As of October 15, 2014.......Bill 77 is now law.
If you have any gas appliances (furnace, stove etc) or a garage connected to your home, carbon monoxide detectors are MANDATORY on each level of your home. This law also applies to condos, university residences & hotels.
If you are a landlord (or have one) who hasn't addressed this issue, it's not optional. If you are a tenant, send them this link and tell them you just saved them a LOT of money.
Be aware that fire departments near you will enforce the new regulation during random home inspections for smoke detectors, which are also mandatory.
Penalties for non-compliance are the same as those for failing to have a smoke detector. Inspectors can issue $235 tickets or lay charges that could result in fines of up to $50,000 for individuals and $100,000 for companies.
Still smarter and cheaper to buy the required safety devices.