As of today, October 15th, 2014, Carbon Monoxide Detectors are now required in all residences in Ontario near all sleeping areas in residential homes and in the service rooms, and adjacent sleeping areas in multi-residential units. Carbon monoxide alarms can be hardwired, battery-operated or plugged into the wall.
It's important to note that while all new homes built in Half Moon Bay already have these detectors installed, but they may only be hardwired, and therefore, do not have battery back-up protection. For peace of mind it's best to invest in secondary units that have battery back-up built in.
More information about this new law can be found on the Province of Ontario website.
Learn more about Carbon Monoxide from Ottawa Fire Services.