it up later on.
But if his work is the cause of the difficulty that he is experiencing, this is not an acceptable reason for breaking the fast, if he can take a leave of absence during Ramadaan, or he can reduce his workload during this month, or he can change his work to something that is easier.
The scholars of the Standing Committee for Issuing Fatwas said:
It is well known in Islam, and no Muslim has any excuse for not knowing, that fasting the month of Ramadaan is obligatory for every adult Muslim, and it is one of the pillars of Islam. Every adult Muslim must strive to fast this month, in obedience to the command of Allaah, in the hope of His reward and for fear of His punishment, without neglecting his worldly affairs and without letting his worldly interests affect his interests in the Hereafter. If there is a conflict between the acts of worship that have been enjoined by Allaah and his work to earn a living in this world, then he must work it out so that he will be able to take care of both. In the example mentioned in the question, he can make the night his time for doing his work to earn his living, and if that is not possible then he should take a leave of absence from his work during the month of Ramadaan, even if that is without pay. If that is not possible, then he should look for another job where he can combine the two duties and his worldly duties will not affect his duties towards the Hereafter. There are many kinds of work and the ways of earning money are not limited to this kind of difficult work. The Muslim will never be without permissible ways of earning a living which will also allow him to fulfil the duties and acts of worship that Allaah has enjoined upon him, in sha Allaah.
“And whosoever fears Allaah and keeps his duty to Him, He will make a way for him to get out (from every difficulty).
3. And He will provide him from (sources) he never could imagine. And whosoever puts his trust in Allaah, then He will suffice him. Verily, Allaah will accomplish his purpose. Indeed Allaah has set a measure for all things”
[al-Talaaq 65:2-3]
If we assume that he cannot find any work other than that which has been mentioned, which is causing such hardship and the fear that the work regulations may be so strict that he cannot practise his religion fully or perform some of its duties, then he should flee for the sake of his religion from that land to a land where he will be able to fulfil his religious and worldly duties, and co-operate with other Muslims in righteousness and piety. The earth of Allaah is spacious. Allaah says (interpretation of the meaning):
“He who emigrates (from his home) in the Cause of Allaah, will find on earth many dwelling places and plenty to live by”
[al-Nisa’ 4:100]
“Say (O Muhammad): ‘O My slaves who believe (in the Oneness of Allaah Islamic Monotheism), be afraid of your Lord (Allaah) and keep your duty to Him. Good is (the reward) for those who do good in this world, and Allaah’s earth is spacious (so if you cannot worship Allaah at a place, then go to another)! Only those who are patient shall receive their reward in full, without reckoning’”
[al-Zumar 39:10]
If none of these options are possible and he is forced to do the kind of hard work that is mentioned in the question, then he should fast until he starts feeling that he is no longer coping, then he should take just enough food and drink to keep him going , then he should refrain from eating and drinking, and he has to make it up during the days when it is easy for him to fast. End quote.
Fataawa al-Lajnah al-Daa’imah li’l-Buhooth al-‘Ilmiyyah wa’l-Ifta, 10/234-236.
They were also asked about a man who works in a bakery and he gets very thirsty and sweats at work. Is it permissible for him to break the fast?
They replied:
It is not permissible for him to break the fast; rather he must fast. The fact that he is baking during the day in Ramadaan is not an excuse for him to break the fast. He has to work according to what he is able to do. End quote.
Fataawa al-Lajnah al-Daa’imah li’l-Buhooth al-‘Ilmiyyah wa’l-Ifta, 10/238.
And Allaah knows best.
May Allah give them patience and forgive them if they can not fast 
