Here is the actual legislation Ontario Regulation 17/05, which lists the prohibited service. Smoke/Carbon Monoxide Detectors are NOT on the list:
Direct agreements subject to s. 43.1 of Act
35.1 (1) For the purpose of subsection 43.1 (1) of the Act, the following goods and services are prescribed:
2. Air conditioners.
3. Air cleaners.
4. Air purifiers.
5. Water heaters.
6. Water treatment devices.
7. Water purifiers.
8. Water filters.
9. Water softeners.
10. Duct cleaning services.
11. Any goods or services that are a combination of or that perform the functions of the goods or services listed in any of paragraphs 1 to 10. O. Reg. 487/17, s. 2.
Of course any of the prohibited items can be sold if the consumer initiated the visit.
“Before one can have a Clue they must first accumulate 10 Inklings. That said, all it takes is one bad post and you erase all Inklings & Clues accumulated'"