Over 170 countries have agreed to limit global emissions from a powerful chemical used in air-conditioners and refrigerators, following a climate change summit in Kigali, Rwanda this week.

Hydrofluorocarbons—or HFCs—are chemical coolants that trap heat in the atmosphere, making them thousands of times more potent and harmful than greenhouse gases like carbon dioxide. Air-conditioners, which typically employ HFCs, have been determined as the chemical's biggest disseminators—HFCs previously replaced chlorofluorocarbons, or CFCs, which contributed to the erosion of the ozone layer.

Still, HFCs do their own damage, and the deal reached early this morning will require developed countries to reduce HFC emissions by 10 percent by 2019, and then by 85 percent by 2036. Less developed countries like China and some African nations will begin phasing out HFCs by 2024, and further developing countries like India, Pakistan, and Iran will begin the process in 2028, eventually reducing HFCs by 85 percent by 2047.

Over the last seven years, negotiators have had trouble convincing underdeveloped countries like India to reduce HFCs, since the chemical has made air-conditioning cheaper and more attainable for poorer nations. India has argued that swapping out HFCs for less harmful coolants will hurt them. "There are issues of cost, there are issues of technology, there are issues of finances," Ajay Narayan Jha of India's environment and climate change ministry said, before the deal was announced. "We would like to emphasize that any agreement will have to be flexible from all sides concerned. It can't be flexible from one side and not from the other."

Still, the deal—which is part of the 1987 Montreal Accord—has been reached at last, and though some climate activists say it's not as binding as they'd like it to be, it's at least something. "It’s not the best deal we could have got, but it’s a good deal,” Mattlan Zackhras, a negotiator from the Marshall Islands, said in a statement. "It’s a step toward ensuring the survival of our island, but we need to take further steps."