Ramadan begins July 10. Adult Muslims are required to abstain from food and liquids from sunrise to sundown.
The National Center of Meteorology and Seismology in Abu Dhabi in the United Arab Emirates warned outdoor workers will have an especially hard time with temperatures likely to soar into triple digits, high humidity in some areas and days of 15 hours.
"Do reap the blessing of the month but be careful when working outdoors," the center said. "Ramadan this year comes in the summer period and this period of the year is characterized by high temperatures during the day."
Sulman Haider, an Indian working in the UAE, said he spends about seven hours outside during his workday.
"It will be tough especially when the body fluids are low, but I have to obey my Lord and I'll be doing it in the best possible way," he said.
Adults who are ill or disabled and women who are menstruating, pregnant or breast-feeding are exempt from the fast.
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