Montreal Protocol (1973) and the international agreement signed (1985 & 1987). The treaty is structured around several groups of halogenated hydrocarbons that deplete stratospheric ozone. All of the ozone depleting substances controlled by the Montreal Protocol contain either chlorine or bromine (substances containing only fluorine do not harm the ozone layer). Some ozone-depleting substances (ODSs) are not yet controlled by the Montreal Protocol, including nitrous oxide (N2O) For a table of ozone-depleting substances controlled by the Montreal Protocol see: For each group of ODSs, the treaty provides a timetable on which the production of those substances must be shot out and eventually
Montreal flood of 1987 Montreal Metro, buses and suburban train service were stopped. The basement of an elderly care hospital in the Saint-Henri neighbourhood was flooded and 240 patients were left without electricity, food, and health services for a while. Most home insurance claims were declined unless the insured was specifically covered by a clause concerning flood. However, the car owners were covered. The Quebec government promised monetary help but only 20 to 40% of the expected C$40 million was ever distributed. Court cases against the municipal authorities, including a class action, were rejected as the flood was considered in legal terms an "Act