Street cleaners in Dubai are wearing new "cooling collars" to prevent heatstroke as they work in rising Gulf temperatures that can hit 45 degrees C (113 degrees F), Dubai said Wednesday. The Middle East emirate issued orange fabric collars containing a chilled gel, similar to the cold compresses used for injuries, to 4,000 cleaners. "This type of cooling material [can]… protect the body from high temperature so that the worker is not subject to heat exhaustion," Abdulmajeed Saifaie, director of the waste department, said in a statement. Projections show the Gulf region will be the world's hottest region by 2100 as a result of climate change. With small, wealthy populations and minimal domestic food production, oil-rich states in the Gulf can respond better to rising heat than poorer countries in South Asia, experts say. The collars can work for up to six hours, after which they must be put in a fridge to refreeze the gels. Temperatures in the Gulf will become "intolerable" for humans by the end of the century if climate change is not addressed, a 2015 Nature Climate Change study showed.